glBitmap/glBitmap.pas

{***********************************************************
glBitmap by Steffen Xonna aka Lossy eX (2003-2008)
http://www.opengl24.de/index.php?cat=header&file=glbitmap

modified by Delphi OpenGL Community (http://delphigl.com/) (2013)

------------------------------------------------------------
The contents of this file are used with permission, subject to
the Mozilla Public License Version 1.1 (the "License"); you may
not use this file except in compliance with the License. You may
obtain a copy of the License at
http://www.mozilla.org/MPL/MPL-1.1.html
------------------------------------------------------------
Version 3.0.0 unstable
------------------------------------------------------------
History
20-11-2013
- refactoring of the complete library
21-03-2010
- The define GLB_DELPHI dosn't check versions anymore. If you say you are using delphi
  then it's your problem if that isn't true. This prevents the unit for incompatibility
  with newer versions of Delphi.
- Problems with D2009+ resolved (Thanks noeska and all i forgot)
- GetPixel isn't set if you are loading textures inside the constructor (Thanks Wilson)
10-08-2008
- AddAlphaFromglBitmap used the custom pointer instead the imagedatapointer (Thanks Wilson)
- Additional Datapointer for functioninterface now has the name CustomData  
24-07-2008
- AssigneAlphaToBitmap overwrites his own palette (Thanks Wilson)
- If you load an texture from an file the property Filename will be set to the name of the file
- Three new properties to attach custom data to the Texture objects
  - CustomName  (free for use string)
  - CustomNameW (free for use widestring)
  - CustomDataPointer (free for use pointer to attach other objects or complex structures)
27-05-2008
- RLE TGAs loaded much faster
26-05-2008
- fixed some problem with reading RLE TGAs.
21-05-2008
- function clone now only copys data if it's assigned and now it also copies the ID
- it seems that lazarus dont like comments in comments.
01-05-2008
- It's possible to set the id of the texture
- define GLB_NO_NATIVE_GL deactivated by default
27-04-2008
- Now supports the following libraries
  - SDL and SDL_image
  - libPNG
  - libJPEG
- Linux compatibillity via free pascal compatibility (delphi sources optional)
- BMPs now loaded manuel
- Large restructuring
- Property DataPtr now has the name Data
- Functions are more flexible between RGB(A) and BGR(A). RGB can be saved as Bitmap and will be saved as BGR
- Unused Depth removed
- Function FreeData to freeing image data added 
24-10-2007
- ImageID flag of TGAs was ignored. (Thanks Zwoetzen)
15-11-2006
- Function SetBorderColor implemented (only used by opengl if wrap is set to GL_CLAMP_TO_BORDER)
- Function AddAlphaFromValue implemented to use an fixed Value as Alphachannel
- Function ReadOpenGLExtension is now only intern
29-06-2006
- pngimage now disabled by default like all other versions.
26-06-2006
- Setting up an anisotropic filter of 0 isnt allowed by nvidia (Thanks Ogridi)
22-06-2006
- Fixed some Problem with Delphi 5
- Now uses the newest version of pngimage. Makes saving pngs much easier.
22-03-2006
- Property IsCompressed and Size removed. Not really supported by Spec (Thanks Ogridi)
09-03-2006
- Internal Format ifDepth8 added
- function GrabScreen now supports all uncompressed formats
31-01-2006
- AddAlphaFromglBitmap implemented
29-12-2005
- LoadFromResource and LoadFromResourceId now needs an Instance and an ResourceType (for ID)
28-12-2005
- Width, Height and Depth internal changed to TglBitmapPixelPosition.
  property Width, Height, Depth are still existing and new property Dimension are avail
11-12-2005
- Added native OpenGL Support. Breaking the dglOpenGL "barrier".
19-10-2005
- Added function GrabScreen to class TglBitmap2D
18-10-2005
- Added support to Save images
- Added function Clone to Clone Instance
11-10-2005
- Functions now works with Cardinals for each channel. Up to 32 Bits per channel.
  Usefull for Future
- Several speed optimizations
09-10-2005
- Internal structure change. Loading of TGA, PNG and DDS improved.
  Data, format and size will now set directly with SetDataPtr.
- AddFunc now works with all Types of Images and Formats
- Some Funtions moved to Baseclass TglBitmap
06-10-2005
- Added Support to decompress DXT3 and DXT5 compressed Images.
- Added Mapping to convert data from one format into an other.
05-10-2005
- Added method ConvertTo in Class TglBitmap2D. Method allows to convert every
  supported Input format (supported by GetPixel) into any uncompresed Format
- Added Support to decompress DXT1 compressed Images.
- SwapColors replaced by ConvertTo
04-10-2005
- Added Support for compressed DDSs
- Added new internal formats (DXT1, DXT3, DXT5)
29-09-2005
- Parameter Components renamed to InternalFormat
23-09-2005
- Some AllocMem replaced with GetMem (little speed change)
- better exception handling. Better protection from memory leaks.
22-09-2005
- Added support for Direct Draw Surfaces (.DDS) (uncompressed images only)
- Added new internal formats (RGB8, RGBA8, RGBA4, RGB5A1, RGB10A2, R5G6B5)
07-09-2005
- Added support for Grayscale textures
- Added internal formats (Alpha, Luminance, LuminanceAlpha, BGR8, BGRA8)
10-07-2005
- Added support for GL_VERSION_2_0
- Added support for GL_EXT_texture_filter_anisotropic
04-07-2005
- Function FillWithColor fills the Image with one Color
- Function LoadNormalMap added
30-06-2005
- ToNormalMap allows to Create an NormalMap from the Alphachannel
- ToNormalMap now supports Sobel (nmSobel) function.
29-06-2005
- support for RLE Compressed RGB TGAs added
28-06-2005
- Class TglBitmapNormalMap added to support Normalmap generation
- Added function ToNormalMap in class TglBitmap2D to genereate normal maps from textures.
  3 Filters are supported. (4 Samples, 3x3 and 5x5)
16-06-2005
- Method LoadCubeMapClass removed
- LoadCubeMap returnvalue is now the Texture paramter. Such as LoadTextures
- virtual abstract method GenTexture in class TglBitmap now is protected
12-06-2005
- now support DescriptionFlag in LoadTga. Allows vertical flipped images to be loaded as normal
10-06-2005
- little enhancement for IsPowerOfTwo
- TglBitmap1D.GenTexture now tests NPOT Textures
06-06-2005
- some little name changes. All properties or function with Texture in name are
  now without texture in name. We have allways texture so we dosn't name it.
03-06-2005
- GenTexture now tests if texture is NPOT and NPOT-Texture are supported or
  TextureTarget is GL_TEXTURE_RECTANGLE. Else it raised an exception.
02-06-2005
- added support for GL_ARB_texture_rectangle, GL_EXT_texture_rectangle and GL_NV_texture_rectangle
25-04-2005
- Function Unbind added
- call of SetFilter or SetTextureWrap if TextureID exists results in setting properties to opengl texture.
21-04-2005
- class TglBitmapCubeMap added (allows to Create Cubemaps)
29-03-2005
- Added Support for PNG Images. (http://pngdelphi.sourceforge.net/)
  To Enable png's use the define pngimage
22-03-2005
- New Functioninterface added
- Function GetPixel added
27-11-2004
- Property BuildMipMaps renamed to MipMap
21-11-2004
- property Name removed.
- BuildMipMaps is now a set of 3 values. None, GluBuildMipmaps and SGIS_generate_mipmap
22-05-2004
- property name added. Only used in glForms!
26-11-2003
- property FreeDataAfterGenTexture is now available as default (default = true)
- BuildMipmaps now implemented in TglBitmap1D (i've forgotten it)
- function MoveMemory replaced with function Move (little speed change)
- several calculations stored in variables (little speed change)
29-09-2003
- property BuildMipsMaps added (default = true)
  if BuildMipMaps isn't set GenTextures uses glTexImage[12]D else it use gluBuild[12]dMipmaps
- property FreeDataAfterGenTexture added (default = true)
  if FreeDataAfterGenTexture is set the texturedata were deleted after the texture was generated.
- parameter DisableOtherTextureUnits of Bind removed
- parameter FreeDataAfterGeneration of GenTextures removed
12-09-2003
- TglBitmap dosn't delete data if class was destroyed (fixed)
09-09-2003
- Bind now enables TextureUnits (by params)
- GenTextures can leave data (by param)
- LoadTextures now optimal
03-09-2003
- Performance optimization in AddFunc
- procedure Bind moved to subclasses
- Added new Class TglBitmap1D to support real OpenGL 1D Textures
19-08-2003
- Texturefilter and texturewrap now also as defaults
  Minfilter = GL_LINEAR_MIPMAP_LINEAR
  Magfilter = GL_LINEAR
  Wrap(str) = GL_CLAMP_TO_EDGE
- Added new format tfCompressed to create a compressed texture.
- propertys IsCompressed, TextureSize and IsResident added
  IsCompressed and TextureSize only contains data from level 0
18-08-2003
- Added function AddFunc to add PerPixelEffects to Image
- LoadFromFunc now based on AddFunc
- Invert now based on AddFunc
- SwapColors now based on AddFunc
16-08-2003
- Added function FlipHorz
15-08-2003
- Added function LaodFromFunc to create images with function
- Added function FlipVert
- Added internal format RGB(A) if GL_EXT_bgra or OpenGL 1.2 isn't supported
29-07-2003
- Added Alphafunctions to calculate alpha per function
- Added Alpha from ColorKey using alphafunctions
28-07-2003
- First full functionally Version of glBitmap
- Support for 24Bit and 32Bit TGA Pictures added
25-07-2003
- begin of programming
***********************************************************}
unit glBitmap;

// Please uncomment the defines below to configure the glBitmap to your preferences.
// If you have configured the unit you can uncomment the warning above.
{$MESSAGE warn 'Hey. I''m the glBitmap.pas and i need to be configured. My master tell me your preferences! ;)'}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Preferences ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// activate to enable build-in OpenGL support with statically linked methods
// use dglOpenGL.pas if not enabled
{.$DEFINE GLB_NATIVE_OGL_STATIC}

// activate to enable build-in OpenGL support with dynamically linked methods
// use dglOpenGL.pas if not enabled
{.$DEFINE GLB_NATIVE_OGL_DYNAMIC}


// activate to enable the support for SDL_surfaces
{.$DEFINE GLB_SDL}

// activate  to enable the support for TBitmap from Delphi (not lazarus)
{.$DEFINE GLB_DELPHI}

// activate to enable the support for TLazIntfImage from Lazarus
{$DEFINE GLB_LAZARUS}



// activate to enable the support of SDL_image to load files. (READ ONLY)
// If you enable SDL_image all other libraries will be ignored!
{.$DEFINE GLB_SDL_IMAGE}



// activate to enable Lazarus TPortableNetworkGraphic support
// if you enable this pngImage and libPNG will be ignored
{$DEFINE GLB_LAZ_PNG}

// activate to enable png support with the unit pngimage -> http://pngdelphi.sourceforge.net/
// if you enable pngimage the libPNG will be ignored
{.$DEFINE GLB_PNGIMAGE}

// activate to use the libPNG -> http://www.libpng.org/
// You will need an aditional header -> http://www.opengl24.de/index.php?cat=header&file=libpng
{.$DEFINE GLB_LIB_PNG}



// activate to enable Lazarus TJPEGImage support
// if you enable this delphi jpegs and libJPEG will be ignored
{$DEFINE GLB_LAZ_JPEG}

// if you enable delphi jpegs the libJPEG will be ignored
{.$DEFINE GLB_DELPHI_JPEG}

// activate to use the libJPEG -> http://www.ijg.org/
// You will need an aditional header -> http://www.opengl24.de/index.php?cat=header&file=libjpeg
{.$DEFINE GLB_LIB_JPEG}


//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// PRIVATE: do not change anything! //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Delphi Versions
{$IFDEF fpc}
  {$MODE Delphi}

  {$IFDEF CPUI386}
    {$DEFINE CPU386}
    {$ASMMODE INTEL}
  {$ENDIF}

  {$IFNDEF WINDOWS}
    {$linklib c}
  {$ENDIF}
{$ENDIF}

// Operation System
{$IF DEFINED(WIN32) or DEFINED(WIN64) or DEFINED(WINDOWS)}
  {$DEFINE GLB_WIN}
{$ELSEIF DEFINED(LINUX)}
  {$DEFINE GLB_LINUX}
{$IFEND}

// native OpenGL Support
{$IF DEFINED(GLB_NATIVE_OGL_STATIC) OR DEFINED(GLB_NATIVE_OGL_DYNAMIC)}
  {$DEFINE GLB_NATIVE_OGL}
{$IFEND}

// checking define combinations
//SDL Image
{$IFDEF GLB_SDL_IMAGE}
  {$IFNDEF GLB_SDL}
    {$MESSAGE warn 'SDL_image won''t work without SDL. SDL will be activated.'}
    {$DEFINE GLB_SDL}
  {$ENDIF}

  {$IFDEF GLB_LAZ_PNG}
    {$MESSAGE warn 'The Lazarus TPortableNetworkGraphics will be ignored because you are using SDL_image.'}
    {$undef GLB_LAZ_PNG}
  {$ENDIF}

  {$IFDEF GLB_PNGIMAGE}
    {$MESSAGE warn 'The unit pngimage will be ignored because you are using SDL_image.'}
    {$undef GLB_PNGIMAGE}
  {$ENDIF}

  {$IFDEF GLB_LAZ_JPEG}
    {$MESSAGE warn 'The Lazarus TJPEGImage will be ignored because you are using SDL_image.'}
    {$undef GLB_LAZ_JPEG}
  {$ENDIF}

  {$IFDEF GLB_DELPHI_JPEG}
    {$MESSAGE warn 'The unit JPEG will be ignored because you are using SDL_image.'}
    {$undef GLB_DELPHI_JPEG}
  {$ENDIF}

  {$IFDEF GLB_LIB_PNG}
    {$MESSAGE warn 'The library libPNG will be ignored because you are using SDL_image.'}
    {$undef GLB_LIB_PNG}
  {$ENDIF}

  {$IFDEF GLB_LIB_JPEG}
    {$MESSAGE warn 'The library libJPEG will be ignored because you are using SDL_image.'}
    {$undef GLB_LIB_JPEG}
  {$ENDIF}

  {$DEFINE GLB_SUPPORT_PNG_READ}
  {$DEFINE GLB_SUPPORT_JPEG_READ}
{$ENDIF}

// Lazarus TPortableNetworkGraphic
{$IFDEF GLB_LAZ_PNG}
  {$IFNDEF GLB_LAZARUS}
    {$MESSAGE warn 'Lazarus TPortableNetworkGraphic won''t work without Lazarus. Lazarus will be activated.'}
    {$DEFINE GLB_LAZARUS}
  {$ENDIF}

  {$IFDEF GLB_PNGIMAGE}
    {$MESSAGE warn 'The pngimage will be ignored if you are using Lazarus TPortableNetworkGraphic.'}
    {$undef GLB_PNGIMAGE}
  {$ENDIF}

  {$IFDEF GLB_LIB_PNG}
    {$MESSAGE warn 'The library libPNG will be ignored if you are using Lazarus TPortableNetworkGraphic.'}
    {$undef GLB_LIB_PNG}
  {$ENDIF}

  {$DEFINE GLB_SUPPORT_PNG_READ}
  {$DEFINE GLB_SUPPORT_PNG_WRITE}
{$ENDIF}

// PNG Image
{$IFDEF GLB_PNGIMAGE}
  {$IFDEF GLB_LIB_PNG}
    {$MESSAGE warn 'The library libPNG will be ignored if you are using pngimage.'}
    {$undef GLB_LIB_PNG}
  {$ENDIF}

  {$DEFINE GLB_SUPPORT_PNG_READ}
  {$DEFINE GLB_SUPPORT_PNG_WRITE}
{$ENDIF}

// libPNG
{$IFDEF GLB_LIB_PNG}
  {$DEFINE GLB_SUPPORT_PNG_READ}
  {$DEFINE GLB_SUPPORT_PNG_WRITE}
{$ENDIF}

// Lazarus TJPEGImage
{$IFDEF GLB_LAZ_JPEG}
  {$IFNDEF GLB_LAZARUS}
    {$MESSAGE warn 'Lazarus TJPEGImage won''t work without Lazarus. Lazarus will be activated.'}
    {$DEFINE GLB_LAZARUS}
  {$ENDIF}

  {$IFDEF GLB_DELPHI_JPEG}
    {$MESSAGE warn 'The Delphi JPEGImage will be ignored if you are using the Lazarus TJPEGImage.'}
    {$undef GLB_DELPHI_JPEG}
  {$ENDIF}

  {$IFDEF GLB_LIB_JPEG}
    {$MESSAGE warn 'The library libJPEG will be ignored if you are using the Lazarus TJPEGImage.'}
    {$undef GLB_LIB_JPEG}
  {$ENDIF}

  {$DEFINE GLB_SUPPORT_JPEG_READ}
  {$DEFINE GLB_SUPPORT_JPEG_WRITE}
{$ENDIF}

// JPEG Image
{$IFDEF GLB_DELPHI_JPEG}
  {$IFDEF GLB_LIB_JPEG}
    {$MESSAGE warn 'The library libJPEG will be ignored if you are using the unit JPEG.'}
    {$undef GLB_LIB_JPEG}
  {$ENDIF}

  {$DEFINE GLB_SUPPORT_JPEG_READ}
  {$DEFINE GLB_SUPPORT_JPEG_WRITE}
{$ENDIF}

// libJPEG
{$IFDEF GLB_LIB_JPEG}
  {$DEFINE GLB_SUPPORT_JPEG_READ}
  {$DEFINE GLB_SUPPORT_JPEG_WRITE}
{$ENDIF}

// native OpenGL
{$IF DEFINED(GLB_NATIVE_OGL_STATIC) AND DEFINED(GLB_NATIVE_OGL_DYNAMIC)}
  {$MESSAGE warn 'GLB_NATIVE_OGL_STATIC will be ignored because you enabled GLB_NATIVE_OGL_DYNAMIC'}
{$IFEND}

// general options
{$EXTENDEDSYNTAX ON}
{$LONGSTRINGS ON}
{$ALIGN ON}
{$IFNDEF FPC}
  {$OPTIMIZATION ON}
{$ENDIF}

interface

uses
  {$IFNDEF GLB_NATIVE_OGL}      dglOpenGL,                          {$ENDIF}
  {$IF DEFINED(GLB_WIN) AND
       DEFINED(GLB_NATIVE_OGL)} windows,                            {$IFEND}

  {$IFDEF GLB_SDL}              SDL,                                {$ENDIF}
  {$IFDEF GLB_LAZARUS}          IntfGraphics, GraphType, Graphics,  {$ENDIF}
  {$IFDEF GLB_DELPHI}           Dialogs, Graphics,                  {$ENDIF}

  {$IFDEF GLB_SDL_IMAGE}        SDL_image,                          {$ENDIF}
  {$IFDEF GLB_PNGIMAGE}         pngimage,                           {$ENDIF}
  {$IFDEF GLB_LIB_PNG}          libPNG,                             {$ENDIF}
  {$IFDEF GLB_DELPHI_JPEG}      JPEG,                               {$ENDIF}
  {$IFDEF GLB_LIB_JPEG}         libJPEG,                            {$ENDIF}

  Classes, SysUtils;

{$IFDEF GLB_NATIVE_OGL}
const
  GL_TRUE   = 1;
  GL_FALSE  = 0;

  GL_ZERO = 0;
  GL_ONE  = 1;

  GL_VERSION    = $1F02;
  GL_EXTENSIONS = $1F03;

  GL_TEXTURE_1D         = $0DE0;
  GL_TEXTURE_2D         = $0DE1;
  GL_TEXTURE_RECTANGLE  = $84F5;

  GL_NORMAL_MAP                   = $8511;
  GL_TEXTURE_CUBE_MAP             = $8513;
  GL_REFLECTION_MAP               = $8512;
  GL_TEXTURE_CUBE_MAP_POSITIVE_X  = $8515;
  GL_TEXTURE_CUBE_MAP_NEGATIVE_X  = $8516;
  GL_TEXTURE_CUBE_MAP_POSITIVE_Y  = $8517;
  GL_TEXTURE_CUBE_MAP_NEGATIVE_Y  = $8518;
  GL_TEXTURE_CUBE_MAP_POSITIVE_Z  = $8519;
  GL_TEXTURE_CUBE_MAP_NEGATIVE_Z  = $851A;

  GL_TEXTURE_WIDTH            = $1000;
  GL_TEXTURE_HEIGHT           = $1001;
  GL_TEXTURE_INTERNAL_FORMAT  = $1003;
  GL_TEXTURE_SWIZZLE_RGBA     = $8E46;

  GL_S = $2000;
  GL_T = $2001;
  GL_R = $2002;
  GL_Q = $2003;

  GL_TEXTURE_GEN_S = $0C60;
  GL_TEXTURE_GEN_T = $0C61;
  GL_TEXTURE_GEN_R = $0C62;
  GL_TEXTURE_GEN_Q = $0C63;

  GL_RED    = $1903;
  GL_GREEN  = $1904;
  GL_BLUE   = $1905;

  GL_ALPHA    = $1906;
  GL_ALPHA4   = $803B;
  GL_ALPHA8   = $803C;
  GL_ALPHA12  = $803D;
  GL_ALPHA16  = $803E;

  GL_LUMINANCE    = $1909;
  GL_LUMINANCE4   = $803F;
  GL_LUMINANCE8   = $8040;
  GL_LUMINANCE12  = $8041;
  GL_LUMINANCE16  = $8042;

  GL_LUMINANCE_ALPHA      = $190A;
  GL_LUMINANCE4_ALPHA4    = $8043;
  GL_LUMINANCE6_ALPHA2    = $8044;
  GL_LUMINANCE8_ALPHA8    = $8045;
  GL_LUMINANCE12_ALPHA4   = $8046;
  GL_LUMINANCE12_ALPHA12  = $8047;
  GL_LUMINANCE16_ALPHA16  = $8048;

  GL_RGB      = $1907;
  GL_BGR      = $80E0;
  GL_R3_G3_B2 = $2A10;
  GL_RGB4     = $804F;
  GL_RGB5     = $8050;
  GL_RGB565   = $8D62;
  GL_RGB8     = $8051;
  GL_RGB10    = $8052;
  GL_RGB12    = $8053;
  GL_RGB16    = $8054;

  GL_RGBA     = $1908;
  GL_BGRA     = $80E1;
  GL_RGBA2    = $8055;
  GL_RGBA4    = $8056;
  GL_RGB5_A1  = $8057;
  GL_RGBA8    = $8058;
  GL_RGB10_A2 = $8059;
  GL_RGBA12   = $805A;
  GL_RGBA16   = $805B;

  GL_DEPTH_COMPONENT    = $1902;
  GL_DEPTH_COMPONENT16  = $81A5;
  GL_DEPTH_COMPONENT24  = $81A6;
  GL_DEPTH_COMPONENT32  = $81A7;

  GL_COMPRESSED_RGB                 = $84ED;
  GL_COMPRESSED_RGBA                = $84EE;
  GL_COMPRESSED_RGB_S3TC_DXT1_EXT   = $83F0;
  GL_COMPRESSED_RGBA_S3TC_DXT1_EXT  = $83F1;
  GL_COMPRESSED_RGBA_S3TC_DXT3_EXT  = $83F2;
  GL_COMPRESSED_RGBA_S3TC_DXT5_EXT  = $83F3;

  GL_UNSIGNED_BYTE            = $1401;
  GL_UNSIGNED_BYTE_3_3_2      = $8032;
  GL_UNSIGNED_BYTE_2_3_3_REV  = $8362;

  GL_UNSIGNED_SHORT             = $1403;
  GL_UNSIGNED_SHORT_5_6_5       = $8363;
  GL_UNSIGNED_SHORT_4_4_4_4     = $8033;
  GL_UNSIGNED_SHORT_5_5_5_1     = $8034;
  GL_UNSIGNED_SHORT_5_6_5_REV   = $8364;
  GL_UNSIGNED_SHORT_4_4_4_4_REV = $8365;
  GL_UNSIGNED_SHORT_1_5_5_5_REV = $8366;

  GL_UNSIGNED_INT                 = $1405;
  GL_UNSIGNED_INT_8_8_8_8         = $8035;
  GL_UNSIGNED_INT_10_10_10_2      = $8036;
  GL_UNSIGNED_INT_8_8_8_8_REV     = $8367;
  GL_UNSIGNED_INT_2_10_10_10_REV  = $8368;

  { Texture Filter }
  GL_TEXTURE_MAG_FILTER     = $2800;
  GL_TEXTURE_MIN_FILTER     = $2801;
  GL_NEAREST                = $2600;
  GL_NEAREST_MIPMAP_NEAREST = $2700;
  GL_NEAREST_MIPMAP_LINEAR  = $2702;
  GL_LINEAR                 = $2601;
  GL_LINEAR_MIPMAP_NEAREST  = $2701;
  GL_LINEAR_MIPMAP_LINEAR   = $2703;

  { Texture Wrap }
  GL_TEXTURE_WRAP_S   = $2802;
  GL_TEXTURE_WRAP_T   = $2803;
  GL_TEXTURE_WRAP_R   = $8072;
  GL_CLAMP            = $2900;
  GL_REPEAT           = $2901;
  GL_CLAMP_TO_EDGE    = $812F;
  GL_CLAMP_TO_BORDER  = $812D;
  GL_MIRRORED_REPEAT  = $8370;

  { Other }
  GL_GENERATE_MIPMAP      = $8191;
  GL_TEXTURE_BORDER_COLOR = $1004;
  GL_MAX_TEXTURE_SIZE     = $0D33;
  GL_PACK_ALIGNMENT       = $0D05;
  GL_UNPACK_ALIGNMENT     = $0CF5;

  GL_TEXTURE_MAX_ANISOTROPY_EXT     = $84FE;
  GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT = $84FF;
  GL_MAX_CUBE_MAP_TEXTURE_SIZE      = $851C;
  GL_TEXTURE_GEN_MODE               = $2500;

{$IF DEFINED(GLB_WIN)}
  libglu    = 'glu32.dll';
  libopengl = 'opengl32.dll';
{$ELSEIF DEFINED(GLB_LINUX)}
  libglu    = 'libGLU.so.1';
  libopengl = 'libGL.so.1';
{$IFEND}

type
  GLboolean = BYTEBOOL;
  GLint     = Integer;
  GLsizei   = Integer;
  GLuint    = Cardinal;
  GLfloat   = Single;
  GLenum    = Cardinal;

  PGLvoid    = Pointer;
  PGLboolean = ^GLboolean;
  PGLint     = ^GLint;
  PGLuint    = ^GLuint;
  PGLfloat   = ^GLfloat;

  TglCompressedTexImage1D  = procedure(target: GLenum; level: GLint; internalformat: GLenum; width: GLsizei; border: GLint; imageSize: GLsizei; const data: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglCompressedTexImage2D  = procedure(target: GLenum; level: GLint; internalformat: GLenum; width: GLsizei; height: GLsizei; border: GLint; imageSize: GLsizei; const data: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetCompressedTexImage = procedure(target: GLenum; level: GLint; img: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

{$IF DEFINED(GLB_WIN)}
  TwglGetProcAddress = function (ProcName: PAnsiChar): Pointer; stdcall;
{$ELSEIF DEFINED(GLB_LINUX)}
  TglXGetProcAddress = function(ProcName: PAnsiChar): Pointer; cdecl;
  TglXGetProcAddressARB = function(const name: PAnsiChar): pointer; cdecl;
{$IFEND}

{$IF DEFINED(GLB_NATIVE_OGL_DYNAMIC)}
  TglEnable  = procedure(cap: GLenum); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglDisable = procedure(cap: GLenum); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TglGetString   = function(name: GLenum): PAnsiChar; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetIntegerv = procedure(pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TglTexParameteri          = procedure(target: GLenum; pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglTexParameteriv         = procedure(target: GLenum; pname: GLenum; const params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglTexParameterfv         = procedure(target: GLenum; pname: GLenum; const params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetTexParameteriv      = procedure(target: GLenum; pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetTexParameterfv      = procedure(target: GLenum; pname: GLenum; params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetTexLevelParameteriv = procedure(target: GLenum; level: GLint; pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetTexLevelParameterfv = procedure(target: GLenum; level: GLint; pname: GLenum; params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TglTexGeni        = procedure(coord: GLenum; pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGenTextures    = procedure(n: GLsizei; textures: PGLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglBindTexture    = procedure(target: GLenum; texture: GLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglDeleteTextures = procedure(n: GLsizei; const textures: PGLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TglAreTexturesResident = function(n: GLsizei; const textures: PGLuint; residences: PGLboolean): GLboolean; {$IFDEF DGL_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglReadPixels          = procedure(x: GLint; y: GLint; width: GLsizei; height: GLsizei; format: GLenum; _type: GLenum; pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglPixelStorei         = procedure(pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TglTexImage1D  = procedure(target: GLenum; level: GLint; internalformat: GLint; width: GLsizei; border: GLint; format: GLenum; _type: GLenum; const pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglTexImage2D  = procedure(target: GLenum; level: GLint; internalformat: GLint; width: GLsizei; height: GLsizei; border: GLint; format: GLenum; _type: GLenum; const pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TglGetTexImage = procedure(target: GLenum; level: GLint; format: GLenum; _type: GLenum; pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

  TgluBuild1DMipmaps = function(target: GLEnum; components, width: GLint; format, atype: GLEnum; const data: Pointer): GLint; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}
  TgluBuild2DMipmaps = function(target: GLEnum; components, width, height: GLint; format, atype: GLEnum; const Data: Pointer): GLint; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF}

{$ELSEIF DEFINED(GLB_NATIVE_OGL_STATIC)}
  procedure glEnable(cap: GLenum); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glDisable(cap: GLenum); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  function glGetString(name: GLenum): PAnsiChar; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetIntegerv(pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  procedure glTexParameteri(target: GLenum; pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glTexParameteriv(target: GLenum; pname: GLenum; const params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glTexParameterfv(target: GLenum; pname: GLenum; const params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetTexParameteriv(target: GLenum; pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetTexParameterfv(target: GLenum; pname: GLenum; params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetTexLevelParameteriv(target: GLenum; level: GLint; pname: GLenum; params: PGLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetTexLevelParameterfv(target: GLenum; level: GLint; pname: GLenum; params: PGLfloat); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  procedure glTexGeni(coord: GLenum; pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGenTextures(n: GLsizei; textures: PGLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glBindTexture(target: GLenum; texture: GLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glDeleteTextures(n: GLsizei; const textures: PGLuint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  function  glAreTexturesResident(n: GLsizei; const textures: PGLuint; residences: PGLboolean): GLboolean; {$IFDEF DGL_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glReadPixels(x: GLint; y: GLint; width: GLsizei; height: GLsizei; format: GLenum; _type: GLenum; pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glPixelStorei(pname: GLenum; param: GLint); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  procedure glTexImage1D(target: GLenum; level: GLint; internalformat: GLint; width: GLsizei; border: GLint; format: GLenum; _type: GLenum; const pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glTexImage2D(target: GLenum; level: GLint; internalformat: GLint; width: GLsizei; height: GLsizei; border: GLint; format: GLenum; _type: GLenum; const pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;
  procedure glGetTexImage(target: GLenum; level: GLint; format: GLenum; _type: GLenum; pixels: PGLvoid); {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libopengl;

  function gluBuild1DMipmaps(target: GLEnum; components, width: GLint; format, atype: GLEnum; const data: Pointer): GLint; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libglu;
  function gluBuild2DMipmaps(target: GLEnum; components, width, height: GLint; format, atype: GLEnum; const Data: Pointer): GLint; {$IFDEF GLB_WIN}stdcall; {$ELSE}cdecl; {$ENDIF} external libglu;
{$IFEND}

var
  GL_VERSION_1_2,
  GL_VERSION_1_3,
  GL_VERSION_1_4,
  GL_VERSION_2_0,
  GL_VERSION_3_3,

  GL_SGIS_generate_mipmap,

  GL_ARB_texture_border_clamp,
  GL_ARB_texture_mirrored_repeat,
  GL_ARB_texture_rectangle,
  GL_ARB_texture_non_power_of_two,
  GL_ARB_texture_swizzle,
  GL_ARB_texture_cube_map,

  GL_IBM_texture_mirrored_repeat,

  GL_NV_texture_rectangle,

  GL_EXT_texture_edge_clamp,
  GL_EXT_texture_rectangle,
  GL_EXT_texture_swizzle,
  GL_EXT_texture_cube_map,
  GL_EXT_texture_filter_anisotropic: Boolean;

  glCompressedTexImage1D: TglCompressedTexImage1D;
  glCompressedTexImage2D: TglCompressedTexImage2D;
  glGetCompressedTexImage: TglGetCompressedTexImage;

{$IF DEFINED(GLB_WIN)}
  wglGetProcAddress: TwglGetProcAddress;
{$ELSEIF DEFINED(GLB_LINUX)}
  glXGetProcAddress: TglXGetProcAddress;
  glXGetProcAddressARB: TglXGetProcAddress;
{$IFEND}

{$IFDEF GLB_NATIVE_OGL_DYNAMIC}
  glEnable: TglEnable;
  glDisable: TglDisable;

  glGetString: TglGetString;
  glGetIntegerv: TglGetIntegerv;

  glTexParameteri: TglTexParameteri;
  glTexParameteriv: TglTexParameteriv;
  glTexParameterfv: TglTexParameterfv;
  glGetTexParameteriv: TglGetTexParameteriv;
  glGetTexParameterfv: TglGetTexParameterfv;
  glGetTexLevelParameteriv: TglGetTexLevelParameteriv;
  glGetTexLevelParameterfv: TglGetTexLevelParameterfv;

  glTexGeni: TglTexGeni;
  glGenTextures: TglGenTextures;
  glBindTexture: TglBindTexture;
  glDeleteTextures: TglDeleteTextures;

  glAreTexturesResident: TglAreTexturesResident;
  glReadPixels: TglReadPixels;
  glPixelStorei: TglPixelStorei;

  glTexImage1D: TglTexImage1D;
  glTexImage2D: TglTexImage2D;
  glGetTexImage: TglGetTexImage;

  gluBuild1DMipmaps: TgluBuild1DMipmaps;
  gluBuild2DMipmaps: TgluBuild2DMipmaps;
{$ENDIF}
{$ENDIF}

type
////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmapFormat = (
    tfEmpty = 0, //must be smallest value!

    tfAlpha4,
    tfAlpha8,
    tfAlpha12,
    tfAlpha16,

    tfLuminance4,
    tfLuminance8,
    tfLuminance12,
    tfLuminance16,

    tfLuminance4Alpha4,
    tfLuminance6Alpha2,
    tfLuminance8Alpha8,
    tfLuminance12Alpha4,
    tfLuminance12Alpha12,
    tfLuminance16Alpha16,

    tfR3G3B2,
    tfRGB4,
    tfR5G6B5,
    tfRGB5,
    tfRGB8,
    tfRGB10,
    tfRGB12,
    tfRGB16,

    tfRGBA2,
    tfRGBA4,
    tfRGB5A1,
    tfRGBA8,
    tfRGB10A2,
    tfRGBA12,
    tfRGBA16,

    tfBGR4,
    tfB5G6R5,
    tfBGR5,
    tfBGR8,
    tfBGR10,
    tfBGR12,
    tfBGR16,

    tfBGRA2,
    tfBGRA4,
    tfBGR5A1,
    tfBGRA8,
    tfBGR10A2,
    tfBGRA12,
    tfBGRA16,

    tfDepth16,
    tfDepth24,
    tfDepth32,

    tfS3tcDtx1RGBA,
    tfS3tcDtx3RGBA,
    tfS3tcDtx5RGBA
  );

  TglBitmapFileType = (
     {$IFDEF GLB_SUPPORT_PNG_WRITE} ftPNG,  {$ENDIF}
     {$IFDEF GLB_SUPPORT_JPEG_WRITE}ftJPEG, {$ENDIF}
     ftDDS,
     ftTGA,
     ftBMP);
   TglBitmapFileTypes = set of TglBitmapFileType;

   TglBitmapMipMap = (
     mmNone,
     mmMipmap,
     mmMipmapGlu);

   TglBitmapNormalMapFunc = (
     nm4Samples,
     nmSobel,
     nm3x3,
     nm5x5);

 ////////////////////////////////////////////////////////////////////////////////////////////////////
   EglBitmap                  = class(Exception);
   EglBitmapNotSupported      = class(Exception);
   EglBitmapSizeToLarge       = class(EglBitmap);
   EglBitmapNonPowerOfTwo     = class(EglBitmap);
   EglBitmapUnsupportedFormat = class(EglBitmap)
     constructor Create(const aFormat: TglBitmapFormat); overload;
     constructor Create(const aMsg: String; const aFormat: TglBitmapFormat); overload;
   end;

////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmapColorRec = packed record
  case Integer of
    0: (r, g, b, a: Cardinal);
    1: (arr: array[0..3] of Cardinal);
  end;

  TglBitmapPixelData = packed record
    Data, Range: TglBitmapColorRec;
    Format: TglBitmapFormat;
  end;
  PglBitmapPixelData = ^TglBitmapPixelData;

////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmapPixelPositionFields = set of (ffX, ffY);
  TglBitmapPixelPosition = record
    Fields : TglBitmapPixelPositionFields;
    X : Word;
    Y : Word;
  end;

  TglBitmapFormatDescriptor = class(TObject)
  protected
    function GetIsCompressed: Boolean; virtual; abstract;
    function GetHasAlpha:     Boolean; virtual; abstract;

    function GetglDataFormat:     GLenum;  virtual; abstract;
    function GetglFormat:         GLenum;  virtual; abstract;
    function GetglInternalFormat: GLenum;  virtual; abstract;
  public
    property IsCompressed: Boolean read GetIsCompressed;
    property HasAlpha:     Boolean read GetHasAlpha;

    property glFormat:         GLenum  read GetglFormat;
    property glInternalFormat: GLenum  read GetglInternalFormat;
    property glDataFormat:     GLenum  read GetglDataFormat;
  end;

////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmap = class;
  TglBitmapFunctionRec = record
    Sender:   TglBitmap;
    Size:     TglBitmapPixelPosition;
    Position: TglBitmapPixelPosition;
    Source:   TglBitmapPixelData;
    Dest:     TglBitmapPixelData;
    Args:     Pointer;
  end;
  TglBitmapFunction = procedure(var FuncRec: TglBitmapFunctionRec);

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmap = class
  private
    function GetFormatDesc: TglBitmapFormatDescriptor;
  protected
    fID: GLuint;
    fTarget: GLuint;
    fAnisotropic: Integer;
    fDeleteTextureOnFree: Boolean;
    fFreeDataAfterGenTexture: Boolean;
    fData: PByte;
    fIsResident: Boolean;
    fBorderColor: array[0..3] of Single;

    fDimension: TglBitmapPixelPosition;
    fMipMap: TglBitmapMipMap;
    fFormat: TglBitmapFormat;

    // Mapping
    fPixelSize: Integer;
    fRowSize: Integer;

    // Filtering
    fFilterMin: GLenum;
    fFilterMag: GLenum;

    // TexturWarp
    fWrapS: GLenum;
    fWrapT: GLenum;
    fWrapR: GLenum;

    //Swizzle
    fSwizzle: array[0..3] of GLenum;

    // CustomData
    fFilename: String;
    fCustomName: String;
    fCustomNameW: WideString;
    fCustomData: Pointer;

    //Getter
    function GetWidth:  Integer; virtual;
    function GetHeight: Integer; virtual;

    function GetFileWidth:  Integer; virtual;
    function GetFileHeight: Integer; virtual;

    //Setter
    procedure SetCustomData(const aValue: Pointer);
    procedure SetCustomName(const aValue: String);
    procedure SetCustomNameW(const aValue: WideString);
    procedure SetDeleteTextureOnFree(const aValue: Boolean);
    procedure SetFormat(const aValue: TglBitmapFormat);
    procedure SetFreeDataAfterGenTexture(const aValue: Boolean);
    procedure SetID(const aValue: Cardinal);
    procedure SetMipMap(const aValue: TglBitmapMipMap);
    procedure SetTarget(const aValue: Cardinal);
    procedure SetAnisotropic(const aValue: Integer);

    procedure CreateID;
    procedure SetupParameters(out aBuildWithGlu: Boolean);
    procedure SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
      const aWidth: Integer = -1; const aHeight: Integer = -1); virtual;  //be careful, aData could be freed by this method
    procedure GenTexture(const aTestTextureSize: Boolean = true); virtual; abstract;

    function FlipHorz: Boolean; virtual;
    function FlipVert: Boolean; virtual;

    property Width:  Integer read GetWidth;
    property Height: Integer read GetHeight;

    property FileWidth:  Integer read GetFileWidth;
    property FileHeight: Integer read GetFileHeight;
  public
    //Properties
    property ID:           Cardinal        read fID          write SetID;
    property Target:       Cardinal        read fTarget      write SetTarget;
    property Format:       TglBitmapFormat read fFormat      write SetFormat;
    property MipMap:       TglBitmapMipMap read fMipMap      write SetMipMap;
    property Anisotropic:  Integer         read fAnisotropic write SetAnisotropic;

    property FormatDesc:   TglBitmapFormatDescriptor read GetFormatDesc;

    property Filename:    String     read fFilename;
    property CustomName:  String     read fCustomName  write SetCustomName;
    property CustomNameW: WideString read fCustomNameW write SetCustomNameW;
    property CustomData:  Pointer    read fCustomData  write SetCustomData;

    property DeleteTextureOnFree:     Boolean read fDeleteTextureOnFree     write SetDeleteTextureOnFree;
    property FreeDataAfterGenTexture: Boolean read fFreeDataAfterGenTexture write SetFreeDataAfterGenTexture;

    property Dimension:  TglBitmapPixelPosition  read fDimension;
    property Data:       PByte                   read fData;
    property IsResident: Boolean                 read fIsResident;

    procedure AfterConstruction; override;
    procedure BeforeDestruction; override;

    procedure PrepareResType(var aResource: String; var aResType: PChar);

    //Load
    procedure LoadFromFile(const aFilename: String);
    procedure LoadFromStream(const aStream: TStream); virtual;
    procedure LoadFromFunc(const aSize: TglBitmapPixelPosition; const aFunc: TglBitmapFunction;
      const aFormat: TglBitmapFormat; const aArgs: Pointer = nil);
    procedure LoadFromResource(const aInstance: Cardinal; aResource: String; aResType: PChar = nil);
    procedure LoadFromResourceID(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar);

    //Save
    procedure SaveToFile(const aFileName: String; const aFileType: TglBitmapFileType);
    procedure SaveToStream(const aStream: TStream; const aFileType: TglBitmapFileType); virtual;

    //Convert
    function AddFunc(const aFunc: TglBitmapFunction; const aCreateTemp: Boolean; const aArgs: Pointer = nil): Boolean; overload;
    function AddFunc(const aSource: TglBitmap; const aFunc: TglBitmapFunction; aCreateTemp: Boolean;
      const aFormat: TglBitmapFormat; const aArgs: Pointer = nil): Boolean; overload;
  public
    //Alpha & Co
    {$IFDEF GLB_SDL}
    function AssignToSurface(out aSurface: PSDL_Surface): Boolean;
    function AssignFromSurface(const aSurface: PSDL_Surface): Boolean;
    function AssignAlphaToSurface(out aSurface: PSDL_Surface): Boolean;
    function AddAlphaFromSurface(const aSurface: PSDL_Surface; const aFunc: TglBitmapFunction = nil;
      const aArgs: Pointer = nil): Boolean;
    {$ENDIF}

    {$IFDEF GLB_DELPHI}
    function AssignToBitmap(const aBitmap: TBitmap): Boolean;
    function AssignFromBitmap(const aBitmap: TBitmap): Boolean;
    function AssignAlphaToBitmap(const aBitmap: TBitmap): Boolean;
    function AddAlphaFromBitmap(const aBitmap: TBitmap; const aFunc: TglBitmapFunction = nil;
      const aArgs: Pointer = nil): Boolean;
    {$ENDIF}

    {$IFDEF GLB_LAZARUS}
    function AssignToLazIntfImage(const aImage: TLazIntfImage): Boolean;
    function AssignFromLazIntfImage(const aImage: TLazIntfImage): Boolean;
    function AssignAlphaToLazIntfImage(const aImage: TLazIntfImage): Boolean;
    function AddAlphaFromLazIntfImage(const aImage: TLazIntfImage; const aFunc: TglBitmapFunction = nil;
      const aArgs: Pointer = nil): Boolean;
    {$ENDIF}

    function AddAlphaFromResource(const aInstance: Cardinal; aResource: String; aResType: PChar = nil;
      const aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;
    function AddAlphaFromResourceID(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar;
      const aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;

    function AddAlphaFromFunc(const aFunc: TglBitmapFunction; const aArgs: Pointer = nil): Boolean; virtual;
    function AddAlphaFromFile(const aFileName: String; const aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;
    function AddAlphaFromStream(const aStream: TStream; const aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;
    function AddAlphaFromGlBitmap(const aBitmap: TglBitmap; aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;

    function AddAlphaFromColorKey(const aRed, aGreen, aBlue: Byte; const aDeviation: Byte = 0): Boolean;
    function AddAlphaFromColorKeyRange(const aRed, aGreen, aBlue: Cardinal; const aDeviation: Cardinal = 0): Boolean;
    function AddAlphaFromColorKeyFloat(const aRed, aGreen, aBlue: Single; const aDeviation: Single = 0): Boolean;

    function AddAlphaFromValue(const aAlpha: Byte): Boolean;
    function AddAlphaFromValueRange(const aAlpha: Cardinal): Boolean;
    function AddAlphaFromValueFloat(const aAlpha: Single): Boolean;

    function RemoveAlpha: Boolean; virtual;
  public
    //Common
    function Clone: TglBitmap;
    function ConvertTo(const aFormat: TglBitmapFormat): Boolean; virtual;
    procedure Invert(const aUseRGB: Boolean = true; const aUseAlpha: Boolean = false);
    procedure SetBorderColor(const aRed, aGreen, aBlue, aAlpha: Single);
    procedure FreeData;

    //ColorFill
    procedure FillWithColor(const aRed, aGreen, aBlue: Byte; const aAlpha: Byte = 255);
    procedure FillWithColorRange(const aRed, aGreen, aBlue: Cardinal; const aAlpha: Cardinal = $FFFFFFFF);
    procedure FillWithColorFloat(const aRed, aGreen, aBlue: Single; const aAlpha : Single = 1);

    //TexParameters
    procedure SetFilter(const aMin, aMag: GLenum);
    procedure SetWrap(
      const S: GLenum = GL_CLAMP_TO_EDGE;
      const T: GLenum = GL_CLAMP_TO_EDGE;
      const R: GLenum = GL_CLAMP_TO_EDGE);
    procedure SetSwizzle(const r, g, b, a: GLenum);

    procedure Bind(const aEnableTextureUnit: Boolean = true); virtual;
    procedure Unbind(const aDisableTextureUnit: Boolean = true); virtual;

    //Constructors
    constructor Create; overload;
    constructor Create(const aFileName: String); overload;
    constructor Create(const aStream: TStream); overload;
    constructor Create(const aSize: TglBitmapPixelPosition; const aFormat: TglBitmapFormat); overload;
    constructor Create(const aSize: TglBitmapPixelPosition; const aFormat: TglBitmapFormat; const aFunc: TglBitmapFunction; const aArgs: Pointer = nil); overload;
    constructor Create(const aInstance: Cardinal; const aResource: String; const aResType: PChar = nil); overload;
    constructor Create(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar); overload;
  private
    {$IFDEF GLB_SUPPORT_PNG_READ}  function  LoadPNG(const aStream: TStream): Boolean; virtual; {$ENDIF}
    {$ifdef GLB_SUPPORT_PNG_WRITE} procedure SavePNG(const aStream: TStream); virtual; {$ENDIF}

    {$IFDEF GLB_SUPPORT_JPEG_READ}  function  LoadJPEG(const aStream: TStream): Boolean; virtual; {$ENDIF}
    {$IFDEF GLB_SUPPORT_JPEG_WRITE} procedure SaveJPEG(const aStream: TStream); virtual; {$ENDIF}

    function LoadBMP(const aStream: TStream): Boolean; virtual;
    procedure SaveBMP(const aStream: TStream); virtual;

    function LoadTGA(const aStream: TStream): Boolean; virtual;
    procedure SaveTGA(const aStream: TStream); virtual;

    function LoadDDS(const aStream: TStream): Boolean; virtual;
    procedure SaveDDS(const aStream: TStream); virtual;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmap1D = class(TglBitmap)
  protected
    procedure SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
      const aWidth: Integer = - 1; const aHeight: Integer = - 1); override;
    procedure UploadData(const aBuildWithGlu: Boolean);
  public
    property Width;
    procedure AfterConstruction; override;
    function FlipHorz: Boolean; override;
    procedure GenTexture(const aTestTextureSize: Boolean = true); override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmap2D = class(TglBitmap)
  protected
    fLines: array of PByte;
    function GetScanline(const aIndex: Integer): Pointer;
    procedure SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
      const aWidth: Integer = - 1; const aHeight: Integer = - 1); override;
    procedure UploadData(const aTarget: GLenum; const aBuildWithGlu: Boolean);
  public
    property Width;
    property Height;
    property Scanline[const aIndex: Integer]: Pointer read GetScanline;

    procedure AfterConstruction; override;

    procedure GrabScreen(const aTop, aLeft, aRight, aBottom: Integer; const aFormat: TglBitmapFormat);
    procedure GetDataFromTexture;
    procedure GenTexture(const aTestTextureSize: Boolean = true); override;

    function FlipHorz: Boolean; override;
    function FlipVert: Boolean; override;

    procedure ToNormalMap(const aFunc: TglBitmapNormalMapFunc = nm3x3;
      const aScale: Single = 2; const aUseAlpha: Boolean = false);
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmapCubeMap = class(TglBitmap2D)
  protected
    fGenMode: Integer;
    procedure GenTexture(const aTestTextureSize: Boolean = true); reintroduce;
  public
    procedure AfterConstruction; override;
    procedure GenerateCubeMap(const aCubeTarget: Cardinal; const aTestTextureSize: Boolean = true);
    procedure Bind(const aEnableTexCoordsGen: Boolean = true; const aEnableTextureUnit: Boolean = true); reintroduce; virtual;
    procedure Unbind(const aDisableTexCoordsGen: Boolean = true; const aDisableTextureUnit: Boolean = true); reintroduce; virtual;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TglBitmapNormalMap = class(TglBitmapCubeMap)
  public
    procedure AfterConstruction; override;
    procedure GenerateNormalMap(const aSize: Integer = 32; const aTestTextureSize: Boolean = true);
  end;

const
  NULL_SIZE: TglBitmapPixelPosition = (Fields: []; X: 0; Y: 0);

procedure glBitmapSetDefaultDeleteTextureOnFree(const aDeleteTextureOnFree: Boolean);
procedure glBitmapSetDefaultFreeDataAfterGenTexture(const aFreeData: Boolean);
procedure glBitmapSetDefaultMipmap(const aValue: TglBitmapMipMap);
procedure glBitmapSetDefaultFormat(const aFormat: TglBitmapFormat);
procedure glBitmapSetDefaultFilter(const aMin, aMag: Integer);
procedure glBitmapSetDefaultWrap(
  const S: Cardinal = GL_CLAMP_TO_EDGE;
  const T: Cardinal = GL_CLAMP_TO_EDGE;
  const R: Cardinal = GL_CLAMP_TO_EDGE);

function glBitmapGetDefaultDeleteTextureOnFree: Boolean;
function glBitmapGetDefaultFreeDataAfterGenTexture: Boolean;
function glBitmapGetDefaultMipmap: TglBitmapMipMap;
function glBitmapGetDefaultFormat: TglBitmapFormat;
procedure glBitmapGetDefaultFilter(var aMin, aMag: Cardinal);
procedure glBitmapGetDefaultTextureWrap(var S, T, R: Cardinal);

function glBitmapPosition(X: Integer = -1; Y: Integer = -1): TglBitmapPixelPosition;
function glBitmapColorRec(const r, g, b, a: Cardinal): TglBitmapColorRec;
function glBitmapColorRecCmp(const r1, r2: TglBitmapColorRec): Boolean;

var
  glBitmapDefaultDeleteTextureOnFree: Boolean;
  glBitmapDefaultFreeDataAfterGenTextures: Boolean;
  glBitmapDefaultFormat: TglBitmapFormat;
  glBitmapDefaultMipmap: TglBitmapMipMap;
  glBitmapDefaultFilterMin: Cardinal;
  glBitmapDefaultFilterMag: Cardinal;
  glBitmapDefaultWrapS: Cardinal;
  glBitmapDefaultWrapT: Cardinal;
  glBitmapDefaultWrapR: Cardinal;
  glDefaultSwizzle: array[0..3] of GLenum;

{$IFDEF GLB_DELPHI}
function CreateGrayPalette: HPALETTE;
{$ENDIF}

implementation

uses
  Math, syncobjs, typinfo;

type
{$IFNDEF fpc}
  QWord   = System.UInt64;
  PQWord  = ^QWord;

  PtrInt  = Longint;
  PtrUInt = DWord;
{$ENDIF}

////////////////////////////////////////////////////////////////////////////////////////////////////
  TShiftRec = packed record
  case Integer of
    0: (r, g, b, a: Byte);
    1: (arr: array[0..3] of Byte);
  end;

  TFormatDescriptor = class(TglBitmapFormatDescriptor)
  private
    function GetRedMask: QWord;
    function GetGreenMask: QWord;
    function GetBlueMask: QWord;
    function GetAlphaMask: QWord;
  protected
    fFormat: TglBitmapFormat;
    fWithAlpha: TglBitmapFormat;
    fWithoutAlpha: TglBitmapFormat;
    fRGBInverted: TglBitmapFormat;
    fUncompressed: TglBitmapFormat;
    fPixelSize: Single;
    fIsCompressed: Boolean;

    fRange: TglBitmapColorRec;
    fShift: TShiftRec;

    fglFormat:         GLenum;
    fglInternalFormat: GLenum;
    fglDataFormat:     GLenum;

    function GetIsCompressed: Boolean; override;
    function GetHasAlpha: Boolean; override;

    function GetglFormat: GLenum; override;
    function GetglInternalFormat: GLenum; override;
    function GetglDataFormat: GLenum; override;

    function GetComponents: Integer; virtual;
  public
    property Format:       TglBitmapFormat read fFormat;
    property WithAlpha:    TglBitmapFormat read fWithAlpha;
    property WithoutAlpha: TglBitmapFormat read fWithoutAlpha;
    property RGBInverted:  TglBitmapFormat read fRGBInverted;
    property Components:   Integer         read GetComponents;
    property PixelSize:    Single          read fPixelSize;

    property Range: TglBitmapColorRec read fRange;
    property Shift: TShiftRec         read fShift;

    property RedMask:   QWord read GetRedMask;
    property GreenMask: QWord read GetGreenMask;
    property BlueMask:  QWord read GetBlueMask;
    property AlphaMask: QWord read GetAlphaMask;

    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); virtual; abstract;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); virtual; abstract;

    function GetSize(const aSize: TglBitmapPixelPosition): Integer; overload; virtual;
    function GetSize(const aWidth, aHeight: Integer): Integer; overload; virtual;

    function CreateMappingData: Pointer; virtual;
    procedure FreeMappingData(var aMappingData: Pointer); virtual;

    function IsEmpty:  Boolean; virtual;
    function MaskMatch(const aRedMask, aGreenMask, aBlueMask, aAlphaMask: QWord): Boolean; virtual;

    procedure PreparePixel(out aPixel: TglBitmapPixelData); virtual;

    constructor Create; virtual;
  public
    class procedure Init;
    class function Get(const aFormat: TglBitmapFormat): TFormatDescriptor;
    class function GetWithAlpha(const aFormat: TglBitmapFormat): TFormatDescriptor;
    class procedure Clear;
    class procedure Finalize;
  end;
  TFormatDescriptorClass = class of TFormatDescriptor;

  TfdEmpty = class(TFormatDescriptor);

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TfdAlpha_UB1 = class(TFormatDescriptor) //1* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdLuminance_UB1 = class(TFormatDescriptor) //1* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdUniversal_UB1 = class(TFormatDescriptor) //1* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdLuminanceAlpha_UB2 = class(TfdLuminance_UB1) //2* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdRGB_UB3 = class(TFormatDescriptor) //3* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdBGR_UB3 = class(TFormatDescriptor) //3* unsigned byte (inverse)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdRGBA_UB4 = class(TfdRGB_UB3) //4* unsigned byte
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdBGRA_UB4 = class(TfdBGR_UB3) //4* unsigned byte  (inverse)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TfdAlpha_US1 = class(TFormatDescriptor) //1* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdLuminance_US1 = class(TFormatDescriptor) //1* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdUniversal_US1 = class(TFormatDescriptor) //1* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdDepth_US1 = class(TFormatDescriptor) //1* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdLuminanceAlpha_US2 = class(TfdLuminance_US1) //2* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdRGB_US3 = class(TFormatDescriptor) //3* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdBGR_US3 = class(TFormatDescriptor) //3* unsigned short (inverse)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdRGBA_US4 = class(TfdRGB_US3) //4* unsigned short
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdBGRA_US4 = class(TfdBGR_US3) //4* unsigned short (inverse)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TfdUniversal_UI1 = class(TFormatDescriptor) //1* unsigned int
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdDepth_UI1 = class(TFormatDescriptor) //1* unsigned int
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TfdAlpha4 = class(TfdAlpha_UB1)
    constructor Create; override;
  end;

  TfdAlpha8 = class(TfdAlpha_UB1)
    constructor Create; override;
  end;

  TfdAlpha12 = class(TfdAlpha_US1)
    constructor Create; override;
  end;

  TfdAlpha16 = class(TfdAlpha_US1)
    constructor Create; override;
  end;

  TfdLuminance4 = class(TfdLuminance_UB1)
    constructor Create; override;
  end;

  TfdLuminance8 = class(TfdLuminance_UB1)
    constructor Create; override;
  end;

  TfdLuminance12 = class(TfdLuminance_US1)
    constructor Create; override;
  end;

  TfdLuminance16 = class(TfdLuminance_US1)
    constructor Create; override;
  end;

  TfdLuminance4Alpha4 = class(TfdLuminanceAlpha_UB2)
    constructor Create; override;
  end;

  TfdLuminance6Alpha2 = class(TfdLuminanceAlpha_UB2)
    constructor Create; override;
  end;

  TfdLuminance8Alpha8 = class(TfdLuminanceAlpha_UB2)
    constructor Create; override;
  end;

  TfdLuminance12Alpha4 = class(TfdLuminanceAlpha_US2)
    constructor Create; override;
  end;

  TfdLuminance12Alpha12 = class(TfdLuminanceAlpha_US2)
    constructor Create; override;
  end;

  TfdLuminance16Alpha16 = class(TfdLuminanceAlpha_US2)
    constructor Create; override;
  end;

  TfdR3G3B2 = class(TfdUniversal_UB1)
    constructor Create; override;
  end;

  TfdRGB4 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdR5G6B5 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdRGB5 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdRGB8 = class(TfdRGB_UB3)
    constructor Create; override;
  end;

  TfdRGB10 = class(TfdUniversal_UI1)
    constructor Create; override;
  end;

  TfdRGB12 = class(TfdRGB_US3)
    constructor Create; override;
  end;

  TfdRGB16 = class(TfdRGB_US3)
    constructor Create; override;
  end;

  TfdRGBA2 = class(TfdRGBA_UB4)
    constructor Create; override;
  end;

  TfdRGBA4 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdRGB5A1 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdRGBA8 = class(TfdRGBA_UB4)
    constructor Create; override;
  end;

  TfdRGB10A2 = class(TfdUniversal_UI1)
    constructor Create; override;
  end;

  TfdRGBA12 = class(TfdRGBA_US4)
    constructor Create; override;
  end;

  TfdRGBA16 = class(TfdRGBA_US4)
    constructor Create; override;
  end;

  TfdBGR4 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdB5G6R5 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdBGR5 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdBGR8 = class(TfdBGR_UB3)
    constructor Create; override;
  end;

  TfdBGR10 = class(TfdUniversal_UI1)
    constructor Create; override;
  end;

  TfdBGR12 = class(TfdBGR_US3)
    constructor Create; override;
  end;

  TfdBGR16 = class(TfdBGR_US3)
    constructor Create; override;
  end;

  TfdBGRA2 = class(TfdBGRA_UB4)
    constructor Create; override;
  end;

  TfdBGRA4 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdBGR5A1 = class(TfdUniversal_US1)
    constructor Create; override;
  end;

  TfdBGRA8 = class(TfdBGRA_UB4)
    constructor Create; override;
  end;

  TfdBGR10A2 = class(TfdUniversal_UI1)
    constructor Create; override;
  end;

  TfdBGRA12 = class(TfdBGRA_US4)
    constructor Create; override;
  end;

  TfdBGRA16 = class(TfdBGRA_US4)
    constructor Create; override;
  end;

  TfdDepth16 = class(TfdDepth_US1)
    constructor Create; override;
  end;

  TfdDepth24 = class(TfdDepth_UI1)
    constructor Create; override;
  end;

  TfdDepth32 = class(TfdDepth_UI1)
    constructor Create; override;
  end;

  TfdS3tcDtx1RGBA = class(TFormatDescriptor)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdS3tcDtx3RGBA = class(TFormatDescriptor)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

  TfdS3tcDtx5RGBA = class(TFormatDescriptor)
    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    constructor Create; override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TbmpBitfieldFormat = class(TFormatDescriptor)
  private
    procedure SetRedMask  (const aValue: QWord);
    procedure SetGreenMask(const aValue: QWord);
    procedure SetBlueMask (const aValue: QWord);
    procedure SetAlphaMask(const aValue: QWord);

    procedure Update(aMask: QWord; out aRange: Cardinal; out aShift: Byte);
  public
    property RedMask:   QWord read GetRedMask   write SetRedMask;
    property GreenMask: QWord read GetGreenMask write SetGreenMask;
    property BlueMask:  QWord read GetBlueMask  write SetBlueMask;
    property AlphaMask: QWord read GetAlphaMask write SetAlphaMask;

    property PixelSize: Single read fPixelSize write fPixelSize;

    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TbmpColorTableEnty = packed record
    b, g, r, a: Byte;
  end;
  TbmpColorTable = array of TbmpColorTableEnty;
  TbmpColorTableFormat = class(TFormatDescriptor)
  private
    fColorTable: TbmpColorTable;
  public
    property PixelSize:  Single            read fPixelSize  write fPixelSize;
    property ColorTable: TbmpColorTable    read fColorTable write fColorTable;
    property Range:      TglBitmapColorRec read fRange      write fRange;
    property Shift:      TShiftRec         read fShift      write fShift;
    property Format:     TglBitmapFormat   read fFormat     write fFormat;

    procedure CreateColorTable;

    procedure Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer); override;
    procedure Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer); override;
    destructor Destroy; override;
  end;

const
  LUMINANCE_WEIGHT_R = 0.30;
  LUMINANCE_WEIGHT_G = 0.59;
  LUMINANCE_WEIGHT_B = 0.11;

  ALPHA_WEIGHT_R = 0.30;
  ALPHA_WEIGHT_G = 0.59;
  ALPHA_WEIGHT_B = 0.11;

  DEPTH_WEIGHT_R = 0.333333333;
  DEPTH_WEIGHT_G = 0.333333333;
  DEPTH_WEIGHT_B = 0.333333333;

  UNSUPPORTED_FORMAT = 'the given format isn''t supported by this function.';

  FORMAT_DESCRIPTOR_CLASSES: array[TglBitmapFormat] of TFormatDescriptorClass = (
    TfdEmpty,

    TfdAlpha4,
    TfdAlpha8,
    TfdAlpha12,
    TfdAlpha16,

    TfdLuminance4,
    TfdLuminance8,
    TfdLuminance12,
    TfdLuminance16,

    TfdLuminance4Alpha4,
    TfdLuminance6Alpha2,
    TfdLuminance8Alpha8,
    TfdLuminance12Alpha4,
    TfdLuminance12Alpha12,
    TfdLuminance16Alpha16,

    TfdR3G3B2,
    TfdRGB4,
    TfdR5G6B5,
    TfdRGB5,
    TfdRGB8,
    TfdRGB10,
    TfdRGB12,
    TfdRGB16,

    TfdRGBA2,
    TfdRGBA4,
    TfdRGB5A1,
    TfdRGBA8,
    TfdRGB10A2,
    TfdRGBA12,
    TfdRGBA16,

    TfdBGR4,
    TfdB5G6R5,
    TfdBGR5,
    TfdBGR8,
    TfdBGR10,
    TfdBGR12,
    TfdBGR16,

    TfdBGRA2,
    TfdBGRA4,
    TfdBGR5A1,
    TfdBGRA8,
    TfdBGR10A2,
    TfdBGRA12,
    TfdBGRA16,

    TfdDepth16,
    TfdDepth24,
    TfdDepth32,

    TfdS3tcDtx1RGBA,
    TfdS3tcDtx3RGBA,
    TfdS3tcDtx5RGBA
  );

var
  FormatDescriptorCS: TCriticalSection;
  FormatDescriptors: array[TglBitmapFormat] of TFormatDescriptor;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor EglBitmapUnsupportedFormat.Create(const aFormat: TglBitmapFormat);
begin
  inherited Create('unsupported format: ' + GetEnumName(TypeInfo(TglBitmapFormat), Integer(aFormat)));
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor EglBitmapUnsupportedFormat.Create(const aMsg: String; const aFormat: TglBitmapFormat);
begin
  inherited Create(aMsg + GetEnumName(TypeInfo(TglBitmapFormat), Integer(aFormat)));
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapPosition(X, Y: Integer): TglBitmapPixelPosition;
begin
  result.Fields := [];

  if X >= 0 then
    result.Fields := result.Fields + [ffX];
  if Y >= 0 then
    result.Fields := result.Fields + [ffY];

  result.X := Max(0, X);
  result.Y := Max(0, Y);
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapColorRec(const r, g, b, a: Cardinal): TglBitmapColorRec;
begin
  result.r := r;
  result.g := g;
  result.b := b;
  result.a := a;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapColorRecCmp(const r1, r2: TglBitmapColorRec): Boolean;
var
  i: Integer;
begin
  result := false;
  for i := 0 to high(r1.arr) do
    if (r1.arr[i] <> r2.arr[i]) then
      exit;
  result := true;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapShiftRec(const r, g, b, a: Byte): TShiftRec;
begin
  result.r := r;
  result.g := g;
  result.b := b;
  result.a := a;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function FormatGetSupportedFiles(const aFormat: TglBitmapFormat): TglBitmapFileTypes;
begin
  result := [];

  if (aFormat in [
        //4 bbp
        tfLuminance4,

        //8bpp
        tfR3G3B2, tfLuminance8,

        //16bpp
        tfRGB4, tfRGB5, tfR5G6B5, tfRGB5A1, tfRGBA4,
        tfBGR4, tfBGR5, tfB5G6R5, tfBGR5A1, tfBGRA4,

        //24bpp
        tfBGR8, tfRGB8,

        //32bpp
        tfRGB10, tfRGB10A2, tfRGBA8,
        tfBGR10, tfBGR10A2, tfBGRA8]) then
    result := result + [ftBMP];

  if (aFormat in [
        //8 bpp
        tfLuminance8, tfAlpha8,

        //16 bpp
        tfLuminance16, tfLuminance8Alpha8,
        tfRGB5, tfRGB5A1, tfRGBA4,
        tfBGR5, tfBGR5A1, tfBGRA4,

        //24 bpp
        tfRGB8, tfBGR8,

        //32 bpp
        tfRGB10A2, tfRGBA8, tfBGR10A2, tfBGRA8]) then
    result := result + [ftTGA];

  if (aFormat in [
        //8 bpp
        tfAlpha8, tfLuminance8, tfLuminance4Alpha4, tfLuminance6Alpha2,
        tfR3G3B2, tfRGBA2, tfBGRA2,

        //16 bpp
        tfAlpha16, tfLuminance16, tfLuminance8Alpha8, tfLuminance12Alpha4,
        tfRGB4, tfR5G6B5, tfRGB5, tfRGBA4, tfRGB5A1,
        tfBGR4, tfB5G6R5, tfBGR5, tfBGRA4, tfBGR5A1,

        //24 bpp
        tfRGB8, tfBGR8,

        //32 bbp
        tfLuminance16Alpha16,
        tfRGBA8, tfRGB10A2,
        tfBGRA8, tfBGR10A2,

        //compressed
        tfS3tcDtx1RGBA, tfS3tcDtx3RGBA, tfS3tcDtx5RGBA]) then
    result := result + [ftDDS];

  {$IFDEF GLB_SUPPORT_PNG_WRITE}
  if aFormat in [
      tfAlpha8, tfLuminance8, tfLuminance8Alpha8,
      tfRGB8, tfRGBA8,
      tfBGR8, tfBGRA8] then
    result := result + [ftPNG];
  {$ENDIF}

  {$IFDEF GLB_SUPPORT_JPEG_WRITE}
  if aFormat in [tfAlpha8, tfLuminance8, tfRGB8, tfBGR8] then
    result := result + [ftJPEG];
  {$ENDIF}
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function IsPowerOfTwo(aNumber: Integer): Boolean;
begin
  while (aNumber and 1) = 0 do
    aNumber := aNumber shr 1;
  result := aNumber = 1;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function GetTopMostBit(aBitSet: QWord): Integer;
begin
  result := 0;
  while aBitSet > 0 do begin
    inc(result);
    aBitSet := aBitSet shr 1;
  end;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function CountSetBits(aBitSet: QWord): Integer;
begin
  result := 0;
  while aBitSet > 0 do begin
    if (aBitSet and 1) = 1 then
      inc(result);
    aBitSet := aBitSet shr 1;
  end;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function LuminanceWeight(const aPixel: TglBitmapPixelData): Cardinal;
begin
  result := Trunc(
    LUMINANCE_WEIGHT_R * aPixel.Data.r +
    LUMINANCE_WEIGHT_G * aPixel.Data.g +
    LUMINANCE_WEIGHT_B * aPixel.Data.b);
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function DepthWeight(const aPixel: TglBitmapPixelData): Cardinal;
begin
  result := Trunc(
    DEPTH_WEIGHT_R * aPixel.Data.r +
    DEPTH_WEIGHT_G * aPixel.Data.g +
    DEPTH_WEIGHT_B * aPixel.Data.b);
end;

{$IFDEF GLB_NATIVE_OGL}
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//OpenGLInitialization///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
var
  GL_LibHandle: Pointer = nil;

function glbGetProcAddress(aProcName: PAnsiChar; aLibHandle: Pointer = nil; const aRaiseOnErr: Boolean = true): Pointer;
begin
  if not Assigned(aLibHandle) then
    aLibHandle := GL_LibHandle;

{$IF DEFINED(GLB_WIN)}
  result := GetProcAddress({%H-}HMODULE(aLibHandle), aProcName);
  if Assigned(result) then
    exit;

  if Assigned(wglGetProcAddress) then
    result := wglGetProcAddress(aProcName);
{$ELSEIF DEFINED(GLB_LINUX)}
  if Assigned(glXGetProcAddress) then begin
    result := glXGetProcAddress(aProcName);
    if Assigned(result) then
      exit;
  end;

  if Assigned(glXGetProcAddressARB) then begin
    result := glXGetProcAddressARB(aProcName);
    if Assigned(result) then
      exit;
  end;

  result := dlsym(aLibHandle, aProcName);
{$IFEND}
  if not Assigned(result) and aRaiseOnErr then
    raise EglBitmap.Create('unable to load procedure form library: ' + aProcName);
end;

{$IFDEF GLB_NATIVE_OGL_DYNAMIC}
var
  GLU_LibHandle: Pointer = nil;
  OpenGLInitialized: Boolean;
  InitOpenGLCS: TCriticalSection;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glbInitOpenGL;

  ////////////////////////////////////////////////////////////////////////////////
  function glbLoadLibrary(const aName: PChar): Pointer;
  begin
    {$IF DEFINED(GLB_WIN)}
    result := {%H-}Pointer(LoadLibrary(aName));
    {$ELSEIF DEFINED(GLB_LINUX)}
    result := dlopen(Name, RTLD_LAZY);
    {$ELSE}
    result := nil;
    {$IFEND}
  end;

  ////////////////////////////////////////////////////////////////////////////////
  function glbFreeLibrary(const aLibHandle: Pointer): Boolean;
  begin
    result := false;
    if not Assigned(aLibHandle) then
      exit;

    {$IF DEFINED(GLB_WIN)}
    Result := FreeLibrary({%H-}HINST(aLibHandle));
    {$ELSEIF DEFINED(GLB_LINUX)}
    Result := dlclose(aLibHandle) = 0;
    {$IFEND}
  end;

begin
  if Assigned(GL_LibHandle) then
    glbFreeLibrary(GL_LibHandle);

  if Assigned(GLU_LibHandle) then
    glbFreeLibrary(GLU_LibHandle);

  GL_LibHandle := glbLoadLibrary(libopengl);
  if not Assigned(GL_LibHandle) then
    raise EglBitmap.Create('unable to load library: ' + libopengl);

  GLU_LibHandle := glbLoadLibrary(libglu);
  if not Assigned(GLU_LibHandle) then
    raise EglBitmap.Create('unable to load library: ' + libglu);

{$IF DEFINED(GLB_WIN)}
  wglGetProcAddress    := glbGetProcAddress('wglGetProcAddress');
{$ELSEIF DEFINED(GLB_LINUX)}
  glXGetProcAddress    := glbGetProcAddress('glXGetProcAddress');
  glXGetProcAddressARB := glbGetProcAddress('glXGetProcAddressARB');
{$IFEND}

  glEnable := glbGetProcAddress('glEnable');
  glDisable := glbGetProcAddress('glDisable');
  glGetString := glbGetProcAddress('glGetString');
  glGetIntegerv := glbGetProcAddress('glGetIntegerv');
  glTexParameteri := glbGetProcAddress('glTexParameteri');
  glTexParameteriv := glbGetProcAddress('glTexParameteriv');
  glTexParameterfv := glbGetProcAddress('glTexParameterfv');
  glGetTexParameteriv := glbGetProcAddress('glGetTexParameteriv');
  glGetTexParameterfv := glbGetProcAddress('glGetTexParameterfv');
  glGetTexLevelParameteriv := glbGetProcAddress('glGetTexLevelParameteriv');
  glGetTexLevelParameterfv := glbGetProcAddress('glGetTexLevelParameterfv');
  glTexGeni := glbGetProcAddress('glTexGeni');
  glGenTextures := glbGetProcAddress('glGenTextures');
  glBindTexture := glbGetProcAddress('glBindTexture');
  glDeleteTextures := glbGetProcAddress('glDeleteTextures');
  glAreTexturesResident := glbGetProcAddress('glAreTexturesResident');
  glReadPixels := glbGetProcAddress('glReadPixels');
  glPixelStorei := glbGetProcAddress('glPixelStorei');
  glTexImage1D := glbGetProcAddress('glTexImage1D');
  glTexImage2D := glbGetProcAddress('glTexImage2D');
  glGetTexImage := glbGetProcAddress('glGetTexImage');

  gluBuild1DMipmaps := glbGetProcAddress('gluBuild1DMipmaps', GLU_LibHandle);
  gluBuild2DMipmaps := glbGetProcAddress('gluBuild2DMipmaps', GLU_LibHandle);
end;
{$ENDIF}

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glbReadOpenGLExtensions;
var
  Buffer: AnsiString;
  MajorVersion, MinorVersion: Integer;

  ///////////////////////////////////////////////////////////////////////////////////////////
  procedure TrimVersionString(aBuffer: AnsiString; out aMajor, aMinor: Integer);
  var
    Separator: Integer;
  begin
    aMinor := 0;
    aMajor := 0;

    Separator := Pos(AnsiString('.'), aBuffer);
    if (Separator > 1) and (Separator < Length(aBuffer)) and
       (aBuffer[Separator - 1] in ['0'..'9']) and
       (aBuffer[Separator + 1] in ['0'..'9']) then begin

      Dec(Separator);
      while (Separator > 0) and (aBuffer[Separator] in ['0'..'9']) do
        Dec(Separator);

      Delete(aBuffer, 1, Separator);
      Separator := Pos(AnsiString('.'), aBuffer) + 1;

      while (Separator <= Length(aBuffer)) and (AnsiChar(aBuffer[Separator]) in ['0'..'9']) do
        Inc(Separator);

      Delete(aBuffer, Separator, 255);
      Separator := Pos(AnsiString('.'), aBuffer);

      aMajor := StrToInt(Copy(String(aBuffer), 1, Separator - 1));
      aMinor := StrToInt(Copy(String(aBuffer), Separator + 1, 1));
    end;
  end;

  ///////////////////////////////////////////////////////////////////////////////////////////
  function CheckExtension(const Extension: AnsiString): Boolean;
  var
    ExtPos: Integer;
  begin
    ExtPos := Pos(Extension, Buffer);
    result := ExtPos > 0;
    if result then
      result := ((ExtPos + Length(Extension) - 1) = Length(Buffer)) or not (Buffer[ExtPos + Length(Extension)] in ['_', 'A'..'Z', 'a'..'z']);
  end;

  ///////////////////////////////////////////////////////////////////////////////////////////
  function CheckVersion(const aMajor, aMinor: Integer): Boolean;
  begin
    result := (MajorVersion > aMajor) or ((MajorVersion = aMajor) and (MinorVersion >= aMinor));
  end;

begin
{$IFDEF GLB_NATIVE_OGL_DYNAMIC}
  InitOpenGLCS.Enter;
  try
    if not OpenGLInitialized then begin
      glbInitOpenGL;
      OpenGLInitialized := true;
    end;
  finally
    InitOpenGLCS.Leave;
  end;
{$ENDIF}

  // Version
  Buffer := glGetString(GL_VERSION);
  TrimVersionString(Buffer, MajorVersion, MinorVersion);

  GL_VERSION_1_2 := CheckVersion(1, 2);
  GL_VERSION_1_3 := CheckVersion(1, 3);
  GL_VERSION_1_4 := CheckVersion(1, 4);
  GL_VERSION_2_0 := CheckVersion(2, 0);
  GL_VERSION_3_3 := CheckVersion(3, 3);

  // Extensions
  Buffer := glGetString(GL_EXTENSIONS);
  GL_ARB_texture_border_clamp       := CheckExtension('GL_ARB_texture_border_clamp');
  GL_ARB_texture_non_power_of_two   := CheckExtension('GL_ARB_texture_non_power_of_two');
  GL_ARB_texture_swizzle            := CheckExtension('GL_ARB_texture_swizzle');
  GL_ARB_texture_cube_map           := CheckExtension('GL_ARB_texture_cube_map');
  GL_ARB_texture_rectangle          := CheckExtension('GL_ARB_texture_rectangle');
  GL_ARB_texture_mirrored_repeat    := CheckExtension('GL_ARB_texture_mirrored_repeat');
  GL_EXT_texture_edge_clamp         := CheckExtension('GL_EXT_texture_edge_clamp');
  GL_EXT_texture_filter_anisotropic := CheckExtension('GL_EXT_texture_filter_anisotropic');
  GL_EXT_texture_rectangle          := CheckExtension('GL_EXT_texture_rectangle');
  GL_EXT_texture_swizzle            := CheckExtension('GL_EXT_texture_swizzle');
  GL_EXT_texture_cube_map           := CheckExtension('GL_EXT_texture_cube_map');
  GL_NV_texture_rectangle           := CheckExtension('GL_NV_texture_rectangle');
  GL_IBM_texture_mirrored_repeat    := CheckExtension('GL_IBM_texture_mirrored_repeat');
  GL_SGIS_generate_mipmap           := CheckExtension('GL_SGIS_generate_mipmap');

  if GL_VERSION_1_3 then begin
    glCompressedTexImage1D  := glbGetProcAddress('glCompressedTexImage1D');
    glCompressedTexImage2D  := glbGetProcAddress('glCompressedTexImage2D');
    glGetCompressedTexImage := glbGetProcAddress('glGetCompressedTexImage');
  end else begin
    glCompressedTexImage1D  := glbGetProcAddress('glCompressedTexImage1DARB',  nil, false);
    glCompressedTexImage2D  := glbGetProcAddress('glCompressedTexImage2DARB',  nil, false);
    glGetCompressedTexImage := glbGetProcAddress('glGetCompressedTexImageARB', nil, false);
  end;
end;
{$ENDIF}

{$IFDEF GLB_SDL_IMAGE}
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// SDL Image Helper /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapRWseek(context: PSDL_RWops; offset: Integer; whence: Integer): Integer; cdecl;
begin
  result := TStream(context^.unknown.data1).Seek(offset, whence);
end;

function glBitmapRWread(context: PSDL_RWops; Ptr: Pointer; size: Integer; maxnum : Integer): Integer; cdecl;
begin
  result := TStream(context^.unknown.data1).Read(Ptr^, size * maxnum);
end;

function glBitmapRWwrite(context: PSDL_RWops; Ptr: Pointer; size: Integer; num: Integer): Integer; cdecl;
begin
  result := TStream(context^.unknown.data1).Write(Ptr^, size * num);
end;

function glBitmapRWclose(context: PSDL_RWops): Integer; cdecl;
begin
  result := 0;
end;

function glBitmapCreateRWops(Stream: TStream): PSDL_RWops;
begin
  result := SDL_AllocRW;

  if result = nil then
    raise EglBitmapException.Create('glBitmapCreateRWops - SDL_AllocRW failed.');

  result^.seek := glBitmapRWseek;
  result^.read := glBitmapRWread;
  result^.write := glBitmapRWwrite;
  result^.close := glBitmapRWclose;
  result^.unknown.data1 := Stream;
end;
{$ENDIF}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultDeleteTextureOnFree(const aDeleteTextureOnFree: Boolean);
begin
  glBitmapDefaultDeleteTextureOnFree := aDeleteTextureOnFree;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultFreeDataAfterGenTexture(const aFreeData: Boolean);
begin
  glBitmapDefaultFreeDataAfterGenTextures := aFreeData;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultMipmap(const aValue: TglBitmapMipMap);
begin
  glBitmapDefaultMipmap := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultFormat(const aFormat: TglBitmapFormat);
begin
  glBitmapDefaultFormat := aFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultFilter(const aMin, aMag: Integer);
begin
  glBitmapDefaultFilterMin := aMin;
  glBitmapDefaultFilterMag := aMag;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultWrap(const S: Cardinal = GL_CLAMP_TO_EDGE; const T: Cardinal = GL_CLAMP_TO_EDGE; const R: Cardinal = GL_CLAMP_TO_EDGE);
begin
  glBitmapDefaultWrapS := S;
  glBitmapDefaultWrapT := T;
  glBitmapDefaultWrapR := R;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapSetDefaultSwizzle(const r: GLenum = GL_RED; g: GLenum = GL_GREEN; b: GLenum = GL_BLUE; a: GLenum = GL_ALPHA);
begin
  glDefaultSwizzle[0] := r;
  glDefaultSwizzle[1] := g;
  glDefaultSwizzle[2] := b;
  glDefaultSwizzle[3] := a;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapGetDefaultDeleteTextureOnFree: Boolean;
begin
  result := glBitmapDefaultDeleteTextureOnFree;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapGetDefaultFreeDataAfterGenTexture: Boolean;
begin
  result := glBitmapDefaultFreeDataAfterGenTextures;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapGetDefaultMipmap: TglBitmapMipMap;
begin
  result := glBitmapDefaultMipmap;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmapGetDefaultFormat: TglBitmapFormat;
begin
  result := glBitmapDefaultFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapGetDefaultFilter(var aMin, aMag: GLenum);
begin
  aMin := glBitmapDefaultFilterMin;
  aMag := glBitmapDefaultFilterMag;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapGetDefaultTextureWrap(var S, T, R: GLenum);
begin
  S := glBitmapDefaultWrapS;
  T := glBitmapDefaultWrapT;
  R := glBitmapDefaultWrapR;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapGetDefaultSwizzle(var r, g, b, a: GLenum);
begin
  r := glDefaultSwizzle[0];
  g := glDefaultSwizzle[1];
  b := glDefaultSwizzle[2];
  a := glDefaultSwizzle[3];
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmapFormatDescriptor///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetRedMask: QWord;
begin
  result := fRange.r shl fShift.r;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetGreenMask: QWord;
begin
  result := fRange.g shl fShift.g;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetBlueMask: QWord;
begin
  result := fRange.b shl fShift.b;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetAlphaMask: QWord;
begin
  result := fRange.a shl fShift.a;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetIsCompressed: Boolean;
begin
  result := fIsCompressed;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetHasAlpha: Boolean;
begin
  result := (fRange.a > 0);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetglFormat: GLenum;
begin
  result := fglFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetglInternalFormat: GLenum;
begin
  result := fglInternalFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetglDataFormat: GLenum;
begin
  result := fglDataFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetComponents: Integer;
var
  i: Integer;
begin
  result := 0;
  for i := 0 to 3 do
    if (fRange.arr[i] > 0) then
      inc(result);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetSize(const aSize: TglBitmapPixelPosition): Integer;
var
  w, h: Integer;
begin
  if (ffX in aSize.Fields) or (ffY in aSize.Fields) then begin
    w := Max(1, aSize.X);
    h := Max(1, aSize.Y);
    result := GetSize(w, h);
  end else
    result := 0;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.GetSize(const aWidth, aHeight: Integer): Integer;
begin
  result := 0;
  if (aWidth <= 0) or (aHeight <= 0) then
    exit;
  result := Ceil(aWidth * aHeight * fPixelSize);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.CreateMappingData: Pointer;
begin
  result := nil;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TFormatDescriptor.FreeMappingData(var aMappingData: Pointer);
begin
  //DUMMY
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.IsEmpty: Boolean;
begin
  result := (fFormat = tfEmpty);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TFormatDescriptor.MaskMatch(const aRedMask, aGreenMask, aBlueMask, aAlphaMask: QWord): Boolean;
begin
  result := false;
  if (aRedMask = 0) and (aGreenMask = 0) and (aBlueMask = 0) and (aAlphaMask = 0) then
    raise EglBitmap.Create('FormatCheckFormat - All Masks are 0');
  if (aRedMask   <> RedMask) then
    exit;
  if (aGreenMask <> GreenMask) then
    exit;
  if (aBlueMask  <> BlueMask) then
    exit;
  if (aAlphaMask <> AlphaMask) then
    exit;
  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TFormatDescriptor.PreparePixel(out aPixel: TglBitmapPixelData);
begin
  FillChar(aPixel{%H-}, SizeOf(aPixel), 0);
  aPixel.Data   := fRange;
  aPixel.Range  := fRange;
  aPixel.Format := fFormat;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TFormatDescriptor.Create;
begin
  inherited Create;

  fFormat       := tfEmpty;
  fWithAlpha    := tfEmpty;
  fWithoutAlpha := tfEmpty;
  fRGBInverted  := tfEmpty;
  fUncompressed := tfEmpty;
  fPixelSize    := 0.0;
  fIsCompressed := false;

  fglFormat         := 0;
  fglInternalFormat := 0;
  fglDataFormat     := 0;

  FillChar(fRange, 0, SizeOf(fRange));
  FillChar(fShift, 0, SizeOf(fShift));
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdAlpha_UB1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdAlpha_UB1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  aData^ := aPixel.Data.a;
  inc(aData);
end;

procedure TfdAlpha_UB1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := 0;
  aPixel.Data.g := 0;
  aPixel.Data.b := 0;
  aPixel.Data.a := aData^;
  inc(aData);
end;

constructor TfdAlpha_UB1.Create;
begin
  inherited Create;
  fPixelSize        := 1.0;
  fRange.a          := $FF;
  fglFormat         := GL_ALPHA;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdLuminance_UB1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdLuminance_UB1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  aData^ := LuminanceWeight(aPixel);
  inc(aData);
end;

procedure TfdLuminance_UB1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := aData^;
  aPixel.Data.g := aData^;
  aPixel.Data.b := aData^;
  aPixel.Data.a := 0;
  inc(aData);
end;

constructor TfdLuminance_UB1.Create;
begin
  inherited Create;
  fPixelSize        := 1.0;
  fRange.r          := $FF;
  fRange.g          := $FF;
  fRange.b          := $FF;
  fglFormat         := GL_LUMINANCE;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdUniversal_UB1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdUniversal_UB1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
var
  i: Integer;
begin
  aData^ := 0;
  for i := 0 to 3 do
    if (fRange.arr[i] > 0) then
      aData^ := aData^ or ((aPixel.Data.arr[i] and fRange.arr[i]) shl fShift.arr[i]);
  inc(aData);
end;

procedure TfdUniversal_UB1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
var
  i: Integer;
begin
  for i := 0 to 3 do
    aPixel.Data.arr[i] := (aData^ shr fShift.arr[i]) and fRange.arr[i];
  inc(aData);
end;

constructor TfdUniversal_UB1.Create;
begin
  inherited Create;
  fPixelSize := 1.0;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdLuminanceAlpha_UB2///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdLuminanceAlpha_UB2.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  aData^ := aPixel.Data.a;
  inc(aData);
end;

procedure TfdLuminanceAlpha_UB2.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := aData^;
  inc(aData);
end;

constructor TfdLuminanceAlpha_UB2.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fRange.a          := $FF;
  fShift.a          :=   8;
  fglFormat         := GL_LUMINANCE_ALPHA;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdRGB_UB3//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdRGB_UB3.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  aData^ := aPixel.Data.r;
  inc(aData);
  aData^ := aPixel.Data.g;
  inc(aData);
  aData^ := aPixel.Data.b;
  inc(aData);
end;

procedure TfdRGB_UB3.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := aData^;
  inc(aData);
  aPixel.Data.g := aData^;
  inc(aData);
  aPixel.Data.b := aData^;
  inc(aData);
  aPixel.Data.a := 0;
end;

constructor TfdRGB_UB3.Create;
begin
  inherited Create;
  fPixelSize        := 3.0;
  fRange.r          := $FF;
  fRange.g          := $FF;
  fRange.b          := $FF;
  fShift.r          :=   0;
  fShift.g          :=   8;
  fShift.b          :=  16;
  fglFormat         := GL_RGB;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdBGR_UB3//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdBGR_UB3.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  aData^ := aPixel.Data.b;
  inc(aData);
  aData^ := aPixel.Data.g;
  inc(aData);
  aData^ := aPixel.Data.r;
  inc(aData);
end;

procedure TfdBGR_UB3.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.b := aData^;
  inc(aData);
  aPixel.Data.g := aData^;
  inc(aData);
  aPixel.Data.r := aData^;
  inc(aData);
  aPixel.Data.a := 0;
end;

constructor TfdBGR_UB3.Create;
begin
  fPixelSize        := 3.0;
  fRange.r          := $FF;
  fRange.g          := $FF;
  fRange.b          := $FF;
  fShift.r          :=  16;
  fShift.g          :=   8;
  fShift.b          :=   0;
  fglFormat         := GL_BGR;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TdfRGBA_UB4/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdRGBA_UB4.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  aData^ := aPixel.Data.a;
  inc(aData);
end;

procedure TfdRGBA_UB4.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := aData^;
  inc(aData);
end;

constructor TfdRGBA_UB4.Create;
begin
  inherited Create;
  fPixelSize        := 4.0;
  fRange.a          := $FF;
  fShift.a          :=  24;
  fglFormat         := GL_RGBA;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdBGRA_UB4/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdBGRA_UB4.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  aData^ := aPixel.Data.a;
  inc(aData);
end;

procedure TfdBGRA_UB4.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := aData^;
  inc(aData);
end;

constructor TfdBGRA_UB4.Create;
begin
  inherited Create;
  fPixelSize        := 4.0;
  fRange.a          := $FF;
  fShift.a          :=  24;
  fglFormat         := GL_BGRA;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdAlpha_US1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdAlpha_US1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PWord(aData)^ := aPixel.Data.a;
  inc(aData, 2);
end;

procedure TfdAlpha_US1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := 0;
  aPixel.Data.g := 0;
  aPixel.Data.b := 0;
  aPixel.Data.a := PWord(aData)^;
  inc(aData, 2);
end;

constructor TfdAlpha_US1.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fRange.a          := $FFFF;
  fglFormat         := GL_ALPHA;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdLuminance_US1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdLuminance_US1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PWord(aData)^ := LuminanceWeight(aPixel);
  inc(aData, 2);
end;

procedure TfdLuminance_US1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := PWord(aData)^;
  aPixel.Data.g := PWord(aData)^;
  aPixel.Data.b := PWord(aData)^;
  aPixel.Data.a := 0;
  inc(aData, 2);
end;

constructor TfdLuminance_US1.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fRange.r          := $FFFF;
  fRange.g          := $FFFF;
  fRange.b          := $FFFF;
  fglFormat         := GL_LUMINANCE;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdUniversal_US1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdUniversal_US1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
var
  i: Integer;
begin
  PWord(aData)^ := 0;
  for i := 0 to 3 do
    if (fRange.arr[i] > 0) then
      PWord(aData)^ := PWord(aData)^ or ((aPixel.Data.arr[i] and fRange.arr[i]) shl fShift.arr[i]);
  inc(aData, 2);
end;

procedure TfdUniversal_US1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
var
  i: Integer;
begin
  for i := 0 to 3 do
    aPixel.Data.arr[i] := (PWord(aData)^ shr fShift.arr[i]) and fRange.arr[i];
  inc(aData, 2);
end;

constructor TfdUniversal_US1.Create;
begin
  inherited Create;
  fPixelSize := 2.0;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdDepth_US1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdDepth_US1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PWord(aData)^ := DepthWeight(aPixel);
  inc(aData, 2);
end;

procedure TfdDepth_US1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := PWord(aData)^;
  aPixel.Data.g := PWord(aData)^;
  aPixel.Data.b := PWord(aData)^;
  aPixel.Data.a := 0;
  inc(aData, 2);
end;

constructor TfdDepth_US1.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fRange.r          := $FFFF;
  fRange.g          := $FFFF;
  fRange.b          := $FFFF;
  fglFormat         := GL_DEPTH_COMPONENT;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdLuminanceAlpha_US2///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdLuminanceAlpha_US2.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  PWord(aData)^ := aPixel.Data.a;
  inc(aData, 2);
end;

procedure TfdLuminanceAlpha_US2.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := PWord(aData)^;
  inc(aData, 2);
end;

constructor TfdLuminanceAlpha_US2.Create;
begin
  inherited Create;
  fPixelSize        :=   4.0;
  fRange.a          := $FFFF;
  fShift.a          :=    16;
  fglFormat         := GL_LUMINANCE_ALPHA;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdRGB_US3//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdRGB_US3.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PWord(aData)^ := aPixel.Data.r;
  inc(aData, 2);
  PWord(aData)^ := aPixel.Data.g;
  inc(aData, 2);
  PWord(aData)^ := aPixel.Data.b;
  inc(aData, 2);
end;

procedure TfdRGB_US3.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.g := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.b := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.a := 0;
end;

constructor TfdRGB_US3.Create;
begin
  inherited Create;
  fPixelSize        :=   6.0;
  fRange.r          := $FFFF;
  fRange.g          := $FFFF;
  fRange.b          := $FFFF;
  fShift.r          :=     0;
  fShift.g          :=    16;
  fShift.b          :=    32;
  fglFormat         := GL_RGB;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdBGR_US3//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdBGR_US3.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PWord(aData)^ := aPixel.Data.b;
  inc(aData, 2);
  PWord(aData)^ := aPixel.Data.g;
  inc(aData, 2);
  PWord(aData)^ := aPixel.Data.r;
  inc(aData, 2);
end;

procedure TfdBGR_US3.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.b := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.g := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.r := PWord(aData)^;
  inc(aData, 2);
  aPixel.Data.a := 0;
end;

constructor TfdBGR_US3.Create;
begin
  inherited Create;
  fPixelSize        :=   6.0;
  fRange.r          := $FFFF;
  fRange.g          := $FFFF;
  fRange.b          := $FFFF;
  fShift.r          :=    32;
  fShift.g          :=    16;
  fShift.b          :=     0;
  fglFormat         := GL_BGR;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdRGBA_US4/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdRGBA_US4.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  PWord(aData)^ := aPixel.Data.a;
  inc(aData, 2);
end;

procedure TfdRGBA_US4.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := PWord(aData)^;
  inc(aData, 2);
end;

constructor TfdRGBA_US4.Create;
begin
  inherited Create;
  fPixelSize        :=   8.0;
  fRange.a          := $FFFF;
  fShift.a          :=    48;
  fglFormat         := GL_RGBA;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdBGRA_US4/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdBGRA_US4.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  inherited Map(aPixel, aData, aMapData);
  PWord(aData)^ := aPixel.Data.a;
  inc(aData, 2);
end;

procedure TfdBGRA_US4.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  inherited Unmap(aData, aPixel, aMapData);
  aPixel.Data.a := PWord(aData)^;
  inc(aData, 2);
end;

constructor TfdBGRA_US4.Create;
begin
  inherited Create;
  fPixelSize        :=   8.0;
  fRange.a          := $FFFF;
  fShift.a          :=    48;
  fglFormat         := GL_BGRA;
  fglDataFormat     := GL_UNSIGNED_SHORT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdUniversal_UI1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdUniversal_UI1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
var
  i: Integer;
begin
  PCardinal(aData)^ := 0;
  for i := 0 to 3 do
    if (fRange.arr[i] > 0) then
      PCardinal(aData)^ := PCardinal(aData)^ or ((aPixel.Data.arr[i] and fRange.arr[i]) shl fShift.arr[i]);
  inc(aData, 4);
end;

procedure TfdUniversal_UI1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
var
  i: Integer;
begin
  for i := 0 to 3 do
    aPixel.Data.arr[i] := (PCardinal(aData)^ shr fShift.arr[i]) and fRange.arr[i];
  inc(aData, 2);
end;

constructor TfdUniversal_UI1.Create;
begin
  inherited Create;
  fPixelSize := 4.0;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdDepth_UI1////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdDepth_UI1.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  PCardinal(aData)^ := DepthWeight(aPixel);
  inc(aData, 4);
end;

procedure TfdDepth_UI1.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  aPixel.Data.r := PCardinal(aData)^;
  aPixel.Data.g := PCardinal(aData)^;
  aPixel.Data.b := PCardinal(aData)^;
  aPixel.Data.a := 0;
  inc(aData, 4);
end;

constructor TfdDepth_UI1.Create;
begin
  inherited Create;
  fPixelSize        := 4.0;
  fRange.r          := $FFFFFFFF;
  fRange.g          := $FFFFFFFF;
  fRange.b          := $FFFFFFFF;
  fglFormat         := GL_DEPTH_COMPONENT;
  fglDataFormat     := GL_UNSIGNED_INT;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TfdAlpha4.Create;
begin
  inherited Create;
  fFormat           := tfAlpha4;
  fWithAlpha        := tfAlpha4;
  fglInternalFormat := GL_ALPHA4;
end;

constructor TfdAlpha8.Create;
begin
  inherited Create;
  fFormat           := tfAlpha8;
  fWithAlpha        := tfAlpha8;
  fglInternalFormat := GL_ALPHA8;
end;

constructor TfdAlpha12.Create;
begin
  inherited Create;
  fFormat           := tfAlpha12;
  fWithAlpha        := tfAlpha12;
  fglInternalFormat := GL_ALPHA12;
end;

constructor TfdAlpha16.Create;
begin
  inherited Create;
  fFormat           := tfAlpha16;
  fWithAlpha        := tfAlpha16;
  fglInternalFormat := GL_ALPHA16;
end;

constructor TfdLuminance4.Create;
begin
  inherited Create;
  fFormat           := tfLuminance4;
  fWithAlpha        := tfLuminance4Alpha4;
  fWithoutAlpha     := tfLuminance4;
  fglInternalFormat := GL_LUMINANCE4;
end;

constructor TfdLuminance8.Create;
begin
  inherited Create;
  fFormat           := tfLuminance8;
  fWithAlpha        := tfLuminance8Alpha8;
  fWithoutAlpha     := tfLuminance8;
  fglInternalFormat := GL_LUMINANCE8;
end;

constructor TfdLuminance12.Create;
begin
  inherited Create;
  fFormat           := tfLuminance12;
  fWithAlpha        := tfLuminance12Alpha12;
  fWithoutAlpha     := tfLuminance12;
  fglInternalFormat := GL_LUMINANCE12;
end;

constructor TfdLuminance16.Create;
begin
  inherited Create;
  fFormat           := tfLuminance16;
  fWithAlpha        := tfLuminance16Alpha16;
  fWithoutAlpha     := tfLuminance16;
  fglInternalFormat := GL_LUMINANCE16;
end;

constructor TfdLuminance4Alpha4.Create;
begin
  inherited Create;
  fFormat           := tfLuminance4Alpha4;
  fWithAlpha        := tfLuminance4Alpha4;
  fWithoutAlpha     := tfLuminance4;
  fglInternalFormat := GL_LUMINANCE4_ALPHA4;
end;

constructor TfdLuminance6Alpha2.Create;
begin
  inherited Create;
  fFormat           := tfLuminance6Alpha2;
  fWithAlpha        := tfLuminance6Alpha2;
  fWithoutAlpha     := tfLuminance8;
  fglInternalFormat := GL_LUMINANCE6_ALPHA2;
end;

constructor TfdLuminance8Alpha8.Create;
begin
  inherited Create;
  fFormat           := tfLuminance8Alpha8;
  fWithAlpha        := tfLuminance8Alpha8;
  fWithoutAlpha     := tfLuminance8;
  fglInternalFormat := GL_LUMINANCE8_ALPHA8;
end;

constructor TfdLuminance12Alpha4.Create;
begin
  inherited Create;
  fFormat           := tfLuminance12Alpha4;
  fWithAlpha        := tfLuminance12Alpha4;
  fWithoutAlpha     := tfLuminance12;
  fglInternalFormat := GL_LUMINANCE12_ALPHA4;
end;

constructor TfdLuminance12Alpha12.Create;
begin
  inherited Create;
  fFormat           := tfLuminance12Alpha12;
  fWithAlpha        := tfLuminance12Alpha12;
  fWithoutAlpha     := tfLuminance12;
  fglInternalFormat := GL_LUMINANCE12_ALPHA12;
end;

constructor TfdLuminance16Alpha16.Create;
begin
  inherited Create;
  fFormat           := tfLuminance16Alpha16;
  fWithAlpha        := tfLuminance16Alpha16;
  fWithoutAlpha     := tfLuminance16;
  fglInternalFormat := GL_LUMINANCE16_ALPHA16;
end;

constructor TfdR3G3B2.Create;
begin
  inherited Create;
  fFormat           := tfR3G3B2;
  fWithAlpha        := tfRGBA2;
  fWithoutAlpha     := tfR3G3B2;
  fRange.r          := $7;
  fRange.g          := $7;
  fRange.b          := $3;
  fShift.r          :=  0;
  fShift.g          :=  3;
  fShift.b          :=  6;
  fglFormat         := GL_RGB;
  fglInternalFormat := GL_R3_G3_B2;
  fglDataFormat     := GL_UNSIGNED_BYTE_2_3_3_REV;
end;

constructor TfdRGB4.Create;
begin
  inherited Create;
  fFormat           := tfRGB4;
  fWithAlpha        := tfRGBA4;
  fWithoutAlpha     := tfRGB4;
  fRGBInverted      := tfBGR4;
  fRange.r          := $F;
  fRange.g          := $F;
  fRange.b          := $F;
  fShift.r          :=  0;
  fShift.g          :=  4;
  fShift.b          :=  8;
  fglFormat         := GL_RGBA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB4;
  fglDataFormat     := GL_UNSIGNED_SHORT_4_4_4_4_REV;
end;

constructor TfdR5G6B5.Create;
begin
  inherited Create;
  fFormat           := tfR5G6B5;
  fWithAlpha        := tfRGBA4;
  fWithoutAlpha     := tfR5G6B5;
  fRGBInverted      := tfB5G6R5;
  fRange.r          := $1F;
  fRange.g          := $3F;
  fRange.b          := $1F;
  fShift.r          :=   0;
  fShift.g          :=   5;
  fShift.b          :=  11;
  fglFormat         := GL_RGB;
  fglInternalFormat := GL_RGB565;
  fglDataFormat     := GL_UNSIGNED_SHORT_5_6_5_REV;
end;

constructor TfdRGB5.Create;
begin
  inherited Create;
  fFormat           := tfRGB5;
  fWithAlpha        := tfRGB5A1;
  fWithoutAlpha     := tfRGB5;
  fRGBInverted      := tfBGR5;
  fRange.r          := $1F;
  fRange.g          := $1F;
  fRange.b          := $1F;
  fShift.r          :=   0;
  fShift.g          :=   5;
  fShift.b          :=  10;
  fglFormat         := GL_RGBA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB5;
  fglDataFormat     := GL_UNSIGNED_SHORT_1_5_5_5_REV;
end;

constructor TfdRGB8.Create;
begin
  inherited Create;
  fFormat           := tfRGB8;
  fWithAlpha        := tfRGBA8;
  fWithoutAlpha     := tfRGB8;
  fRGBInverted      := tfBGR8;
  fglInternalFormat := GL_RGB8;
end;

constructor TfdRGB10.Create;
begin
  inherited Create;
  fFormat           := tfRGB10;
  fWithAlpha        := tfRGB10A2;
  fWithoutAlpha     := tfRGB10;
  fRGBInverted      := tfBGR10;
  fRange.r          := $3FF;
  fRange.g          := $3FF;
  fRange.b          := $3FF;
  fShift.r          :=    0;
  fShift.g          :=   10;
  fShift.b          :=   20;
  fglFormat         := GL_RGBA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB10;
  fglDataFormat     := GL_UNSIGNED_INT_2_10_10_10_REV;
end;

constructor TfdRGB12.Create;
begin
  inherited Create;
  fFormat           := tfRGB12;
  fWithAlpha        := tfRGBA12;
  fWithoutAlpha     := tfRGB12;
  fRGBInverted      := tfBGR12;
  fglInternalFormat := GL_RGB12;
end;

constructor TfdRGB16.Create;
begin
  inherited Create;
  fFormat           := tfRGB16;
  fWithAlpha        := tfRGBA16;
  fWithoutAlpha     := tfRGB16;
  fRGBInverted      := tfBGR16;
  fglInternalFormat := GL_RGB16;
end;

constructor TfdRGBA2.Create;
begin
  inherited Create;
  fFormat           := tfRGBA2;
  fWithAlpha        := tfRGBA2;
  fWithoutAlpha     := tfR3G3B2;
  fRGBInverted      := tfBGRA2;
  fglInternalFormat := GL_RGBA2;
end;

constructor TfdRGBA4.Create;
begin
  inherited Create;
  fFormat           := tfRGBA4;
  fWithAlpha        := tfRGBA4;
  fWithoutAlpha     := tfRGB4;
  fRGBInverted      := tfBGRA4;
  fRange.r          := $F;
  fRange.g          := $F;
  fRange.b          := $F;
  fRange.a          := $F;
  fShift.r          :=  0;
  fShift.g          :=  4;
  fShift.b          :=  8;
  fShift.a          := 12;
  fglFormat         := GL_RGBA;
  fglInternalFormat := GL_RGBA4;
  fglDataFormat     := GL_UNSIGNED_SHORT_4_4_4_4_REV;
end;

constructor TfdRGB5A1.Create;
begin
  inherited Create;
  fFormat           := tfRGB5A1;
  fWithAlpha        := tfRGB5A1;
  fWithoutAlpha     := tfRGB5;
  fRGBInverted      := tfBGR5A1;
  fRange.r          := $1F;
  fRange.g          := $1F;
  fRange.b          := $1F;
  fRange.a          := $01;
  fShift.r          :=   0;
  fShift.g          :=   5;
  fShift.b          :=  10;
  fShift.a          :=  15;
  fglFormat         := GL_RGBA;
  fglInternalFormat := GL_RGB5_A1;
  fglDataFormat     := GL_UNSIGNED_SHORT_1_5_5_5_REV;
end;

constructor TfdRGBA8.Create;
begin
  inherited Create;
  fFormat           := tfRGBA8;
  fWithAlpha        := tfRGBA8;
  fWithoutAlpha     := tfRGB8;
  fRGBInverted      := tfBGRA8;
  fglInternalFormat := GL_RGBA8;
end;

constructor TfdRGB10A2.Create;
begin
  inherited Create;
  fFormat           := tfRGB10A2;
  fWithAlpha        := tfRGB10A2;
  fWithoutAlpha     := tfRGB10;
  fRGBInverted      := tfBGR10A2;
  fRange.r          := $3FF;
  fRange.g          := $3FF;
  fRange.b          := $3FF;
  fRange.a          := $003;
  fShift.r          :=    0;
  fShift.g          :=   10;
  fShift.b          :=   20;
  fShift.a          :=   30;
  fglFormat         := GL_RGBA;
  fglInternalFormat := GL_RGB10_A2;
  fglDataFormat     := GL_UNSIGNED_INT_2_10_10_10_REV;
end;

constructor TfdRGBA12.Create;
begin
  inherited Create;
  fFormat           := tfRGBA12;
  fWithAlpha        := tfRGBA12;
  fWithoutAlpha     := tfRGB12;
  fRGBInverted      := tfBGRA12;
  fglInternalFormat := GL_RGBA12;
end;

constructor TfdRGBA16.Create;
begin
  inherited Create;
  fFormat           := tfRGBA16;
  fWithAlpha        := tfRGBA16;
  fWithoutAlpha     := tfRGB16;
  fRGBInverted      := tfBGRA16;
  fglInternalFormat := GL_RGBA16;
end;

constructor TfdBGR4.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fFormat           := tfBGR4;
  fWithAlpha        := tfBGRA4;
  fWithoutAlpha     := tfBGR4;
  fRGBInverted      := tfRGB4;
  fRange.r          := $F;
  fRange.g          := $F;
  fRange.b          := $F;
  fRange.a          := $0;
  fShift.r          :=  8;
  fShift.g          :=  4;
  fShift.b          :=  0;
  fShift.a          :=  0;
  fglFormat         := GL_BGRA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB4;
  fglDataFormat     := GL_UNSIGNED_SHORT_4_4_4_4_REV;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TfdB5G6R5.Create;
begin
  inherited Create;
  fFormat           := tfB5G6R5;
  fWithAlpha        := tfBGRA4;
  fWithoutAlpha     := tfB5G6R5;
  fRGBInverted      := tfR5G6B5;
  fRange.r          := $1F;
  fRange.g          := $3F;
  fRange.b          := $1F;
  fShift.r          :=  11;
  fShift.g          :=   5;
  fShift.b          :=   0;
  fglFormat         := GL_RGB;  //B5G6R5 is only possible as R5G6B5 -> use reverted dataformat
  fglInternalFormat := GL_RGB8;
  fglDataFormat     := GL_UNSIGNED_SHORT_5_6_5;
end;

constructor TfdBGR5.Create;
begin
  inherited Create;
  fPixelSize        := 2.0;
  fFormat           := tfBGR5;
  fWithAlpha        := tfBGR5A1;
  fWithoutAlpha     := tfBGR5;
  fRGBInverted      := tfRGB5;
  fRange.r          := $1F;
  fRange.g          := $1F;
  fRange.b          := $1F;
  fRange.a          := $00;
  fShift.r          :=  10;
  fShift.g          :=   5;
  fShift.b          :=   0;
  fShift.a          :=   0;
  fglFormat         := GL_BGRA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB5;
  fglDataFormat     := GL_UNSIGNED_SHORT_1_5_5_5_REV;
end;

constructor TfdBGR8.Create;
begin
  inherited Create;
  fFormat           := tfBGR8;
  fWithAlpha        := tfBGRA8;
  fWithoutAlpha     := tfBGR8;
  fRGBInverted      := tfRGB8;
  fglInternalFormat := GL_RGB8;
end;

constructor TfdBGR10.Create;
begin
  inherited Create;
  fFormat           := tfBGR10;
  fWithAlpha        := tfBGR10A2;
  fWithoutAlpha     := tfBGR10;
  fRGBInverted      := tfRGB10;
  fRange.r          := $3FF;
  fRange.g          := $3FF;
  fRange.b          := $3FF;
  fRange.a          := $000;
  fShift.r          :=   20;
  fShift.g          :=   10;
  fShift.b          :=    0;
  fShift.a          :=    0;
  fglFormat         := GL_BGRA; //GL_INVALID_OPERATION if not GL_BGRA or GL_RGBA
  fglInternalFormat := GL_RGB10;
  fglDataFormat     := GL_UNSIGNED_INT_2_10_10_10_REV;
end;

constructor TfdBGR12.Create;
begin
  inherited Create;
  fFormat           := tfBGR12;
  fWithAlpha        := tfBGRA12;
  fWithoutAlpha     := tfBGR12;
  fRGBInverted      := tfRGB12;
  fglInternalFormat := GL_RGB12;
end;

constructor TfdBGR16.Create;
begin
  inherited Create;
  fFormat           := tfBGR16;
  fWithAlpha        := tfBGRA16;
  fWithoutAlpha     := tfBGR16;
  fRGBInverted      := tfRGB16;
  fglInternalFormat := GL_RGB16;
end;

constructor TfdBGRA2.Create;
begin
  inherited Create;
  fFormat           := tfBGRA2;
  fWithAlpha        := tfBGRA4;
  fWithoutAlpha     := tfBGR4;
  fRGBInverted      := tfRGBA2;
  fglInternalFormat := GL_RGBA2;
end;

constructor TfdBGRA4.Create;
begin
  inherited Create;
  fFormat           := tfBGRA4;
  fWithAlpha        := tfBGRA4;
  fWithoutAlpha     := tfBGR4;
  fRGBInverted      := tfRGBA4;
  fRange.r          := $F;
  fRange.g          := $F;
  fRange.b          := $F;
  fRange.a          := $F;
  fShift.r          :=  8;
  fShift.g          :=  4;
  fShift.b          :=  0;
  fShift.a          := 12;
  fglFormat         := GL_BGRA;
  fglInternalFormat := GL_RGBA4;
  fglDataFormat     := GL_UNSIGNED_SHORT_4_4_4_4_REV;
end;

constructor TfdBGR5A1.Create;
begin
  inherited Create;
  fFormat           := tfBGR5A1;
  fWithAlpha        := tfBGR5A1;
  fWithoutAlpha     := tfBGR5;
  fRGBInverted      := tfRGB5A1;
  fRange.r          := $1F;
  fRange.g          := $1F;
  fRange.b          := $1F;
  fRange.a          := $01;
  fShift.r          :=  10;
  fShift.g          :=   5;
  fShift.b          :=   0;
  fShift.a          :=  15;
  fglFormat         := GL_BGRA;
  fglInternalFormat := GL_RGB5_A1;
  fglDataFormat     := GL_UNSIGNED_SHORT_1_5_5_5_REV;
end;

constructor TfdBGRA8.Create;
begin
  inherited Create;
  fFormat           := tfBGRA8;
  fWithAlpha        := tfBGRA8;
  fWithoutAlpha     := tfBGR8;
  fRGBInverted      := tfRGBA8;
  fglInternalFormat := GL_RGBA8;
end;

constructor TfdBGR10A2.Create;
begin
  inherited Create;
  fFormat           := tfBGR10A2;
  fWithAlpha        := tfBGR10A2;
  fWithoutAlpha     := tfBGR10;
  fRGBInverted      := tfRGB10A2;
  fRange.r          := $3FF;
  fRange.g          := $3FF;
  fRange.b          := $3FF;
  fRange.a          := $003;
  fShift.r          :=   20;
  fShift.g          :=   10;
  fShift.b          :=    0;
  fShift.a          :=   30;
  fglFormat         := GL_BGRA;
  fglInternalFormat := GL_RGB10_A2;
  fglDataFormat     := GL_UNSIGNED_INT_2_10_10_10_REV;
end;

constructor TfdBGRA12.Create;
begin
  inherited Create;
  fFormat           := tfBGRA12;
  fWithAlpha        := tfBGRA12;
  fWithoutAlpha     := tfBGR12;
  fRGBInverted      := tfRGBA12;
  fglInternalFormat := GL_RGBA12;
end;

constructor TfdBGRA16.Create;
begin
  inherited Create;
  fFormat           := tfBGRA16;
  fWithAlpha        := tfBGRA16;
  fWithoutAlpha     := tfBGR16;
  fRGBInverted      := tfRGBA16;
  fglInternalFormat := GL_RGBA16;
end;

constructor TfdDepth16.Create;
begin
  inherited Create;
  fFormat           := tfDepth16;
  fWithAlpha        := tfEmpty;
  fWithoutAlpha     := tfDepth16;
  fglInternalFormat := GL_DEPTH_COMPONENT16;
end;

constructor TfdDepth24.Create;
begin
  inherited Create;
  fFormat           := tfDepth24;
  fWithAlpha        := tfEmpty;
  fWithoutAlpha     := tfDepth24;
  fglInternalFormat := GL_DEPTH_COMPONENT24;
end;

constructor TfdDepth32.Create;
begin
  inherited Create;
  fFormat           := tfDepth32;
  fWithAlpha        := tfEmpty;
  fWithoutAlpha     := tfDepth32;
  fglInternalFormat := GL_DEPTH_COMPONENT32;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdS3tcDtx1RGBA/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdS3tcDtx1RGBA.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

procedure TfdS3tcDtx1RGBA.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

constructor TfdS3tcDtx1RGBA.Create;
begin
  inherited Create;
  fFormat           := tfS3tcDtx1RGBA;
  fWithAlpha        := tfS3tcDtx1RGBA;
  fUncompressed     := tfRGB5A1;
  fPixelSize        := 0.5;
  fIsCompressed     := true;
  fglFormat         := GL_COMPRESSED_RGBA;
  fglInternalFormat := GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdS3tcDtx3RGBA/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdS3tcDtx3RGBA.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

procedure TfdS3tcDtx3RGBA.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

constructor TfdS3tcDtx3RGBA.Create;
begin
  inherited Create;
  fFormat           := tfS3tcDtx3RGBA;
  fWithAlpha        := tfS3tcDtx3RGBA;
  fUncompressed     := tfRGBA8;
  fPixelSize        := 1.0;
  fIsCompressed     := true;
  fglFormat         := GL_COMPRESSED_RGBA;
  fglInternalFormat := GL_COMPRESSED_RGBA_S3TC_DXT3_EXT;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TfdS3tcDtx5RGBA/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TfdS3tcDtx5RGBA.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

procedure TfdS3tcDtx5RGBA.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
begin
  raise EglBitmap.Create('mapping for compressed formats is not supported');
end;

constructor TfdS3tcDtx5RGBA.Create;
begin
  inherited Create;
  fFormat           := tfS3tcDtx3RGBA;
  fWithAlpha        := tfS3tcDtx3RGBA;
  fUncompressed     := tfRGBA8;
  fPixelSize        := 1.0;
  fIsCompressed     := true;
  fglFormat         := GL_COMPRESSED_RGBA;
  fglInternalFormat := GL_COMPRESSED_RGBA_S3TC_DXT5_EXT;
  fglDataFormat     := GL_UNSIGNED_BYTE;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TFormatDescriptor///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class procedure TFormatDescriptor.Init;
begin
  if not Assigned(FormatDescriptorCS) then
    FormatDescriptorCS := TCriticalSection.Create;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class function TFormatDescriptor.Get(const aFormat: TglBitmapFormat): TFormatDescriptor;
begin
  FormatDescriptorCS.Enter;
  try
    result := FormatDescriptors[aFormat];
    if not Assigned(result) then begin
      result := FORMAT_DESCRIPTOR_CLASSES[aFormat].Create;
      FormatDescriptors[aFormat] := result;
    end;
  finally
    FormatDescriptorCS.Leave;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class function TFormatDescriptor.GetWithAlpha(const aFormat: TglBitmapFormat): TFormatDescriptor;
begin
  result := Get(Get(aFormat).WithAlpha);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class procedure TFormatDescriptor.Clear;
var
  f: TglBitmapFormat;
begin
  FormatDescriptorCS.Enter;
  try
    for f := low(FormatDescriptors) to high(FormatDescriptors) do
      FreeAndNil(FormatDescriptors[f]);
  finally
    FormatDescriptorCS.Leave;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
class procedure TFormatDescriptor.Finalize;
begin
  Clear;
  FreeAndNil(FormatDescriptorCS);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TBitfieldFormat/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.SetRedMask(const aValue: QWord);
begin
  Update(aValue, fRange.r, fShift.r);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.SetGreenMask(const aValue: QWord);
begin
  Update(aValue, fRange.g, fShift.g);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.SetBlueMask(const aValue: QWord);
begin
  Update(aValue, fRange.b, fShift.b);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.SetAlphaMask(const aValue: QWord);
begin
  Update(aValue, fRange.a, fShift.a);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.Update(aMask: QWord; out aRange: Cardinal; out
  aShift: Byte);
begin
  aShift := 0;
  aRange := 0;
  if (aMask = 0) then
    exit;
  while (aMask > 0) and ((aMask and 1) = 0) do begin
    inc(aShift);
    aMask := aMask shr 1;
  end;
  aRange := 1;
  while (aMask > 0) do begin
    aRange := aRange shl 1;
    aMask  := aMask  shr 1;
  end;
  dec(aRange);

  fPixelSize := Round(GetTopMostBit(RedMask or GreenMask or BlueMask or AlphaMask) / 8);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
var
  data: QWord;
  s: Integer;
begin
  data :=
    ((aPixel.Data.r and fRange.r) shl fShift.r) or
    ((aPixel.Data.g and fRange.g) shl fShift.g) or
    ((aPixel.Data.b and fRange.b) shl fShift.b) or
    ((aPixel.Data.a and fRange.a) shl fShift.a);
  s := Round(fPixelSize);
  case s of
    1:           aData^  := data;
    2:     PWord(aData)^ := data;
    4: PCardinal(aData)^ := data;
    8:    PQWord(aData)^ := data;
  else
    raise EglBitmap.CreateFmt('invalid pixel size: %.1f', [fPixelSize]);
  end;
  inc(aData, s);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpBitfieldFormat.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
var
  data: QWord;
  s, i: Integer;
begin
  s := Round(fPixelSize);
  case s of
    1: data :=           aData^;
    2: data :=     PWord(aData)^;
    4: data := PCardinal(aData)^;
    8: data :=    PQWord(aData)^;
  else
    raise EglBitmap.CreateFmt('invalid pixel size: %.1f', [fPixelSize]);
  end;
  for i := 0 to 3 do
    aPixel.Data.arr[i] := (data shr fShift.arr[i]) and fRange.arr[i];
  inc(aData, s);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TColorTableFormat///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpColorTableFormat.CreateColorTable;
var
  i: Integer;
begin
  if not (Format in [tfLuminance4, tfLuminance8, tfR3G3B2]) then
    raise EglBitmap.Create(UNSUPPORTED_FORMAT);

  if (Format = tfLuminance4) then
    SetLength(fColorTable, 16)
  else
    SetLength(fColorTable, 256);

  case Format of
    tfLuminance4: begin
      for i := 0 to High(fColorTable) do begin
        fColorTable[i].r := 16 * i;
        fColorTable[i].g := 16 * i;
        fColorTable[i].b := 16 * i;
        fColorTable[i].a := 0;
      end;
    end;

    tfLuminance8: begin
      for i := 0 to High(fColorTable) do begin
        fColorTable[i].r := i;
        fColorTable[i].g := i;
        fColorTable[i].b := i;
        fColorTable[i].a := 0;
      end;
    end;

    tfR3G3B2: begin
      for i := 0 to High(fColorTable) do begin
        fColorTable[i].r := Round(((i shr Shift.r) and Range.r) / Range.r * 255);
        fColorTable[i].g := Round(((i shr Shift.g) and Range.g) / Range.g * 255);
        fColorTable[i].b := Round(((i shr Shift.b) and Range.b) / Range.b * 255);
        fColorTable[i].a := 0;
      end;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpColorTableFormat.Map(const aPixel: TglBitmapPixelData; var aData: PByte; var aMapData: Pointer);
var
  d: Byte;
begin
  if not (Format in [tfLuminance4, tfLuminance8, tfR3G3B2]) then
    raise EglBitmap.Create(UNSUPPORTED_FORMAT);

  case Format of
    tfLuminance4: begin
      if (aMapData = nil) then
        aData^ := 0;
      d := LuminanceWeight(aPixel) and Range.r;
      aData^ := aData^ or (d shl (4 - {%H-}PtrUInt(aMapData)));
      inc(PByte(aMapData), 4);
      if ({%H-}PtrUInt(aMapData) >= 8) then begin
        inc(aData);
        aMapData := nil;
      end;
    end;

    tfLuminance8: begin
      aData^ := LuminanceWeight(aPixel) and Range.r;
      inc(aData);
    end;

    tfR3G3B2: begin
      aData^ := Round(
        ((aPixel.Data.r and Range.r) shl Shift.r) or
        ((aPixel.Data.g and Range.g) shl Shift.g) or
        ((aPixel.Data.b and Range.b) shl Shift.b));
      inc(aData);
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TbmpColorTableFormat.Unmap(var aData: PByte; out aPixel: TglBitmapPixelData; var aMapData: Pointer);
var
  idx: QWord;
  s: Integer;
  bits: Byte;
  f: Single;
begin
  s    := Trunc(fPixelSize);
  f    := fPixelSize - s;
  bits := Round(8 * f);
  case s of
    0: idx :=          (aData^ shr (8 - bits - {%H-}PtrInt(aMapData))) and ((1 shl bits) - 1);
    1: idx :=           aData^;
    2: idx :=     PWord(aData)^;
    4: idx := PCardinal(aData)^;
    8: idx :=    PQWord(aData)^;
  else
    raise EglBitmap.CreateFmt('invalid pixel size: %.3f', [fPixelSize]);
  end;
  if (idx >= Length(fColorTable)) then
    raise EglBitmap.CreateFmt('invalid color index: %d', [idx]);
  with fColorTable[idx] do begin
    aPixel.Data.r := r;
    aPixel.Data.g := g;
    aPixel.Data.b := b;
    aPixel.Data.a := a;
  end;
  inc(PByte(aMapData), bits);
  if ({%H-}PtrUInt(aMapData) >= 8) then begin
    inc(aData, 1);
    dec(PByte(aMapData), 8);
  end;
  inc(aData, s);
end;

destructor TbmpColorTableFormat.Destroy;
begin
  SetLength(fColorTable, 0);
  inherited Destroy;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap - Helper//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapConvertPixel(var aPixel: TglBitmapPixelData; const aSourceFD, aDestFD: TFormatDescriptor);
var
  i: Integer;
begin
  for i := 0 to 3 do begin
    if (aSourceFD.Range.arr[i] <> aDestFD.Range.arr[i]) then begin
      if (aSourceFD.Range.arr[i] > 0) then
        aPixel.Data.arr[i] := Round(aPixel.Data.arr[i] / aSourceFD.Range.arr[i] * aDestFD.Range.arr[i])
      else
        aPixel.Data.arr[i] := aDestFD.Range.arr[i];
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapConvertCopyFunc(var aFuncRec: TglBitmapFunctionRec);
begin
  with aFuncRec do begin
    if (Source.Range.r   > 0) then
      Dest.Data.r := Source.Data.r;
    if (Source.Range.g > 0) then
      Dest.Data.g := Source.Data.g;
    if (Source.Range.b  > 0) then
      Dest.Data.b := Source.Data.b;
    if (Source.Range.a > 0) then
      Dest.Data.a := Source.Data.a;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapConvertCalculateRGBAFunc(var aFuncRec: TglBitmapFunctionRec);
var
  i: Integer;
begin
  with aFuncRec do begin
    for i := 0 to 3 do
      if (Source.Range.arr[i] > 0) then
        Dest.Data.arr[i] := Round(Dest.Range.arr[i] * Source.Data.arr[i] / Source.Range.arr[i]);
  end;
end;

type
  TShiftData = packed record
    case Integer of
      0: (r, g, b, a: SmallInt);
      1: (arr: array[0..3] of SmallInt);
  end;
  PShiftData = ^TShiftData;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapConvertShiftRGBAFunc(var aFuncRec: TglBitmapFunctionRec);
var
  i: Integer;
begin
  with aFuncRec do
    for i := 0 to 3 do
      if (Source.Range.arr[i] > 0) then
        Dest.Data.arr[i] := Source.Data.arr[i] shr PShiftData(Args)^.arr[i];
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapInvertFunc(var aFuncRec: TglBitmapFunctionRec);
begin
  with aFuncRec do begin
    Dest.Data := Source.Data;
    if ({%H-}PtrUInt(Args) and $1 > 0) then begin
      Dest.Data.r := Dest.Data.r xor Dest.Range.r;
      Dest.Data.g := Dest.Data.g xor Dest.Range.g;
      Dest.Data.b := Dest.Data.b xor Dest.Range.b;
    end;
    if ({%H-}PtrUInt(Args) and $2 > 0) then begin
      Dest.Data.a := Dest.Data.a xor Dest.Range.a;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapFillWithColorFunc(var aFuncRec: TglBitmapFunctionRec);
var
  i: Integer;
begin
  with aFuncRec do begin
    for i := 0 to 3 do
      Dest.Data.arr[i] := PglBitmapPixelData(Args)^.Data.arr[i];
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapAlphaFunc(var FuncRec: TglBitmapFunctionRec);
var
  Temp: Single;
begin
  with FuncRec do begin
    if (FuncRec.Args = nil) then begin //source has no alpha
      Temp :=
        Source.Data.r / Source.Range.r * ALPHA_WEIGHT_R +
        Source.Data.g / Source.Range.g * ALPHA_WEIGHT_G +
        Source.Data.b / Source.Range.b * ALPHA_WEIGHT_B;
      Dest.Data.a := Round(Dest.Range.a * Temp);
    end else
      Dest.Data.a := Round(Source.Data.a / Source.Range.a * Dest.Range.a);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapColorKeyAlphaFunc(var FuncRec: TglBitmapFunctionRec);
type
  PglBitmapPixelData = ^TglBitmapPixelData;
begin
  with FuncRec do begin
    Dest.Data.r := Source.Data.r;
    Dest.Data.g := Source.Data.g;
    Dest.Data.b := Source.Data.b;

    with PglBitmapPixelData(Args)^ do
      if ((Dest.Data.r <= Data.r) and (Dest.Data.r >= Range.r) and
          (Dest.Data.g <= Data.g) and (Dest.Data.g >= Range.g) and
          (Dest.Data.b <= Data.b) and (Dest.Data.b >= Range.b)) then
        Dest.Data.a := 0
      else
        Dest.Data.a := Dest.Range.a;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapValueAlphaFunc(var FuncRec: TglBitmapFunctionRec);
begin
  with FuncRec do begin
    Dest.Data.r := Source.Data.r;
    Dest.Data.g := Source.Data.g;
    Dest.Data.b := Source.Data.b;
    Dest.Data.a := PCardinal(Args)^;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure SwapRGB(aData: PByte; aWidth: Integer; const aHasAlpha: Boolean);
type
  PRGBPix = ^TRGBPix;
  TRGBPix = array [0..2] of byte;
var
  Temp: Byte;
begin
  while aWidth > 0 do begin
    Temp := PRGBPix(aData)^[0];
    PRGBPix(aData)^[0] := PRGBPix(aData)^[2];
    PRGBPix(aData)^[2] := Temp;

    if aHasAlpha then
      Inc(aData, 4)
    else
      Inc(aData, 3);
    dec(aWidth);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap - PROTECTED///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.GetFormatDesc: TglBitmapFormatDescriptor;
begin
  result := TFormatDescriptor.Get(Format);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.GetWidth: Integer;
begin
  if (ffX in fDimension.Fields) then
    result := fDimension.X
  else
    result := -1;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.GetHeight: Integer;
begin
  if (ffY in fDimension.Fields) then
    result := fDimension.Y
  else
    result := -1;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.GetFileWidth: Integer;
begin
  result := Max(1, Width);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.GetFileHeight: Integer;
begin
  result := Max(1, Height);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetCustomData(const aValue: Pointer);
begin
  if fCustomData = aValue then
    exit;
  fCustomData := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetCustomName(const aValue: String);
begin
  if fCustomName = aValue then
    exit;
  fCustomName := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetCustomNameW(const aValue: WideString);
begin
  if fCustomNameW = aValue then
    exit;
  fCustomNameW := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetDeleteTextureOnFree(const aValue: Boolean);
begin
  if fDeleteTextureOnFree = aValue then
    exit;
  fDeleteTextureOnFree := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetFormat(const aValue: TglBitmapFormat);
begin
  if fFormat = aValue then
    exit;
  if TFormatDescriptor.Get(Format).PixelSize <> TFormatDescriptor.Get(aValue).PixelSize then
    raise EglBitmapUnsupportedFormat.Create(Format);
  SetDataPointer(fData, aValue, Width, Height); //be careful, Data could be freed by this method
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetFreeDataAfterGenTexture(const aValue: Boolean);
begin
  if fFreeDataAfterGenTexture = aValue then
    exit;
  fFreeDataAfterGenTexture := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetID(const aValue: Cardinal);
begin
  if fID = aValue then
    exit;
  fID := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetMipMap(const aValue: TglBitmapMipMap);
begin
  if fMipMap = aValue then
    exit;
  fMipMap := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetTarget(const aValue: Cardinal);
begin
  if fTarget = aValue then
    exit;
  fTarget := aValue;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetAnisotropic(const aValue: Integer);
var
  MaxAnisotropic: Integer;
begin
  fAnisotropic := aValue;
  if (ID > 0) then begin
    if GL_EXT_texture_filter_anisotropic then begin
      if fAnisotropic > 0 then begin
        Bind(false);
        glGetIntegerv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, @MaxAnisotropic);
        if aValue > MaxAnisotropic then
          fAnisotropic := MaxAnisotropic;
        glTexParameteri(Target, GL_TEXTURE_MAX_ANISOTROPY_EXT, fAnisotropic);
      end;
    end else begin
      fAnisotropic := 0;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.CreateID;
begin
  if (ID <> 0) then
    glDeleteTextures(1, @fID);
  glGenTextures(1, @fID);
  Bind(false);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetupParameters(out aBuildWithGlu: Boolean);
begin
  // Set Up Parameters
  SetWrap(fWrapS, fWrapT, fWrapR);
  SetFilter(fFilterMin, fFilterMag);
  SetAnisotropic(fAnisotropic);
  SetBorderColor(fBorderColor[0], fBorderColor[1], fBorderColor[2], fBorderColor[3]);

  if (GL_ARB_texture_swizzle or GL_EXT_texture_swizzle or GL_VERSION_3_3) then
    SetSwizzle(fSwizzle[0], fSwizzle[1], fSwizzle[2], fSwizzle[3]);

  // Mip Maps Generation Mode
  aBuildWithGlu := false;
  if (MipMap = mmMipmap) then begin
    if (GL_VERSION_1_4 or GL_SGIS_generate_mipmap) then
      glTexParameteri(Target, GL_GENERATE_MIPMAP, GL_TRUE)
    else
      aBuildWithGlu := true;
  end else if (MipMap = mmMipmapGlu) then
    aBuildWithGlu := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
  const aWidth: Integer; const aHeight: Integer);
var
  s: Single;
begin
  if (Data <> aData) then begin
    if (Assigned(Data)) then
      FreeMem(Data);
    fData := aData;
  end;

  if not Assigned(fData) then begin
    fPixelSize := 0;
    fRowSize   := 0;
  end else begin
    FillChar(fDimension, SizeOf(fDimension), 0);
    if aWidth <> -1 then begin
      fDimension.Fields := fDimension.Fields + [ffX];
      fDimension.X := aWidth;
    end;

    if aHeight <> -1 then begin
      fDimension.Fields := fDimension.Fields + [ffY];
      fDimension.Y := aHeight;
    end;

    s := TFormatDescriptor.Get(aFormat).PixelSize;
    fFormat    := aFormat;
    fPixelSize := Ceil(s);
    fRowSize   := Ceil(s * aWidth);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.FlipHorz: Boolean;
begin
  result := false;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.FlipVert: Boolean;
begin
  result := false;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap - PUBLIC//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.AfterConstruction;
begin
  inherited AfterConstruction;

  fID         := 0;
  fTarget     := 0;
  fIsResident := false;

  fFormat                  := glBitmapGetDefaultFormat;
  fMipMap                  := glBitmapDefaultMipmap;
  fFreeDataAfterGenTexture := glBitmapGetDefaultFreeDataAfterGenTexture;
  fDeleteTextureOnFree     := glBitmapGetDefaultDeleteTextureOnFree;

  glBitmapGetDefaultFilter     (fFilterMin, fFilterMag);
  glBitmapGetDefaultTextureWrap(fWrapS, fWrapT, fWrapR);
  glBitmapGetDefaultSwizzle    (fSwizzle[0], fSwizzle[1], fSwizzle[2], fSwizzle[3]);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.BeforeDestruction;
var
  NewData: PByte;
begin
  NewData := nil;
  SetDataPointer(NewData, tfEmpty); //be careful, Data could be freed by this method
  if (fID > 0) and fDeleteTextureOnFree then
    glDeleteTextures(1, @fID);
  inherited BeforeDestruction;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.PrepareResType(var aResource: String; var aResType: PChar);
var
  TempPos: Integer;
begin
  if not Assigned(aResType) then begin
    TempPos   := Pos('.', aResource);
    aResType  := PChar(UpperCase(Copy(aResource, TempPos + 1, Length(aResource) - TempPos)));
    aResource := UpperCase(Copy(aResource, 0, TempPos -1));
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.LoadFromFile(const aFilename: String);
var
  fs: TFileStream;
begin
  if not FileExists(aFilename) then
    raise EglBitmap.Create('file does not exist: ' + aFilename);
  fFilename := aFilename;
  fs := TFileStream.Create(fFilename, fmOpenRead);
  try
    fs.Position := 0;
    LoadFromStream(fs);
  finally
    fs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.LoadFromStream(const aStream: TStream);
begin
  {$IFDEF GLB_SUPPORT_PNG_READ}
  if not LoadPNG(aStream) then
  {$ENDIF}
  {$IFDEF GLB_SUPPORT_JPEG_READ}
  if not LoadJPEG(aStream) then
  {$ENDIF}
  if not LoadDDS(aStream) then
  if not LoadTGA(aStream) then
  if not LoadBMP(aStream) then
    raise EglBitmap.Create('LoadFromStream - Couldn''t load Stream. It''s possible to be an unknow Streamtype.');
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.LoadFromFunc(const aSize: TglBitmapPixelPosition; const aFunc: TglBitmapFunction;
  const aFormat: TglBitmapFormat; const aArgs: Pointer);
var
  tmpData: PByte;
  size: Integer;
begin
  size := TFormatDescriptor.Get(aFormat).GetSize(aSize);
  GetMem(tmpData, size);
  try
    FillChar(tmpData^, size, #$FF);
    SetDataPointer(tmpData, aFormat, aSize.X, aSize.Y); //be careful, Data could be freed by this method
  except
    if Assigned(tmpData) then
      FreeMem(tmpData);
    raise;
  end;
  AddFunc(Self, aFunc, false, Format, aArgs);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.LoadFromResource(const aInstance: Cardinal; aResource: String; aResType: PChar);
var
  rs: TResourceStream;
begin
  PrepareResType(aResource, aResType);
  rs := TResourceStream.Create(aInstance, aResource, aResType);
  try
    LoadFromStream(rs);
  finally
    rs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.LoadFromResourceID(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar);
var
  rs: TResourceStream;
begin
  rs := TResourceStream.CreateFromID(aInstance, aResourceID, aResType);
  try
    LoadFromStream(rs);
  finally
    rs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveToFile(const aFileName: String; const aFileType: TglBitmapFileType);
var
  fs: TFileStream;
begin
  fs := TFileStream.Create(aFileName, fmCreate);
  try
    fs.Position := 0;
    SaveToStream(fs, aFileType);
  finally
    fs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveToStream(const aStream: TStream; const aFileType: TglBitmapFileType);
begin
  case aFileType of
    {$IFDEF GLB_SUPPORT_PNG_WRITE}
    ftPNG:  SavePNG(aStream);
    {$ENDIF}
    {$IFDEF GLB_SUPPORT_JPEG_WRITE}
    ftJPEG: SaveJPEG(aStream);
    {$ENDIF}
    ftDDS:  SaveDDS(aStream);
    ftTGA:  SaveTGA(aStream);
    ftBMP:  SaveBMP(aStream);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddFunc(const aFunc: TglBitmapFunction; const aCreateTemp: Boolean; const aArgs: Pointer): Boolean;
begin
  result := AddFunc(Self, aFunc, aCreateTemp, Format, aArgs);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddFunc(const aSource: TglBitmap; const aFunc: TglBitmapFunction; aCreateTemp: Boolean;
  const aFormat: TglBitmapFormat; const aArgs: Pointer): Boolean;
var
  DestData, TmpData, SourceData: pByte;
  TempHeight, TempWidth: Integer;
  SourceFD, DestFD: TFormatDescriptor;
  SourceMD, DestMD: Pointer;

  FuncRec: TglBitmapFunctionRec;
begin
  Assert(Assigned(Data));
  Assert(Assigned(aSource));
  Assert(Assigned(aSource.Data));

  result := false;
  if Assigned(aSource.Data) and ((aSource.Height > 0) or (aSource.Width > 0)) then begin
    SourceFD := TFormatDescriptor.Get(aSource.Format);
    DestFD   := TFormatDescriptor.Get(aFormat);

    if (SourceFD.IsCompressed) then
      raise EglBitmapUnsupportedFormat.Create('compressed formats are not supported: ', SourceFD.Format);
    if (DestFD.IsCompressed) then
      raise EglBitmapUnsupportedFormat.Create('compressed formats are not supported: ', DestFD.Format);

    // inkompatible Formats so CreateTemp
    if (SourceFD.PixelSize <> DestFD.PixelSize) then
      aCreateTemp := true;

    // Values
    TempHeight := Max(1, aSource.Height);
    TempWidth  := Max(1, aSource.Width);

    FuncRec.Sender := Self;
    FuncRec.Args   := aArgs;

    TmpData := nil;
    if aCreateTemp then begin
      GetMem(TmpData, DestFD.GetSize(TempWidth, TempHeight));
      DestData := TmpData;
    end else
      DestData := Data;

    try
      SourceFD.PreparePixel(FuncRec.Source);
      DestFD.PreparePixel  (FuncRec.Dest);

      SourceMD := SourceFD.CreateMappingData;
      DestMD   := DestFD.CreateMappingData;

      FuncRec.Size            := aSource.Dimension;
      FuncRec.Position.Fields := FuncRec.Size.Fields;

      try
        SourceData := aSource.Data;
        FuncRec.Position.Y := 0;
        while FuncRec.Position.Y < TempHeight do begin
          FuncRec.Position.X := 0;
          while FuncRec.Position.X < TempWidth do begin
            SourceFD.Unmap(SourceData, FuncRec.Source, SourceMD);
            aFunc(FuncRec);
            DestFD.Map(FuncRec.Dest, DestData, DestMD);
            inc(FuncRec.Position.X);
          end;
          inc(FuncRec.Position.Y);
        end;

        // Updating Image or InternalFormat
        if aCreateTemp then
          SetDataPointer(TmpData, aFormat, aSource.Width, aSource.Height) //be careful, Data could be freed by this method
        else if (aFormat <> fFormat) then
          Format := aFormat;

        result := true;
      finally
        SourceFD.FreeMappingData(SourceMD);
        DestFD.FreeMappingData(DestMD);
      end;
    except
      if aCreateTemp and Assigned(TmpData) then
        FreeMem(TmpData);
      raise;
    end;
  end;
end;

{$IFDEF GLB_SDL}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignToSurface(out aSurface: PSDL_Surface): Boolean;
var
  Row, RowSize: Integer;
  SourceData, TmpData: PByte;
  TempDepth: Integer;
  FormatDesc: TFormatDescriptor;

  function GetRowPointer(Row: Integer): pByte;
  begin
    result := aSurface.pixels;
    Inc(result, Row * RowSize);
  end;

begin
  result := false;

  FormatDesc := TFormatDescriptor.Get(Format);
  if FormatDesc.IsCompressed then
    raise EglBitmapUnsupportedFormat.Create(Format);

  if Assigned(Data) then begin
    case Trunc(FormatDesc.PixelSize) of
      1: TempDepth :=  8;
      2: TempDepth := 16;
      3: TempDepth := 24;
      4: TempDepth := 32;
    else
      raise EglBitmapUnsupportedFormat.Create(Format);
    end;

    aSurface := SDL_CreateRGBSurface(SDL_SWSURFACE, Width, Height, TempDepth,
      FormatDesc.RedMask, FormatDesc.GreenMask, FormatDesc.BlueMask, FormatDesc.AlphaMask);
    SourceData := Data;
    RowSize    := FormatDesc.GetSize(FileWidth, 1);

    for Row := 0 to FileHeight-1 do begin
      TmpData := GetRowPointer(Row);
      if Assigned(TmpData) then begin
        Move(SourceData^, TmpData^, RowSize);
        inc(SourceData, RowSize);
      end;
    end;
    result := true;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignFromSurface(const aSurface: PSDL_Surface): Boolean;
var
  pSource, pData, pTempData: PByte;
  Row, RowSize, TempWidth, TempHeight: Integer;
  IntFormat: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;

  function GetRowPointer(Row: Integer): pByte;
  begin
    result := aSurface^.pixels;
    Inc(result, Row * RowSize);
  end;

begin
  result := false;
  if (Assigned(aSurface)) then begin
    with aSurface^.format^ do begin
      for IntFormat := High(TglBitmapFormat) to Low(TglBitmapFormat) do begin
        FormatDesc := TFormatDescriptor.Get(IntFormat);
        if (FormatDesc.MaskMatch(RMask, GMask, BMask, AMask)) then
          break;
      end;
      if (IntFormat = tfEmpty) then
        raise EglBitmapException.Create('AssignFromSurface - Invalid Pixelformat.');
    end;

    TempWidth  := aSurface^.w;
    TempHeight := aSurface^.h;
    RowSize := FormatDesc.GetSize(TempWidth, 1);
    GetMem(pData, TempHeight * RowSize);
    try
      pTempData := pData;
      for Row := 0 to TempHeight -1 do begin
        pSource := GetRowPointer(Row);
        if (Assigned(pSource)) then begin
          Move(pSource^, pTempData^, RowSize);
          Inc(pTempData, RowSize);
        end;
      end;
      SetDataPointer(pData, IntFormat, TempWidth, TempHeight); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(pData) then
        FreeMem(pData);
      raise;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignAlphaToSurface(out aSurface: PSDL_Surface): Boolean;
var
  Row, Col, AlphaInterleave: Integer;
  pSource, pDest: PByte;

  function GetRowPointer(Row: Integer): pByte;
  begin
    result := aSurface.pixels;
    Inc(result, Row * Width);
  end;

begin
  result := false;
  if Assigned(Data) then begin
    if Format in [tfAlpha8, tfLuminance8Alpha8, tfBGRA8, tfRGBA8] then begin
      aSurface := SDL_CreateRGBSurface(SDL_SWSURFACE, Width, Height, 8, $FF, $FF, $FF, 0);

      AlphaInterleave := 0;
      case Format of
        tfLuminance8Alpha8:
          AlphaInterleave := 1;
        tfBGRA8, tfRGBA8:
          AlphaInterleave := 3;
      end;

      pSource := Data;
      for Row := 0 to Height -1 do begin
        pDest := GetRowPointer(Row);
        if Assigned(pDest) then begin
          for Col := 0 to Width -1 do begin
            Inc(pSource, AlphaInterleave);
            pDest^ := pSource^;
            Inc(pDest);
            Inc(pSource);
          end;
        end;
      end;
      result := true;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromSurface(const aSurface: PSDL_Surface; const aFunc: TglBitmapFunction = nil; const aArgs: Pointer = nil): Boolean;
var
  bmp: TglBitmap2D;
begin
  bmp := TglBitmap2D.Create;
  try
    bmp.AssignFromSurface(aSurface);
    result := AddAlphaFromGlBitmap(bmp, aFunc, aArgs);
  finally
    bmp.Free;
  end;
end;
{$ENDIF}

{$IFDEF GLB_DELPHI}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function CreateGrayPalette: HPALETTE;
var
  Idx: Integer;
  Pal: PLogPalette;
begin
  GetMem(Pal, SizeOf(TLogPalette) + (SizeOf(TPaletteEntry) * 256));

  Pal.palVersion := $300;
  Pal.palNumEntries := 256;

  for Idx := 0 to Pal.palNumEntries - 1 do begin
    Pal.palPalEntry[Idx].peRed   := Idx;
    Pal.palPalEntry[Idx].peGreen := Idx;
    Pal.palPalEntry[Idx].peBlue  := Idx;
    Pal.palPalEntry[Idx].peFlags := 0;
  end;
  Result := CreatePalette(Pal^);
  FreeMem(Pal);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignToBitmap(const aBitmap: TBitmap): Boolean;
var
  Row: Integer;
  pSource, pData: PByte;
begin
  result := false;
  if Assigned(Data) then begin
    if Assigned(aBitmap) then begin
      aBitmap.Width  := Width;
      aBitmap.Height := Height;

      case Format of
        tfAlpha8, tfLuminance8: begin
          aBitmap.PixelFormat := pf8bit;
          aBitmap.Palette     := CreateGrayPalette;
        end;
        tfRGB5A1:
          aBitmap.PixelFormat := pf15bit;
        tfR5G6B5:
          aBitmap.PixelFormat := pf16bit;
        tfRGB8, tfBGR8:
          aBitmap.PixelFormat := pf24bit;
        tfRGBA8, tfBGRA8:
          aBitmap.PixelFormat := pf32bit;
      else
        raise EglBitmap.Create('AssignToBitmap - Invalid Pixelformat.');
      end;

      pSource := Data;
      for Row := 0 to FileHeight -1 do begin
        pData := aBitmap.Scanline[Row];
        Move(pSource^, pData^, fRowSize);
        Inc(pSource, fRowSize);
        if (Format in [tfRGB8, tfRGBA8]) then        // swap RGB(A) to BGR(A)
          SwapRGB(pData, FileWidth, Format = tfRGBA8);
      end;
      result := true;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignFromBitmap(const aBitmap: TBitmap): Boolean;
var
  pSource, pData, pTempData: PByte;
  Row, RowSize, TempWidth, TempHeight: Integer;
  IntFormat: TglBitmapFormat;
begin
  result := false;

  if (Assigned(aBitmap)) then begin
    case aBitmap.PixelFormat of
      pf8bit:
        IntFormat := tfLuminance8;
      pf15bit:
        IntFormat := tfRGB5A1;
      pf16bit:
        IntFormat := tfR5G6B5;
      pf24bit:
        IntFormat := tfBGR8;
      pf32bit:
        IntFormat := tfBGRA8;
    else
      raise EglBitmap.Create('AssignFromBitmap - Invalid Pixelformat.');
    end;

    TempWidth  := aBitmap.Width;
    TempHeight := aBitmap.Height;
    RowSize    := TFormatDescriptor.Get(IntFormat).GetSize(TempWidth, 1);
    GetMem(pData, TempHeight * RowSize);
    try
      pTempData := pData;
      for Row := 0 to TempHeight -1 do begin
        pSource := aBitmap.Scanline[Row];
        if (Assigned(pSource)) then begin
          Move(pSource^, pTempData^, RowSize);
          Inc(pTempData, RowSize);
        end;
      end;
      SetDataPointer(pData, IntFormat, TempWidth, TempHeight); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(pData) then
        FreeMem(pData);
      raise;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignAlphaToBitmap(const aBitmap: TBitmap): Boolean;
var
  Row, Col, AlphaInterleave: Integer;
  pSource, pDest: PByte;
begin
  result := false;

  if Assigned(Data) then begin
    if (Format in [tfAlpha8, tfLuminance8Alpha8, tfRGBA8, tfBGRA8]) then begin
      if Assigned(aBitmap) then begin
        aBitmap.PixelFormat := pf8bit;
        aBitmap.Palette     := CreateGrayPalette;
        aBitmap.Width       := Width;
        aBitmap.Height      := Height;

        case Format of
          tfLuminance8Alpha8:
            AlphaInterleave := 1;
          tfRGBA8, tfBGRA8:
            AlphaInterleave := 3;
          else
            AlphaInterleave := 0;
        end;

        // Copy Data
        pSource := Data;

        for Row := 0 to Height -1 do begin
          pDest := aBitmap.Scanline[Row];
          if Assigned(pDest) then begin
            for Col := 0 to Width -1 do begin
              Inc(pSource, AlphaInterleave);
              pDest^ := pSource^;
              Inc(pDest);
              Inc(pSource);
            end;
          end;
        end;
        result := true;
      end;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromBitmap(const aBitmap: TBitmap; const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  tex: TglBitmap2D;
begin
  tex := TglBitmap2D.Create;
  try
    tex.AssignFromBitmap(ABitmap);
    result := AddAlphaFromglBitmap(tex, aFunc, aArgs);
  finally
    tex.Free;
  end;
end;
{$ENDIF}

{$IFDEF GLB_LAZARUS}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignToLazIntfImage(const aImage: TLazIntfImage): Boolean;
var
  rid: TRawImageDescription;
  FormatDesc: TFormatDescriptor;
begin
  result := false;
  if not Assigned(aImage) or (Format = tfEmpty) then
    exit;
  FormatDesc := TFormatDescriptor.Get(Format);
  if FormatDesc.IsCompressed then
    exit;

  FillChar(rid{%H-}, SizeOf(rid), 0);
  if (Format in [
       tfAlpha4, tfAlpha8, tfAlpha12, tfAlpha16,
       tfLuminance4, tfLuminance8, tfLuminance12, tfLuminance16,
       tfLuminance4Alpha4, tfLuminance8Alpha8, tfLuminance12Alpha4, tfLuminance12Alpha12, tfLuminance16Alpha16]) then
    rid.Format := ricfGray
  else
    rid.Format := ricfRGBA;

  rid.Width        := Width;
  rid.Height       := Height;
  rid.Depth        := CountSetBits(FormatDesc.Range.r or FormatDesc.Range.g or FormatDesc.Range.b or FormatDesc.Range.a);
  rid.BitOrder     := riboBitsInOrder;
  rid.ByteOrder    := riboLSBFirst;
  rid.LineOrder    := riloTopToBottom;
  rid.LineEnd      := rileTight;
  rid.BitsPerPixel := Round(8 * FormatDesc.PixelSize);
  rid.RedPrec      := CountSetBits(FormatDesc.Range.r);
  rid.GreenPrec    := CountSetBits(FormatDesc.Range.g);
  rid.BluePrec     := CountSetBits(FormatDesc.Range.b);
  rid.AlphaPrec    := CountSetBits(FormatDesc.Range.a);
  rid.RedShift     := FormatDesc.Shift.r;
  rid.GreenShift   := FormatDesc.Shift.g;
  rid.BlueShift    := FormatDesc.Shift.b;
  rid.AlphaShift   := FormatDesc.Shift.a;

  rid.MaskBitsPerPixel  := 0;
  rid.PaletteColorCount := 0;

  aImage.DataDescription := rid;
  aImage.CreateData;

  Move(Data^, aImage.PixelData^, FormatDesc.GetSize(Dimension));

  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignFromLazIntfImage(const aImage: TLazIntfImage): Boolean;
var
  f: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;
  ImageData: PByte;
  ImageSize: Integer;
begin
  result := false;
  if not Assigned(aImage) then
    exit;
  for f := High(f) downto Low(f) do begin
    FormatDesc := TFormatDescriptor.Get(f);
    with aImage.DataDescription do
      if FormatDesc.MaskMatch(
        (QWord(1 shl RedPrec  )-1) shl RedShift,
        (QWord(1 shl GreenPrec)-1) shl GreenShift,
        (QWord(1 shl BluePrec )-1) shl BlueShift,
        (QWord(1 shl AlphaPrec)-1) shl AlphaShift) then
        break;
  end;

  if (f = tfEmpty) then
    exit;

  ImageSize := FormatDesc.GetSize(aImage.Width, aImage.Height);
  ImageData := GetMem(ImageSize);
  try
    Move(aImage.PixelData^, ImageData^, (aImage.Width * aImage.Height * aImage.DataDescription.BitsPerPixel) shr 3);
    SetDataPointer(ImageData, f, aImage.Width, aImage.Height); //be careful, Data could be freed by this method
  except
    if Assigned(ImageData) then
      FreeMem(ImageData);
    raise;
  end;

  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AssignAlphaToLazIntfImage(const aImage: TLazIntfImage): Boolean;
var
  rid: TRawImageDescription;
  FormatDesc: TFormatDescriptor;
  Pixel: TglBitmapPixelData;
  x, y: Integer;
  srcMD: Pointer;
  src, dst: PByte;
begin
  result := false;
  if not Assigned(aImage) or (Format = tfEmpty) then
    exit;
  FormatDesc := TFormatDescriptor.Get(Format);
  if FormatDesc.IsCompressed or not FormatDesc.HasAlpha then
    exit;

  FillChar(rid{%H-}, SizeOf(rid), 0);
  rid.Format       := ricfGray;
  rid.Width        := Width;
  rid.Height       := Height;
  rid.Depth        := CountSetBits(FormatDesc.Range.a);
  rid.BitOrder     := riboBitsInOrder;
  rid.ByteOrder    := riboLSBFirst;
  rid.LineOrder    := riloTopToBottom;
  rid.LineEnd      := rileTight;
  rid.BitsPerPixel := 8 * Ceil(rid.Depth / 8);
  rid.RedPrec      := CountSetBits(FormatDesc.Range.a);
  rid.GreenPrec    := 0;
  rid.BluePrec     := 0;
  rid.AlphaPrec    := 0;
  rid.RedShift     := 0;
  rid.GreenShift   := 0;
  rid.BlueShift    := 0;
  rid.AlphaShift   := 0;

  rid.MaskBitsPerPixel  := 0;
  rid.PaletteColorCount := 0;

  aImage.DataDescription := rid;
  aImage.CreateData;

  srcMD := FormatDesc.CreateMappingData;
  try
    FormatDesc.PreparePixel(Pixel);
    src := Data;
    dst := aImage.PixelData;
    for y := 0 to Height-1 do
      for x := 0 to Width-1 do begin
        FormatDesc.Unmap(src, Pixel, srcMD);
        case rid.BitsPerPixel of
           8: begin
            dst^ := Pixel.Data.a;
            inc(dst);
          end;
          16: begin
            PWord(dst)^ := Pixel.Data.a;
            inc(dst, 2);
          end;
          24: begin
            PByteArray(dst)^[0] := PByteArray(@Pixel.Data.a)^[0];
            PByteArray(dst)^[1] := PByteArray(@Pixel.Data.a)^[1];
            PByteArray(dst)^[2] := PByteArray(@Pixel.Data.a)^[2];
            inc(dst, 3);
          end;
          32: begin
            PCardinal(dst)^ := Pixel.Data.a;
            inc(dst, 4);
          end;
        else
          raise EglBitmapUnsupportedFormat.Create(Format);
        end;
      end;
  finally
    FormatDesc.FreeMappingData(srcMD);
  end;
  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromLazIntfImage(const aImage: TLazIntfImage; const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  tex: TglBitmap2D;
begin
  tex := TglBitmap2D.Create;
  try
    tex.AssignFromLazIntfImage(aImage);
    result := AddAlphaFromglBitmap(tex, aFunc, aArgs);
  finally
    tex.Free;
  end;
end;
{$ENDIF}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromResource(const aInstance: Cardinal; aResource: String; aResType: PChar;
  const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  rs: TResourceStream;
begin
  PrepareResType(aResource, aResType);
  rs := TResourceStream.Create(aInstance, aResource, aResType);
  try
    result := AddAlphaFromStream(rs, aFunc, aArgs);
  finally
    rs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromResourceID(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar;
  const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  rs: TResourceStream;
begin
  rs := TResourceStream.CreateFromID(aInstance, aResourceID, aResType);
  try
    result := AddAlphaFromStream(rs, aFunc, aArgs);
  finally
    rs.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromFunc(const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
begin
  if TFormatDescriptor.Get(Format).IsCompressed then
    raise EglBitmapUnsupportedFormat.Create(Format);
  result := AddFunc(Self, aFunc, false, TFormatDescriptor.Get(Format).WithAlpha, aArgs);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromFile(const aFileName: String; const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  FS: TFileStream;
begin
  FS := TFileStream.Create(aFileName, fmOpenRead);
  try
    result := AddAlphaFromStream(FS, aFunc, aArgs);
  finally
    FS.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromStream(const aStream: TStream; const aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  tex: TglBitmap2D;
begin
  tex := TglBitmap2D.Create(aStream);
  try
    result := AddAlphaFromglBitmap(tex, aFunc, aArgs);
  finally
    tex.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromGlBitmap(const aBitmap: TglBitmap; aFunc: TglBitmapFunction; const aArgs: Pointer): Boolean;
var
  DestData, DestData2, SourceData: pByte;
  TempHeight, TempWidth: Integer;
  SourceFD, DestFD: TFormatDescriptor;
  SourceMD, DestMD, DestMD2: Pointer;

  FuncRec: TglBitmapFunctionRec;
begin
  result := false;

  Assert(Assigned(Data));
  Assert(Assigned(aBitmap));
  Assert(Assigned(aBitmap.Data));

  if ((aBitmap.Width = Width) and (aBitmap.Height = Height)) then begin
    result := ConvertTo(TFormatDescriptor.Get(Format).WithAlpha);

    SourceFD := TFormatDescriptor.Get(aBitmap.Format);
    DestFD   := TFormatDescriptor.Get(Format);

    if not Assigned(aFunc) then begin
      aFunc        := glBitmapAlphaFunc;
      FuncRec.Args := {%H-}Pointer(SourceFD.HasAlpha);
    end else
      FuncRec.Args := aArgs;

    // Values
    TempHeight := aBitmap.FileHeight;
    TempWidth  := aBitmap.FileWidth;

    FuncRec.Sender          := Self;
    FuncRec.Size            := Dimension;
    FuncRec.Position.Fields := FuncRec.Size.Fields;

    DestData   := Data;
    DestData2  := Data;
    SourceData := aBitmap.Data;

    // Mapping
    SourceFD.PreparePixel(FuncRec.Source);
    DestFD.PreparePixel  (FuncRec.Dest);

    SourceMD := SourceFD.CreateMappingData;
    DestMD   := DestFD.CreateMappingData;
    DestMD2  := DestFD.CreateMappingData;
    try
      FuncRec.Position.Y := 0;
      while FuncRec.Position.Y < TempHeight do begin
        FuncRec.Position.X := 0;
        while FuncRec.Position.X < TempWidth do begin
          SourceFD.Unmap(SourceData, FuncRec.Source, SourceMD);
          DestFD.Unmap  (DestData,   FuncRec.Dest,   DestMD);
          aFunc(FuncRec);
          DestFD.Map(FuncRec.Dest, DestData2, DestMD2);
          inc(FuncRec.Position.X);
        end;
        inc(FuncRec.Position.Y);
      end;
    finally
      SourceFD.FreeMappingData(SourceMD);
      DestFD.FreeMappingData(DestMD);
      DestFD.FreeMappingData(DestMD2);
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromColorKey(const aRed, aGreen, aBlue: Byte; const aDeviation: Byte): Boolean;
begin
  result := AddAlphaFromColorKeyFloat(aRed / $FF, aGreen / $FF, aBlue / $FF, aDeviation / $FF);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromColorKeyRange(const aRed, aGreen, aBlue: Cardinal; const aDeviation: Cardinal): Boolean;
var
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.GetWithAlpha(Format).PreparePixel(PixelData);
  result := AddAlphaFromColorKeyFloat(
    aRed   / PixelData.Range.r,
    aGreen / PixelData.Range.g,
    aBlue  / PixelData.Range.b,
    aDeviation / Max(PixelData.Range.r, Max(PixelData.Range.g, PixelData.Range.b)));
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromColorKeyFloat(const aRed, aGreen, aBlue: Single; const aDeviation: Single): Boolean;
var
  values: array[0..2] of Single;
  tmp: Cardinal;
  i: Integer;
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.GetWithAlpha(Format).PreparePixel(PixelData);
  with PixelData do begin
    values[0] := aRed;
    values[1] := aGreen;
    values[2] := aBlue;

    for i := 0 to 2 do begin
      tmp          := Trunc(Range.arr[i] * aDeviation);
      Data.arr[i]  := Min(Range.arr[i], Trunc(Range.arr[i] * values[i] + tmp));
      Range.arr[i] := Max(0,            Trunc(Range.arr[i] * values[i] - tmp));
    end;
    Data.a  := 0;
    Range.a := 0;
  end;
  result := AddAlphaFromFunc(glBitmapColorKeyAlphaFunc, @PixelData);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromValue(const aAlpha: Byte): Boolean;
begin
  result := AddAlphaFromValueFloat(aAlpha / $FF);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromValueRange(const aAlpha: Cardinal): Boolean;
var
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.GetWithAlpha(Format).PreparePixel(PixelData);
  result := AddAlphaFromValueFloat(aAlpha / PixelData.Range.a);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.AddAlphaFromValueFloat(const aAlpha: Single): Boolean;
var
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.GetWithAlpha(Format).PreparePixel(PixelData);
  with PixelData do
    Data.a := Min(Range.a, Max(0, Round(Range.a * aAlpha)));
  result := AddAlphaFromFunc(glBitmapValueAlphaFunc, @PixelData.Data.a);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.RemoveAlpha: Boolean;
var
  FormatDesc: TFormatDescriptor;
begin
  result := false;
  FormatDesc := TFormatDescriptor.Get(Format);
  if Assigned(Data) then begin
    if FormatDesc.IsCompressed or not FormatDesc.HasAlpha then
      raise EglBitmapUnsupportedFormat.Create(Format);
    result := ConvertTo(FormatDesc.WithoutAlpha);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.Clone: TglBitmap;
var
  Temp: TglBitmap;
  TempPtr: PByte;
  Size: Integer;
begin
  result := nil;
  Temp := (ClassType.Create as TglBitmap);
  try
    // copy texture data if assigned
    if Assigned(Data) then begin
      Size := TFormatDescriptor.Get(Format).GetSize(fDimension);
      GetMem(TempPtr, Size);
      try
        Move(Data^, TempPtr^, Size);
        Temp.SetDataPointer(TempPtr, Format, Width, Height); //be careful, Data could be freed by this method
      except
        if Assigned(TempPtr) then
          FreeMem(TempPtr);
        raise;
      end;
    end else begin
      TempPtr := nil;
      Temp.SetDataPointer(TempPtr, Format, Width, Height); //be careful, Data could be freed by this method
    end;

	// copy properties
    Temp.fID                      := ID;
    Temp.fTarget                  := Target;
    Temp.fFormat                  := Format;
    Temp.fMipMap                  := MipMap;
    Temp.fAnisotropic             := Anisotropic;
    Temp.fBorderColor             := fBorderColor;
    Temp.fDeleteTextureOnFree     := DeleteTextureOnFree;
    Temp.fFreeDataAfterGenTexture := FreeDataAfterGenTexture;
    Temp.fFilterMin               := fFilterMin;
    Temp.fFilterMag               := fFilterMag;
    Temp.fWrapS                   := fWrapS;
    Temp.fWrapT                   := fWrapT;
    Temp.fWrapR                   := fWrapR;
    Temp.fFilename                := fFilename;
    Temp.fCustomName              := fCustomName;
    Temp.fCustomNameW             := fCustomNameW;
    Temp.fCustomData              := fCustomData;

    result := Temp;
  except
    FreeAndNil(Temp);
    raise;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.ConvertTo(const aFormat: TglBitmapFormat): Boolean;
var
  SourceFD, DestFD: TFormatDescriptor;
  SourcePD, DestPD: TglBitmapPixelData;
  ShiftData: TShiftData;

  function CanCopyDirect: Boolean;
  begin
    result :=
      ((SourcePD.Range.r = DestPD.Range.r) or (SourcePD.Range.r = 0) or (DestPD.Range.r = 0)) and
      ((SourcePD.Range.g = DestPD.Range.g) or (SourcePD.Range.g = 0) or (DestPD.Range.g = 0)) and
      ((SourcePD.Range.b = DestPD.Range.b) or (SourcePD.Range.b = 0) or (DestPD.Range.b = 0)) and
      ((SourcePD.Range.a = DestPD.Range.a) or (SourcePD.Range.a = 0) or (DestPD.Range.a = 0));
  end;

  function CanShift: Boolean;
  begin
    result :=
      ((SourcePD.Range.r >= DestPD.Range.r) or (SourcePD.Range.r = 0) or (DestPD.Range.r = 0)) and
      ((SourcePD.Range.g >= DestPD.Range.g) or (SourcePD.Range.g = 0) or (DestPD.Range.g = 0)) and
      ((SourcePD.Range.b >= DestPD.Range.b) or (SourcePD.Range.b = 0) or (DestPD.Range.b = 0)) and
      ((SourcePD.Range.a >= DestPD.Range.a) or (SourcePD.Range.a = 0) or (DestPD.Range.a = 0));
  end;

  function GetShift(aSource, aDest: Cardinal) : ShortInt;
  begin
    result := 0;
    while (aSource > aDest) and (aSource > 0) do begin
      inc(result);
      aSource := aSource shr 1;
    end;
  end;

begin
  if (aFormat <> fFormat) and (aFormat <> tfEmpty) then begin
    SourceFD := TFormatDescriptor.Get(Format);
    DestFD   := TFormatDescriptor.Get(aFormat);

    SourceFD.PreparePixel(SourcePD);
    DestFD.PreparePixel  (DestPD);

    if CanCopyDirect then
      result := AddFunc(Self, glBitmapConvertCopyFunc, false, aFormat)
    else if CanShift then begin
      ShiftData.r := GetShift(SourcePD.Range.r, DestPD.Range.r);
      ShiftData.g := GetShift(SourcePD.Range.g, DestPD.Range.g);
      ShiftData.b := GetShift(SourcePD.Range.b, DestPD.Range.b);
      ShiftData.a := GetShift(SourcePD.Range.a, DestPD.Range.a);
      result := AddFunc(Self, glBitmapConvertShiftRGBAFunc, false, aFormat, @ShiftData);
    end else
      result := AddFunc(Self, glBitmapConvertCalculateRGBAFunc, false, aFormat);
  end else
    result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.Invert(const aUseRGB: Boolean; const aUseAlpha: Boolean);
begin
  if aUseRGB or aUseAlpha then
    AddFunc(glBitmapInvertFunc, false, {%H-}Pointer(
      ((Byte(aUseAlpha) and 1) shl 1) or
       (Byte(aUseRGB)   and 1)      ));
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetBorderColor(const aRed, aGreen, aBlue, aAlpha: Single);
begin
  fBorderColor[0] := aRed;
  fBorderColor[1] := aGreen;
  fBorderColor[2] := aBlue;
  fBorderColor[3] := aAlpha;
  if (ID > 0) then begin
    Bind(false);
    glTexParameterfv(Target, GL_TEXTURE_BORDER_COLOR, @fBorderColor[0]);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.FreeData;
var
  TempPtr: PByte;
begin
  TempPtr := nil;
  SetDataPointer(TempPtr, tfEmpty); //be careful, Data could be freed by this method
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.FillWithColor(const aRed, aGreen, aBlue: Byte;
  const aAlpha: Byte);
begin
  FillWithColorFloat(aRed/$FF, aGreen/$FF, aBlue/$FF, aAlpha/$FF);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.FillWithColorRange(const aRed, aGreen, aBlue: Cardinal; const aAlpha: Cardinal);
var
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.GetWithAlpha(Format).PreparePixel(PixelData);
  FillWithColorFloat(
    aRed   / PixelData.Range.r,
    aGreen / PixelData.Range.g,
    aBlue  / PixelData.Range.b,
    aAlpha / PixelData.Range.a);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.FillWithColorFloat(const aRed, aGreen, aBlue: Single; const aAlpha: Single);
var
  PixelData: TglBitmapPixelData;
begin
  TFormatDescriptor.Get(Format).PreparePixel(PixelData);
  with PixelData do begin
    Data.r := Max(0, Min(Range.r, Trunc(Range.r * aRed)));
    Data.g := Max(0, Min(Range.g, Trunc(Range.g * aGreen)));
    Data.b := Max(0, Min(Range.b, Trunc(Range.b * aBlue)));
    Data.a := Max(0, Min(Range.a, Trunc(Range.a * aAlpha)));
  end;
  AddFunc(glBitmapFillWithColorFunc, false, @PixelData);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetFilter(const aMin, aMag: GLenum);
begin
  //check MIN filter
  case aMin of
    GL_NEAREST:
      fFilterMin := GL_NEAREST;
    GL_LINEAR:
      fFilterMin := GL_LINEAR;
    GL_NEAREST_MIPMAP_NEAREST:
      fFilterMin := GL_NEAREST_MIPMAP_NEAREST;
    GL_LINEAR_MIPMAP_NEAREST:
      fFilterMin := GL_LINEAR_MIPMAP_NEAREST;
    GL_NEAREST_MIPMAP_LINEAR:
      fFilterMin := GL_NEAREST_MIPMAP_LINEAR;
    GL_LINEAR_MIPMAP_LINEAR:
      fFilterMin := GL_LINEAR_MIPMAP_LINEAR;
    else
      raise EglBitmap.Create('SetFilter - Unknow MIN filter.');
  end;

  //check MAG filter
  case aMag of
    GL_NEAREST:
      fFilterMag := GL_NEAREST;
    GL_LINEAR:
      fFilterMag := GL_LINEAR;
    else
      raise EglBitmap.Create('SetFilter - Unknow MAG filter.');
  end;

  //apply filter
  if (ID > 0) then begin
    Bind(false);
    glTexParameteri(Target, GL_TEXTURE_MAG_FILTER, fFilterMag);

    if (MipMap = mmNone) or (Target = GL_TEXTURE_RECTANGLE) then begin
      case fFilterMin of
        GL_NEAREST, GL_LINEAR:
          glTexParameteri(Target, GL_TEXTURE_MIN_FILTER, fFilterMin);
        GL_NEAREST_MIPMAP_NEAREST, GL_NEAREST_MIPMAP_LINEAR:
          glTexParameteri(Target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
        GL_LINEAR_MIPMAP_NEAREST, GL_LINEAR_MIPMAP_LINEAR:
          glTexParameteri(Target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
      end;
    end else
      glTexParameteri(Target, GL_TEXTURE_MIN_FILTER, fFilterMin);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetWrap(const S: GLenum; const T: GLenum; const R: GLenum);

  procedure CheckAndSetWrap(const aValue: Cardinal; var aTarget: Cardinal);
  begin
    case aValue of
      GL_CLAMP:
        aTarget := GL_CLAMP;

      GL_REPEAT:
        aTarget := GL_REPEAT;

      GL_CLAMP_TO_EDGE: begin
        if GL_VERSION_1_2 or GL_EXT_texture_edge_clamp then
          aTarget := GL_CLAMP_TO_EDGE
        else
          aTarget := GL_CLAMP;
      end;

      GL_CLAMP_TO_BORDER: begin
        if GL_VERSION_1_3 or GL_ARB_texture_border_clamp then
          aTarget := GL_CLAMP_TO_BORDER
        else
          aTarget := GL_CLAMP;
      end;

      GL_MIRRORED_REPEAT: begin
        if GL_VERSION_1_4 or GL_ARB_texture_mirrored_repeat or GL_IBM_texture_mirrored_repeat then
          aTarget := GL_MIRRORED_REPEAT
        else
          raise EglBitmap.Create('SetWrap - Unsupported Texturewrap GL_MIRRORED_REPEAT (S).');
      end;
    else
      raise EglBitmap.Create('SetWrap - Unknow Texturewrap');
    end;
  end;

begin
  CheckAndSetWrap(S, fWrapS);
  CheckAndSetWrap(T, fWrapT);
  CheckAndSetWrap(R, fWrapR);

  if (ID > 0) then begin
    Bind(false);
    glTexParameteri(Target, GL_TEXTURE_WRAP_S, fWrapS);
    glTexParameteri(Target, GL_TEXTURE_WRAP_T, fWrapT);
    glTexParameteri(Target, GL_TEXTURE_WRAP_R, fWrapR);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SetSwizzle(const r, g, b, a: GLenum);

  procedure CheckAndSetValue(const aValue: GLenum; const aIndex: Integer);
  begin
    if (aValue = GL_ZERO) or (aValue =   GL_ONE) or (aValue = GL_ALPHA) or
       (aValue =  GL_RED) or (aValue = GL_GREEN) or (aValue =  GL_BLUE) then
      fSwizzle[aIndex] := aValue
    else
      raise EglBitmap.Create('SetSwizzle - Unknow Swizle Value');
  end;

begin
  if not (GL_ARB_texture_swizzle or GL_EXT_texture_swizzle or GL_VERSION_3_3) then
    raise EglBitmapNotSupported.Create('texture swizzle is not supported');
  CheckAndSetValue(r, 0);
  CheckAndSetValue(g, 1);
  CheckAndSetValue(b, 2);
  CheckAndSetValue(a, 3);

  if (ID > 0) then begin
    Bind(false);
    glTexParameteriv(Target, GL_TEXTURE_SWIZZLE_RGBA, @fSwizzle[0]);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.Bind(const aEnableTextureUnit: Boolean);
begin
  if aEnableTextureUnit then
    glEnable(Target);
  if (ID > 0) then
    glBindTexture(Target, ID);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.Unbind(const aDisableTextureUnit: Boolean);
begin
  if aDisableTextureUnit then
    glDisable(Target);
  glBindTexture(Target, 0);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create;
begin
  if (ClassType = TglBitmap) then
    raise EglBitmap.Create('Don''t create TglBitmap directly. Use one of the deviated classes (TglBitmap2D) instead.');
{$IFDEF GLB_NATIVE_OGL}
  glbReadOpenGLExtensions;
{$ENDIF}
  inherited Create;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aFileName: String);
begin
  Create;
  LoadFromFile(aFileName);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aStream: TStream);
begin
  Create;
  LoadFromStream(aStream);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aSize: TglBitmapPixelPosition; const aFormat: TglBitmapFormat);
var
  Image: PByte;
  ImageSize: Integer;
begin
  Create;
  ImageSize := TFormatDescriptor.Get(aFormat).GetSize(aSize);
  GetMem(Image, ImageSize);
  try
    FillChar(Image^, ImageSize, #$FF);
    SetDataPointer(Image, aFormat, aSize.X, aSize.Y); //be careful, Data could be freed by this method
  except
    if Assigned(Image) then
      FreeMem(Image);
    raise;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aSize: TglBitmapPixelPosition; const aFormat: TglBitmapFormat;
  const aFunc: TglBitmapFunction; const aArgs: Pointer);
begin
  Create;
  LoadFromFunc(aSize, aFunc, aFormat, aArgs);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aInstance: Cardinal; const aResource: String; const aResType: PChar);
begin
  Create;
  LoadFromResource(aInstance, aResource, aResType);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor TglBitmap.Create(const aInstance: Cardinal; const aResourceID: Integer; const aResType: PChar);
begin
  Create;
  LoadFromResourceID(aInstance, aResourceID, aResType);
end;

{$IFDEF GLB_SUPPORT_PNG_READ}
{$IF DEFINED(GLB_LAZ_PNG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//PNG/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadPNG(const aStream: TStream): Boolean;
const
  MAGIC_LEN = 8;
  PNG_MAGIC: String[MAGIC_LEN] = #$89#$50#$4E#$47#$0D#$0A#$1A#$0A;
var
  png: TPortableNetworkGraphic;
  intf: TLazIntfImage;
  StreamPos: Int64;
  magic: String[MAGIC_LEN];
begin
  result := true;
  StreamPos := aStream.Position;

  SetLength(magic, MAGIC_LEN);
  aStream.Read(magic[1], MAGIC_LEN);
  aStream.Position := StreamPos;
  if (magic <> PNG_MAGIC) then begin
    result := false;
    exit;
  end;

  png := TPortableNetworkGraphic.Create;
  try try
    png.LoadFromStream(aStream);
    intf := png.CreateIntfImage;
    try try
      AssignFromLazIntfImage(intf);
    except
      result := false;
      aStream.Position := StreamPos;
      exit;
    end;
    finally
      intf.Free;
    end;
  except
    result := false;
    aStream.Position := StreamPos;
    exit;
  end;
  finally
    png.Free;
  end;
end;

{$ELSEIF DEFINED(GLB_SDL_IMAGE)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadPNG(const aStream: TStream): Boolean;
var
  Surface: PSDL_Surface;
  RWops: PSDL_RWops;
begin
  result := false;
  RWops := glBitmapCreateRWops(aStream);
  try
    if IMG_isPNG(RWops) > 0 then begin
      Surface := IMG_LoadPNG_RW(RWops);
      try
        AssignFromSurface(Surface);
        result := true;
      finally
        SDL_FreeSurface(Surface);
      end;
    end;
  finally
    SDL_FreeRW(RWops);
  end;
end;

{$ELSEIF DEFINED(GLB_LIB_PNG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmap_libPNG_read_func(png: png_structp; buffer: png_bytep; size: cardinal); cdecl;
begin
  TStream(png_get_io_ptr(png)).Read(buffer^, size);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadPNG(const aStream: TStream): Boolean;
var
  StreamPos: Int64;
  signature: array [0..7] of byte;
  png: png_structp;
  png_info: png_infop;

  TempHeight, TempWidth: Integer;
  Format: TglBitmapFormat;

  png_data: pByte;
  png_rows: array of pByte;
  Row, LineSize: Integer;
begin
  result := false;

  if not init_libPNG then
    raise Exception.Create('LoadPNG - unable to initialize libPNG.');

  try
    // signature
    StreamPos := aStream.Position;
    aStream.Read(signature{%H-}, 8);
    aStream.Position := StreamPos;

    if png_check_sig(@signature, 8) <> 0 then begin
      // png read struct
      png := png_create_read_struct(PNG_LIBPNG_VER_STRING, nil, nil, nil);
      if png = nil then
        raise EglBitmapException.Create('LoadPng - couldn''t create read struct.');

      // png info
      png_info := png_create_info_struct(png);
      if png_info = nil then begin
        png_destroy_read_struct(@png, nil, nil);
        raise EglBitmapException.Create('LoadPng - couldn''t create info struct.');
      end;

      // set read callback
      png_set_read_fn(png, aStream, glBitmap_libPNG_read_func);

      // read informations
      png_read_info(png, png_info);

      // size
      TempHeight := png_get_image_height(png, png_info);
      TempWidth := png_get_image_width(png, png_info);

      // format
      case png_get_color_type(png, png_info) of
        PNG_COLOR_TYPE_GRAY:
          Format := tfLuminance8;
        PNG_COLOR_TYPE_GRAY_ALPHA:
          Format := tfLuminance8Alpha8;
        PNG_COLOR_TYPE_RGB:
          Format := tfRGB8;
        PNG_COLOR_TYPE_RGB_ALPHA:
          Format := tfRGBA8;
        else
          raise EglBitmapException.Create ('LoadPng - Unsupported Colortype found.');
      end;

      // cut upper 8 bit from 16 bit formats
      if png_get_bit_depth(png, png_info) > 8 then
        png_set_strip_16(png);

      // expand bitdepth smaller than 8
      if png_get_bit_depth(png, png_info) < 8 then
        png_set_expand(png);

      // allocating mem for scanlines
      LineSize := png_get_rowbytes(png, png_info);
      GetMem(png_data, TempHeight * LineSize);
      try
        SetLength(png_rows, TempHeight);
        for Row := Low(png_rows) to High(png_rows) do begin
          png_rows[Row] := png_data;
          Inc(png_rows[Row], Row * LineSize);
        end;

        // read complete image into scanlines
        png_read_image(png, @png_rows[0]);

        // read end
        png_read_end(png, png_info);

        // destroy read struct
        png_destroy_read_struct(@png, @png_info, nil);

        SetLength(png_rows, 0);

        // set new data
        SetDataPointer(png_data, Format, TempWidth, TempHeight); //be careful, Data could be freed by this method

        result := true;
      except
        if Assigned(png_data) then
          FreeMem(png_data);
        raise;
      end;
    end;
  finally
    quit_libPNG;
  end;
end;

{$ELSEIF DEFINED(GLB_PNGIMAGE)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadPNG(const aStream: TStream): Boolean;
var
  StreamPos: Int64;
  Png: TPNGObject;
  Header: String[8];
  Row, Col, PixSize, LineSize: Integer;
  NewImage, pSource, pDest, pAlpha: pByte;
  PngFormat: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;

const
  PngHeader: String[8] = #137#80#78#71#13#10#26#10;

begin
  result := false;

  StreamPos := aStream.Position;
  aStream.Read(Header[0], SizeOf(Header));
  aStream.Position := StreamPos;

  {Test if the header matches}
  if Header = PngHeader then begin
    Png := TPNGObject.Create;
    try
      Png.LoadFromStream(aStream);

      case Png.Header.ColorType of
        COLOR_GRAYSCALE:
          PngFormat := tfLuminance8;
        COLOR_GRAYSCALEALPHA:
          PngFormat := tfLuminance8Alpha8;
        COLOR_RGB:
          PngFormat := tfBGR8;
        COLOR_RGBALPHA:
          PngFormat := tfBGRA8;
        else
          raise EglBitmapException.Create ('LoadPng - Unsupported Colortype found.');
      end;

      FormatDesc := TFormatDescriptor.Get(PngFormat);
      PixSize    := Round(FormatDesc.PixelSize);
      LineSize   := FormatDesc.GetSize(Png.Header.Width, 1);

      GetMem(NewImage, LineSize * Integer(Png.Header.Height));
      try
        pDest := NewImage;

        case Png.Header.ColorType of
          COLOR_RGB, COLOR_GRAYSCALE:
            begin
              for Row := 0 to Png.Height -1 do begin
                Move (Png.Scanline[Row]^, pDest^, LineSize);
                Inc(pDest, LineSize);
              end;
            end;
          COLOR_RGBALPHA, COLOR_GRAYSCALEALPHA:
            begin
              PixSize := PixSize -1;

              for Row := 0 to Png.Height -1 do begin
                pSource := Png.Scanline[Row];
                pAlpha := pByte(Png.AlphaScanline[Row]);

                for Col := 0 to Png.Width -1 do begin
                  Move (pSource^, pDest^, PixSize);
                  Inc(pSource, PixSize);
                  Inc(pDest, PixSize);

                  pDest^ := pAlpha^;
                  inc(pAlpha);
                  Inc(pDest);
                end;
              end;
            end;
          else
            raise EglBitmapException.Create ('LoadPng - Unsupported Colortype found.');
        end;

        SetDataPointer(NewImage, PngFormat, Png.Header.Width, Png.Header.Height); //be careful, Data could be freed by this method

        result := true;
      except
        if Assigned(NewImage) then
          FreeMem(NewImage);
        raise;
      end;
    finally
      Png.Free;
    end;
  end;
end;
{$IFEND}
{$ENDIF}

{$IFDEF GLB_SUPPORT_PNG_WRITE}
{$IFDEF GLB_LIB_PNG}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmap_libPNG_write_func(png: png_structp; buffer: png_bytep; size: cardinal); cdecl;
begin
  TStream(png_get_io_ptr(png)).Write(buffer^, size);
end;
{$ENDIF}

{$IF DEFINED(GLB_LAZ_PNG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SavePNG(const aStream: TStream);
var
  png: TPortableNetworkGraphic;
  intf: TLazIntfImage;
begin
  png  := TPortableNetworkGraphic.Create;
  intf := TLazIntfImage.Create(0, 0);
  try
    if not AssignToLazIntfImage(intf) then
      raise EglBitmap.Create('unable to create LazIntfImage from glBitmap');
    png.LoadFromIntfImage(intf);
    png.SaveToStream(aStream);
  finally
    png.Free;
    intf.Free;
  end;
end;

{$ELSEIF DEFINED(GLB_LIB_PNG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SavePNG(const aStream: TStream);
var
  png: png_structp;
  png_info: png_infop;
  png_rows: array of pByte;
  LineSize: Integer;
  ColorType: Integer;
  Row: Integer;
  FormatDesc: TFormatDescriptor;
begin
  if not (ftPNG in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  if not init_libPNG then
    raise Exception.Create('unable to initialize libPNG.');

  try
    case Format of
      tfAlpha8, tfLuminance8:
        ColorType := PNG_COLOR_TYPE_GRAY;
      tfLuminance8Alpha8:
        ColorType := PNG_COLOR_TYPE_GRAY_ALPHA;
      tfBGR8, tfRGB8:
        ColorType := PNG_COLOR_TYPE_RGB;
      tfBGRA8, tfRGBA8:
        ColorType := PNG_COLOR_TYPE_RGBA;
      else
        raise EglBitmapUnsupportedFormat.Create(Format);
    end;

    FormatDesc := TFormatDescriptor.Get(Format);
    LineSize := FormatDesc.GetSize(Width, 1);

    // creating array for scanline
    SetLength(png_rows, Height);
    try
      for Row := 0 to Height - 1 do begin
        png_rows[Row] := Data;
        Inc(png_rows[Row], Row * LineSize)
      end;

      // write struct
      png := png_create_write_struct(PNG_LIBPNG_VER_STRING, nil, nil, nil);
      if png = nil then
        raise EglBitmapException.Create('SavePng - couldn''t create write struct.');

      // create png info
      png_info := png_create_info_struct(png);
      if png_info = nil then begin
        png_destroy_write_struct(@png, nil);
        raise EglBitmapException.Create('SavePng - couldn''t create info struct.');
      end;

      // set read callback
      png_set_write_fn(png, aStream, glBitmap_libPNG_write_func, nil);

      // set compression
      png_set_compression_level(png, 6);

      if Format in [tfBGR8, tfBGRA8] then
        png_set_bgr(png);

      png_set_IHDR(png, png_info, Width, Height, 8, ColorType, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
      png_write_info(png, png_info);
      png_write_image(png, @png_rows[0]);
      png_write_end(png, png_info);
      png_destroy_write_struct(@png, @png_info);
    finally
      SetLength(png_rows, 0);
    end;
  finally
    quit_libPNG;
  end;
end;

{$ELSEIF DEFINED(GLB_PNGIMAGE)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SavePNG(const aStream: TStream);
var
  Png: TPNGObject;

  pSource, pDest: pByte;
  X, Y, PixSize: Integer;
  ColorType: Cardinal;
  Alpha: Boolean;

  pTemp: pByte;
  Temp: Byte;
begin
  if not (ftPNG in FormatGetSupportedFiles (Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  case Format of
    tfAlpha8, tfLuminance8: begin
      ColorType := COLOR_GRAYSCALE;
      PixSize   := 1;
      Alpha     := false;
    end;
    tfLuminance8Alpha8: begin
      ColorType := COLOR_GRAYSCALEALPHA;
      PixSize   := 1;
      Alpha     := true;
    end;
    tfBGR8, tfRGB8: begin
      ColorType := COLOR_RGB;
      PixSize   := 3;
      Alpha     := false;
    end;
    tfBGRA8, tfRGBA8: begin
      ColorType := COLOR_RGBALPHA;
      PixSize   := 3;
      Alpha     := true
    end;
  else
    raise EglBitmapUnsupportedFormat.Create(Format);
  end;

  Png := TPNGObject.CreateBlank(ColorType, 8, Width, Height);
  try
    // Copy ImageData
    pSource := Data;
    for Y := 0 to Height -1 do begin
      pDest := png.ScanLine[Y];
      for X := 0 to Width -1 do begin
        Move(pSource^, pDest^, PixSize);
        Inc(pDest, PixSize);
        Inc(pSource, PixSize);
        if Alpha then begin
          png.AlphaScanline[Y]^[X] := pSource^;
          Inc(pSource);
        end;
      end;

      // convert RGB line to BGR
      if Format in [tfRGB8, tfRGBA8] then begin
        pTemp := png.ScanLine[Y];
        for X := 0 to Width -1 do begin
          Temp := pByteArray(pTemp)^[0];
          pByteArray(pTemp)^[0] := pByteArray(pTemp)^[2];
          pByteArray(pTemp)^[2] := Temp;
          Inc(pTemp, 3);
        end;
      end;
    end;

    // Save to Stream
    Png.CompressionLevel := 6;
    Png.SaveToStream(aStream);
  finally
    FreeAndNil(Png);
  end;
end;
{$IFEND}
{$ENDIF}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//JPEG////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
{$IFDEF GLB_LIB_JPEG}
type
  glBitmap_libJPEG_source_mgr_ptr = ^glBitmap_libJPEG_source_mgr;
  glBitmap_libJPEG_source_mgr = record
    pub: jpeg_source_mgr;

    SrcStream: TStream;
    SrcBuffer: array [1..4096] of byte;
  end;

  glBitmap_libJPEG_dest_mgr_ptr = ^glBitmap_libJPEG_dest_mgr;
  glBitmap_libJPEG_dest_mgr = record
    pub: jpeg_destination_mgr;

    DestStream: TStream;
    DestBuffer: array [1..4096] of byte;
  end;

procedure glBitmap_libJPEG_error_exit(cinfo: j_common_ptr); cdecl;
begin
  //DUMMY
end;


procedure glBitmap_libJPEG_output_message(cinfo: j_common_ptr); cdecl;
begin
  //DUMMY
end;


procedure glBitmap_libJPEG_init_source(cinfo: j_decompress_ptr); cdecl;
begin
  //DUMMY
end;

procedure glBitmap_libJPEG_term_source(cinfo: j_decompress_ptr); cdecl;
begin
  //DUMMY
end;


procedure glBitmap_libJPEG_init_destination(cinfo: j_compress_ptr); cdecl;
begin
  //DUMMY
end;


//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmap_libJPEG_fill_input_buffer(cinfo: j_decompress_ptr): boolean; cdecl;
var
  src: glBitmap_libJPEG_source_mgr_ptr;
  bytes: integer;
begin
  src := glBitmap_libJPEG_source_mgr_ptr(cinfo^.src);

  bytes := src^.SrcStream.Read(src^.SrcBuffer[1], 4096);
	if (bytes <= 0) then begin
		src^.SrcBuffer[1] := $FF;
		src^.SrcBuffer[2] := JPEG_EOI;
		bytes := 2;
	end;

	src^.pub.next_input_byte := @(src^.SrcBuffer[1]);
	src^.pub.bytes_in_buffer := bytes;

  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmap_libJPEG_skip_input_data(cinfo: j_decompress_ptr; num_bytes: Longint); cdecl;
var
  src: glBitmap_libJPEG_source_mgr_ptr;
begin
  src := glBitmap_libJPEG_source_mgr_ptr(cinfo^.src);

  if num_bytes > 0 then begin
    // wanted byte isn't in buffer so set stream position and read buffer
    if num_bytes > src^.pub.bytes_in_buffer then begin
      src^.SrcStream.Position := src^.SrcStream.Position + num_bytes - src^.pub.bytes_in_buffer;
      src^.pub.fill_input_buffer(cinfo);
    end else begin
      // wanted byte is in buffer so only skip
  		inc(src^.pub.next_input_byte, num_bytes);
	  	dec(src^.pub.bytes_in_buffer, num_bytes);
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function glBitmap_libJPEG_empty_output_buffer(cinfo: j_compress_ptr): boolean; cdecl;
var
  dest: glBitmap_libJPEG_dest_mgr_ptr;
begin
  dest := glBitmap_libJPEG_dest_mgr_ptr(cinfo^.dest);

  if dest^.pub.free_in_buffer < Cardinal(Length(dest^.DestBuffer)) then begin
    // write complete buffer
    dest^.DestStream.Write(dest^.DestBuffer[1], SizeOf(dest^.DestBuffer));

    // reset buffer
    dest^.pub.next_output_byte := @dest^.DestBuffer[1];
    dest^.pub.free_in_buffer := Length(dest^.DestBuffer);
  end;

  result := true;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmap_libJPEG_term_destination(cinfo: j_compress_ptr); cdecl;
var
  Idx: Integer;
  dest: glBitmap_libJPEG_dest_mgr_ptr;
begin
  dest := glBitmap_libJPEG_dest_mgr_ptr(cinfo^.dest);

  for Idx := Low(dest^.DestBuffer) to High(dest^.DestBuffer) do begin
    // check for endblock
    if (Idx < High(dest^.DestBuffer)) and (dest^.DestBuffer[Idx] = $FF) and (dest^.DestBuffer[Idx +1] = JPEG_EOI) then begin
      // write endblock
      dest^.DestStream.Write(dest^.DestBuffer[Idx], 2);

      // leave
      break;
    end else
      dest^.DestStream.Write(dest^.DestBuffer[Idx], 1);
  end;
end;
{$ENDIF}

{$IFDEF GLB_SUPPORT_JPEG_READ}
{$IF DEFINED(GLB_LAZ_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadJPEG(const aStream: TStream): Boolean;
const
  MAGIC_LEN = 2;
  JPEG_MAGIC: String[MAGIC_LEN] = #$FF#$D8;
var
  jpeg: TJPEGImage;
  intf: TLazIntfImage;
  StreamPos: Int64;
  magic: String[MAGIC_LEN];
begin
  result := true;
  StreamPos := aStream.Position;

  SetLength(magic, MAGIC_LEN);
  aStream.Read(magic[1], MAGIC_LEN);
  aStream.Position := StreamPos;
  if (magic <> JPEG_MAGIC) then begin
    result := false;
    exit;
  end;

  jpeg := TJPEGImage.Create;
  try try
    jpeg.LoadFromStream(aStream);
    intf := TLazIntfImage.Create(0, 0);
    try try
      intf.LoadFromBitmap(jpeg.BitmapHandle, jpeg.MaskHandle);
      AssignFromLazIntfImage(intf);
    except
      result := false;
      aStream.Position := StreamPos;
      exit;
    end;
    finally
      intf.Free;
    end;
  except
    result := false;
    aStream.Position := StreamPos;
    exit;
  end;
  finally
    jpeg.Free;
  end;
end;

{$ELSEIF DEFINED(GLB_SDL_IMAGE)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadJPEG(const aStream: TStream): Boolean;
var
  Surface: PSDL_Surface;
  RWops: PSDL_RWops;
begin
  result := false;

  RWops := glBitmapCreateRWops(aStream);
  try
    if IMG_isJPG(RWops) > 0 then begin
      Surface := IMG_LoadJPG_RW(RWops);
      try
        AssignFromSurface(Surface);
        result := true;
      finally
        SDL_FreeSurface(Surface);
      end;
    end;
  finally
    SDL_FreeRW(RWops);
  end;
end;

{$ELSEIF DEFINED(GLB_LIB_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadJPEG(const aStream: TStream): Boolean;
var
  StreamPos: Int64;
  Temp: array[0..1]of Byte;

  jpeg: jpeg_decompress_struct;
  jpeg_err: jpeg_error_mgr;

  IntFormat: TglBitmapFormat;
  pImage: pByte;
  TempHeight, TempWidth: Integer;

  pTemp: pByte;
  Row: Integer;

  FormatDesc: TFormatDescriptor;
begin
  result := false;

  if not init_libJPEG then
    raise Exception.Create('LoadJPG - unable to initialize libJPEG.');

  try
    // reading first two bytes to test file and set cursor back to begin
    StreamPos := aStream.Position;
    aStream.Read({%H-}Temp[0], 2);
    aStream.Position := StreamPos;

    // if Bitmap then read file.
    if ((Temp[0] = $FF) and (Temp[1] = $D8)) then begin
      FillChar(jpeg{%H-}, SizeOf(jpeg_decompress_struct), $00);
      FillChar(jpeg_err{%H-}, SizeOf(jpeg_error_mgr), $00);

      // error managment
      jpeg.err := jpeg_std_error(@jpeg_err);
      jpeg_err.error_exit     := glBitmap_libJPEG_error_exit;
      jpeg_err.output_message := glBitmap_libJPEG_output_message;

      // decompression struct
      jpeg_create_decompress(@jpeg);

      // allocation space for streaming methods
      jpeg.src := jpeg.mem^.alloc_small(@jpeg, JPOOL_PERMANENT, SizeOf(glBitmap_libJPEG_source_mgr));

      // seeting up custom functions
      with glBitmap_libJPEG_source_mgr_ptr(jpeg.src)^ do begin
        pub.init_source       := glBitmap_libJPEG_init_source;
        pub.fill_input_buffer := glBitmap_libJPEG_fill_input_buffer;
        pub.skip_input_data   := glBitmap_libJPEG_skip_input_data;
        pub.resync_to_restart := jpeg_resync_to_restart; // use default method
        pub.term_source       := glBitmap_libJPEG_term_source;

        pub.bytes_in_buffer := 0;     // forces fill_input_buffer on first read
        pub.next_input_byte := nil;   // until buffer loaded

        SrcStream := aStream;
      end;

      // set global decoding state
      jpeg.global_state := DSTATE_START;

      // read header of jpeg
      jpeg_read_header(@jpeg, false);

      // setting output parameter
      case jpeg.jpeg_color_space of
        JCS_GRAYSCALE:
          begin
            jpeg.out_color_space := JCS_GRAYSCALE;
            IntFormat := tfLuminance8;
          end;
        else
          jpeg.out_color_space := JCS_RGB;
          IntFormat := tfRGB8;
      end;

      // reading image
      jpeg_start_decompress(@jpeg);

      TempHeight := jpeg.output_height;
      TempWidth := jpeg.output_width;

      FormatDesc := TFormatDescriptor.Get(IntFormat);

      // creating new image
      GetMem(pImage, FormatDesc.GetSize(TempWidth, TempHeight));
      try
        pTemp := pImage;

        for Row := 0 to TempHeight -1 do begin
          jpeg_read_scanlines(@jpeg, @pTemp, 1);
          Inc(pTemp, FormatDesc.GetSize(TempWidth, 1));
        end;

        // finish decompression
        jpeg_finish_decompress(@jpeg);

        // destroy decompression
        jpeg_destroy_decompress(@jpeg);

        SetDataPointer(pImage, IntFormat, TempWidth, TempHeight); //be careful, Data could be freed by this method

        result := true;
      except
        if Assigned(pImage) then
          FreeMem(pImage);
        raise;
      end;
    end;
  finally
    quit_libJPEG;
  end;
end;

{$ELSEIF DEFINED(GLB_DELPHI_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadJPEG(const aStream: TStream): Boolean;
var
  bmp: TBitmap;
  jpg: TJPEGImage;
  StreamPos: Int64;
  Temp: array[0..1]of Byte;
begin
  result := false;

  // reading first two bytes to test file and set cursor back to begin
  StreamPos := aStream.Position;
  aStream.Read(Temp[0], 2);
  aStream.Position := StreamPos;

  // if Bitmap then read file.
  if ((Temp[0] = $FF) and (Temp[1] = $D8)) then begin
    bmp := TBitmap.Create;
    try
      jpg := TJPEGImage.Create;
      try
        jpg.LoadFromStream(aStream);
        bmp.Assign(jpg);
        result := AssignFromBitmap(bmp);
      finally
        jpg.Free;
      end;
    finally
      bmp.Free;
    end;
  end;
end;
{$IFEND}
{$ENDIF}

{$IFDEF GLB_SUPPORT_JPEG_WRITE}
{$IF DEFINED(GLB_LAZ_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveJPEG(const aStream: TStream);
var
  jpeg: TJPEGImage;
  intf: TLazIntfImage;
begin
  jpeg := TJPEGImage.Create;
  intf := TLazIntfImage.Create(0, 0);
  try
    if not AssignToLazIntfImage(intf) then
      raise EglBitmap.Create('unable to create LazIntfImage from glBitmap');
    jpeg.LoadFromIntfImage(intf);
    jpeg.SaveToStream(aStream);
  finally
    intf.Free;
    jpeg.Free;
  end;
end;

{$ELSEIF DEFINED(GLB_LIB_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveJPEG(const aStream: TStream);
var
  jpeg: jpeg_compress_struct;
  jpeg_err: jpeg_error_mgr;
  Row: Integer;
  pTemp, pTemp2: pByte;

  procedure CopyRow(pDest, pSource: pByte);
  var
    X: Integer;
  begin
    for X := 0 to Width - 1 do begin
      pByteArray(pDest)^[0] := pByteArray(pSource)^[2];
      pByteArray(pDest)^[1] := pByteArray(pSource)^[1];
      pByteArray(pDest)^[2] := pByteArray(pSource)^[0];
      Inc(pDest, 3);
      Inc(pSource, 3);
    end;
  end;

begin
  if not (ftJPEG in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  if not init_libJPEG then
    raise Exception.Create('SaveJPG - unable to initialize libJPEG.');

  try
    FillChar(jpeg{%H-}, SizeOf(jpeg_compress_struct), $00);
    FillChar(jpeg_err{%H-}, SizeOf(jpeg_error_mgr), $00);

    // error managment
    jpeg.err := jpeg_std_error(@jpeg_err);
    jpeg_err.error_exit     := glBitmap_libJPEG_error_exit;
    jpeg_err.output_message := glBitmap_libJPEG_output_message;

    // compression struct
    jpeg_create_compress(@jpeg);

    // allocation space for streaming methods
    jpeg.dest := jpeg.mem^.alloc_small(@jpeg, JPOOL_PERMANENT, SizeOf(glBitmap_libJPEG_dest_mgr));

    // seeting up custom functions
    with glBitmap_libJPEG_dest_mgr_ptr(jpeg.dest)^ do begin
      pub.init_destination    := glBitmap_libJPEG_init_destination;
      pub.empty_output_buffer := glBitmap_libJPEG_empty_output_buffer;
      pub.term_destination    := glBitmap_libJPEG_term_destination;

      pub.next_output_byte  := @DestBuffer[1];
      pub.free_in_buffer    := Length(DestBuffer);

      DestStream := aStream;
    end;

    // very important state
    jpeg.global_state := CSTATE_START;
    jpeg.image_width  := Width;
    jpeg.image_height := Height;
    case Format of
      tfAlpha8, tfLuminance8: begin
        jpeg.input_components := 1;
        jpeg.in_color_space   := JCS_GRAYSCALE;
      end;
      tfRGB8, tfBGR8: begin
        jpeg.input_components := 3;
        jpeg.in_color_space   := JCS_RGB;
      end;
    end;

    jpeg_set_defaults(@jpeg);
    jpeg_set_quality(@jpeg, 95, true);
    jpeg_start_compress(@jpeg, true);
    pTemp := Data;

    if Format = tfBGR8 then
      GetMem(pTemp2, fRowSize)
    else
      pTemp2 := pTemp;

    try
      for Row := 0 to jpeg.image_height -1 do begin
        // prepare row
        if Format = tfBGR8 then
          CopyRow(pTemp2, pTemp)
        else
          pTemp2 := pTemp;

        // write row
        jpeg_write_scanlines(@jpeg, @pTemp2, 1);
        inc(pTemp, fRowSize);
      end;
    finally
      // free memory
      if Format = tfBGR8 then
        FreeMem(pTemp2);
    end;
    jpeg_finish_compress(@jpeg);
    jpeg_destroy_compress(@jpeg);
  finally
    quit_libJPEG;
  end;
end;

{$ELSEIF DEFINED(GLB_DELPHI_JPEG)}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveJPEG(const aStream: TStream);
var
  Bmp: TBitmap;
  Jpg: TJPEGImage;
begin
  if not (ftJPEG in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  Bmp := TBitmap.Create;
  try
    Jpg := TJPEGImage.Create;
    try
      AssignToBitmap(Bmp);
      if (Format in [tfAlpha8, tfLuminance8]) then begin
        Jpg.Grayscale   := true;
        Jpg.PixelFormat := jf8Bit;
      end;
      Jpg.Assign(Bmp);
      Jpg.SaveToStream(aStream);
    finally
      FreeAndNil(Jpg);
    end;
  finally
    FreeAndNil(Bmp);
  end;
end;
{$IFEND}
{$ENDIF}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//BMP/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
const
  BMP_MAGIC          = $4D42;

  BMP_COMP_RGB       = 0;
  BMP_COMP_RLE8      = 1;
  BMP_COMP_RLE4      = 2;
  BMP_COMP_BITFIELDS = 3;

type
  TBMPHeader = packed record
    bfType: Word;
    bfSize: Cardinal;
    bfReserved1: Word;
    bfReserved2: Word;
    bfOffBits: Cardinal;
  end;

  TBMPInfo = packed record
    biSize: Cardinal;
    biWidth: Longint;
    biHeight: Longint;
    biPlanes: Word;
    biBitCount: Word;
    biCompression: Cardinal;
    biSizeImage: Cardinal;
    biXPelsPerMeter: Longint;
    biYPelsPerMeter: Longint;
    biClrUsed: Cardinal;
    biClrImportant: Cardinal;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadBMP(const aStream: TStream): Boolean;

  //////////////////////////////////////////////////////////////////////////////////////////////////
  function ReadInfo(out aInfo: TBMPInfo; out aMask: TglBitmapColorRec): TglBitmapFormat;
  begin
    result := tfEmpty;
    aStream.Read(aInfo{%H-}, SizeOf(aInfo));
    FillChar(aMask{%H-}, SizeOf(aMask), 0);

    //Read Compression
    case aInfo.biCompression of
      BMP_COMP_RLE4,
      BMP_COMP_RLE8: begin
        raise EglBitmap.Create('RLE compression is not supported');
      end;
      BMP_COMP_BITFIELDS: begin
        if (aInfo.biBitCount = 16) or (aInfo.biBitCount = 32) then begin
          aStream.Read(aMask.r, SizeOf(aMask.r));
          aStream.Read(aMask.g, SizeOf(aMask.g));
          aStream.Read(aMask.b, SizeOf(aMask.b));
          aStream.Read(aMask.a, SizeOf(aMask.a));
        end else
          raise EglBitmap.Create('Bitfields are only supported for 16bit and 32bit formats');
      end;
    end;

    //get suitable format
    case aInfo.biBitCount of
       8: result := tfLuminance8;
      16: result := tfBGR5;
      24: result := tfBGR8;
      32: result := tfBGRA8;
    end;
  end;

  function ReadColorTable(var aFormat: TglBitmapFormat; const aInfo: TBMPInfo): TbmpColorTableFormat;
  var
    i, c: Integer;
    ColorTable: TbmpColorTable;
  begin
    result := nil;
    if (aInfo.biBitCount >= 16) then
      exit;
    aFormat := tfLuminance8;
    c := aInfo.biClrUsed;
    if (c = 0) then
      c := 1 shl aInfo.biBitCount;
    SetLength(ColorTable, c);
    for i := 0 to c-1 do begin
      aStream.Read(ColorTable[i], SizeOf(TbmpColorTableEnty));
      if (ColorTable[i].r <> ColorTable[i].g) or (ColorTable[i].g <> ColorTable[i].b) then
        aFormat := tfRGB8;
    end;

    result := TbmpColorTableFormat.Create;
    result.PixelSize  := aInfo.biBitCount / 8;
    result.ColorTable := ColorTable;
    result.Range      := glBitmapColorRec($FF, $FF, $FF, $00);
  end;

  //////////////////////////////////////////////////////////////////////////////////////////////////
  function CheckBitfields(var aFormat: TglBitmapFormat; const aMask: TglBitmapColorRec;
    const aInfo: TBMPInfo): TbmpBitfieldFormat;
  var
    TmpFormat: TglBitmapFormat;
    FormatDesc: TFormatDescriptor;
  begin
    result := nil;
    if (aMask.r <> 0) or (aMask.g <> 0) or (aMask.b <> 0) or (aMask.a <> 0) then begin
      for TmpFormat := High(TglBitmapFormat) downto Low(TglBitmapFormat) do begin
        FormatDesc := TFormatDescriptor.Get(TmpFormat);
        if FormatDesc.MaskMatch(aMask.r, aMask.g, aMask.b, aMask.a) then begin
          aFormat := FormatDesc.Format;
          exit;
        end;
      end;

      if (aMask.a = 0) and TFormatDescriptor.Get(aFormat).HasAlpha then
        aFormat := TFormatDescriptor.Get(aFormat).WithoutAlpha;
      if (aMask.a <> 0) and not TFormatDescriptor.Get(aFormat).HasAlpha then
        aFormat := TFormatDescriptor.Get(aFormat).WithAlpha;

      result := TbmpBitfieldFormat.Create;
      result.PixelSize := aInfo.biBitCount / 8;
      result.RedMask   := aMask.r;
      result.GreenMask := aMask.g;
      result.BlueMask  := aMask.b;
      result.AlphaMask := aMask.a;
    end;
  end;

var
  //simple types
  StartPos: Int64;
  ImageSize, rbLineSize, wbLineSize, Padding, i: Integer;
  PaddingBuff: Cardinal;
  LineBuf, ImageData, TmpData: PByte;
  SourceMD, DestMD: Pointer;
  BmpFormat: TglBitmapFormat;

  //records
  Mask: TglBitmapColorRec;
  Header: TBMPHeader;
  Info: TBMPInfo;

  //classes
  SpecialFormat: TFormatDescriptor;
  FormatDesc: TFormatDescriptor;

  //////////////////////////////////////////////////////////////////////////////////////////////////
  procedure SpecialFormatReadLine(aData: PByte; aLineBuf: PByte);
  var
    i: Integer;
    Pixel: TglBitmapPixelData;
  begin
    aStream.Read(aLineBuf^, rbLineSize);
    SpecialFormat.PreparePixel(Pixel);
    for i := 0 to Info.biWidth-1 do begin
      SpecialFormat.Unmap(aLineBuf, Pixel, SourceMD);
      glBitmapConvertPixel(Pixel, SpecialFormat, FormatDesc);
      FormatDesc.Map(Pixel, aData, DestMD);
    end;
  end;

begin
  result        := false;
  BmpFormat     := tfEmpty;
  SpecialFormat := nil;
  LineBuf       := nil;
  SourceMD      := nil;
  DestMD        := nil;

  // Header
  StartPos := aStream.Position;
  aStream.Read(Header{%H-}, SizeOf(Header));

  if Header.bfType = BMP_MAGIC then begin
    try try
      BmpFormat        := ReadInfo(Info, Mask);
      SpecialFormat    := ReadColorTable(BmpFormat, Info);
      if not Assigned(SpecialFormat) then
        SpecialFormat  := CheckBitfields(BmpFormat, Mask, Info);
      aStream.Position := StartPos + Header.bfOffBits;

      if (BmpFormat <> tfEmpty) then begin
        FormatDesc := TFormatDescriptor.Get(BmpFormat);
        rbLineSize := Round(Info.biWidth * Info.biBitCount / 8); //ReadBuffer LineSize
        wbLineSize := Trunc(Info.biWidth * FormatDesc.PixelSize);
        Padding    := (((Info.biWidth * Info.biBitCount + 31) and - 32) shr 3) - rbLineSize;

        //get Memory
        DestMD    := FormatDesc.CreateMappingData;
        ImageSize := FormatDesc.GetSize(Info.biWidth, abs(Info.biHeight));
        GetMem(ImageData, ImageSize);
        if Assigned(SpecialFormat) then begin
          GetMem(LineBuf, rbLineSize); //tmp Memory for converting Bitfields
          SourceMD := SpecialFormat.CreateMappingData;
        end;

        //read Data
        try try
          FillChar(ImageData^, ImageSize, $FF);
          TmpData := ImageData;
          if (Info.biHeight > 0) then
            Inc(TmpData, wbLineSize * (Info.biHeight-1));
          for i := 0 to Abs(Info.biHeight)-1 do begin
            if Assigned(SpecialFormat) then
              SpecialFormatReadLine(TmpData, LineBuf)  //if is special format read and convert data
            else
              aStream.Read(TmpData^, wbLineSize);   //else only read data
            if (Info.biHeight > 0) then
              dec(TmpData, wbLineSize)
            else
              inc(TmpData, wbLineSize);
            aStream.Read(PaddingBuff{%H-}, Padding);
          end;
          SetDataPointer(ImageData, BmpFormat, Info.biWidth, abs(Info.biHeight)); //be careful, Data could be freed by this method
          result := true;
        finally
          if Assigned(LineBuf) then
            FreeMem(LineBuf);
          if Assigned(SourceMD) then
            SpecialFormat.FreeMappingData(SourceMD);
          FormatDesc.FreeMappingData(DestMD);
        end;
        except
          if Assigned(ImageData) then
            FreeMem(ImageData);
          raise;
        end;
      end else
        raise EglBitmap.Create('LoadBMP - No suitable format found');
    except
      aStream.Position := StartPos;
      raise;
    end;
    finally
      FreeAndNil(SpecialFormat);
    end;
  end
    else aStream.Position := StartPos;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveBMP(const aStream: TStream);
var
  Header: TBMPHeader;
  Info: TBMPInfo;
  Converter: TFormatDescriptor;
  FormatDesc: TFormatDescriptor;
  SourceFD, DestFD: Pointer;
  pData, srcData, dstData, ConvertBuffer: pByte;

  Pixel: TglBitmapPixelData;
  ImageSize, wbLineSize, rbLineSize, Padding, LineIdx, PixelIdx: Integer;
  RedMask, GreenMask, BlueMask, AlphaMask: Cardinal;

  PaddingBuff: Cardinal;

  function GetLineWidth : Integer;
  begin
    result := ((Info.biWidth * Info.biBitCount + 31) and - 32) shr 3;
  end;

begin
  if not (ftBMP in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  Converter  := nil;
  FormatDesc := TFormatDescriptor.Get(Format);
  ImageSize  := FormatDesc.GetSize(Dimension);

  FillChar(Header{%H-}, SizeOf(Header), 0);
  Header.bfType      := BMP_MAGIC;
  Header.bfSize      := SizeOf(Header) + SizeOf(Info) + ImageSize;
  Header.bfReserved1 := 0;
  Header.bfReserved2 := 0;
  Header.bfOffBits   := SizeOf(Header) + SizeOf(Info);

  FillChar(Info{%H-}, SizeOf(Info), 0);
  Info.biSize        := SizeOf(Info);
  Info.biWidth       := Width;
  Info.biHeight      := Height;
  Info.biPlanes      := 1;
  Info.biCompression := BMP_COMP_RGB;
  Info.biSizeImage   := ImageSize;

  try
    case Format of
      tfLuminance4: begin
        Info.biBitCount  := 4;
        Header.bfSize    := Header.bfSize    + 16 * SizeOf(Cardinal);
        Header.bfOffBits := Header.bfOffBits + 16 * SizeOf(Cardinal); //16 ColorTable entries
        Converter := TbmpColorTableFormat.Create;
        with (Converter as TbmpColorTableFormat) do begin
          PixelSize := 0.5;
          Format    := Format;
          Range     := glBitmapColorRec($F, $F, $F, $0);
          CreateColorTable;
        end;
      end;

      tfR3G3B2, tfLuminance8: begin
        Info.biBitCount  :=  8;
        Header.bfSize    := Header.bfSize    + 256 * SizeOf(Cardinal);
        Header.bfOffBits := Header.bfOffBits + 256 * SizeOf(Cardinal); //256 ColorTable entries
        Converter := TbmpColorTableFormat.Create;
        with (Converter as TbmpColorTableFormat) do begin
          PixelSize := 1;
          Format    := Format;
          if (Format = tfR3G3B2) then begin
            Range := glBitmapColorRec($7, $7, $3, $0);
            Shift := glBitmapShiftRec(0, 3, 6, 0);
          end else
            Range := glBitmapColorRec($FF, $FF, $FF, $0);
          CreateColorTable;
        end;
      end;

      tfRGB4, tfRGB5, tfR5G6B5, tfRGB5A1, tfRGBA4,
      tfBGR4, tfBGR5, tfB5G6R5, tfBGR5A1, tfBGRA4: begin
        Info.biBitCount    := 16;
        Info.biCompression := BMP_COMP_BITFIELDS;
      end;

      tfBGR8, tfRGB8: begin
        Info.biBitCount := 24;
        if (Format = tfRGB8) then
          Converter := TfdBGR8.Create; //use BGR8 Format Descriptor to Swap RGB Values
      end;

      tfRGB10, tfRGB10A2, tfRGBA8,
      tfBGR10, tfBGR10A2, tfBGRA8: begin
        Info.biBitCount    := 32;
        Info.biCompression := BMP_COMP_BITFIELDS;
      end;
    else
      raise EglBitmapUnsupportedFormat.Create(Format);
    end;
    Info.biXPelsPerMeter := 2835;
    Info.biYPelsPerMeter := 2835;

    // prepare bitmasks
    if Info.biCompression = BMP_COMP_BITFIELDS then begin
      Header.bfSize    := Header.bfSize    + 4 * SizeOf(Cardinal);
      Header.bfOffBits := Header.bfOffBits + 4 * SizeOf(Cardinal);

      RedMask    := FormatDesc.RedMask;
      GreenMask  := FormatDesc.GreenMask;
      BlueMask   := FormatDesc.BlueMask;
      AlphaMask  := FormatDesc.AlphaMask;
    end;

    // headers
    aStream.Write(Header, SizeOf(Header));
    aStream.Write(Info, SizeOf(Info));

    // colortable
    if Assigned(Converter) and (Converter is TbmpColorTableFormat) then
      with (Converter as TbmpColorTableFormat) do
        aStream.Write(ColorTable[0].b,
          SizeOf(TbmpColorTableEnty) * Length(ColorTable));

    // bitmasks
    if Info.biCompression = BMP_COMP_BITFIELDS then begin
      aStream.Write(RedMask,   SizeOf(Cardinal));
      aStream.Write(GreenMask, SizeOf(Cardinal));
      aStream.Write(BlueMask,  SizeOf(Cardinal));
      aStream.Write(AlphaMask, SizeOf(Cardinal));
    end;

    // image data
    rbLineSize  := Round(Info.biWidth * FormatDesc.PixelSize);
    wbLineSize  := Round(Info.biWidth * Info.biBitCount / 8);
    Padding     := GetLineWidth - wbLineSize;
    PaddingBuff := 0;

    pData := Data;
    inc(pData, (Height-1) * rbLineSize);

    // prepare row buffer. But only for RGB because RGBA supports color masks
    // so it's possible to change color within the image.
    if Assigned(Converter) then begin
      FormatDesc.PreparePixel(Pixel);
      GetMem(ConvertBuffer, wbLineSize);
      SourceFD := FormatDesc.CreateMappingData;
      DestFD   := Converter.CreateMappingData;
    end else
      ConvertBuffer := nil;

    try
      for LineIdx := 0 to Height - 1 do begin
        // preparing row
        if Assigned(Converter) then begin
          srcData := pData;
          dstData := ConvertBuffer;
          for PixelIdx := 0 to Info.biWidth-1 do begin
            FormatDesc.Unmap(srcData, Pixel, SourceFD);
            glBitmapConvertPixel(Pixel, FormatDesc, Converter);
            Converter.Map(Pixel, dstData, DestFD);
          end;
          aStream.Write(ConvertBuffer^, wbLineSize);
        end else begin
          aStream.Write(pData^, rbLineSize);
        end;
        dec(pData, rbLineSize);
        if (Padding > 0) then
          aStream.Write(PaddingBuff, Padding);
      end;
    finally
      // destroy row buffer
      if Assigned(ConvertBuffer) then begin
        FormatDesc.FreeMappingData(SourceFD);
        Converter.FreeMappingData(DestFD);
        FreeMem(ConvertBuffer);
      end;
    end;
  finally
    if Assigned(Converter) then
      Converter.Free;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TGA/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
type
  TTGAHeader = packed record
    ImageID: Byte;
    ColorMapType: Byte;
    ImageType: Byte;
    //ColorMapSpec: Array[0..4] of Byte;
    ColorMapStart: Word;
    ColorMapLength: Word;
    ColorMapEntrySize: Byte;
    OrigX: Word;
    OrigY: Word;
    Width: Word;
    Height: Word;
    Bpp: Byte;
    ImageDesc: Byte;
  end;

const
  TGA_UNCOMPRESSED_RGB  =  2;
  TGA_UNCOMPRESSED_GRAY =  3;
  TGA_COMPRESSED_RGB    = 10;
  TGA_COMPRESSED_GRAY   = 11;

  TGA_NONE_COLOR_TABLE  = 0;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadTGA(const aStream: TStream): Boolean;
var
  Header: TTGAHeader;
  ImageData: System.PByte;
  StartPosition: Int64;
  PixelSize, LineSize: Integer;
  tgaFormat: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;
  Counter: packed record
    X, Y: packed record
      low, high, dir: Integer;
    end;
  end;

const
  CACHE_SIZE = $4000;

  ////////////////////////////////////////////////////////////////////////////////////////
  procedure ReadUncompressed;
  var
    i, j: Integer;
    buf, tmp1, tmp2: System.PByte;
  begin
    buf := nil;
    if (Counter.X.dir < 0) then
      GetMem(buf, LineSize);
    try
      while (Counter.Y.low <> Counter.Y.high + counter.Y.dir) do begin
        tmp1 := ImageData;
        inc(tmp1, (Counter.Y.low * LineSize));          //pointer to LineStart
        if (Counter.X.dir < 0) then begin               //flip X
          aStream.Read(buf^, LineSize);
          tmp2 := buf;
          inc(tmp2, LineSize - PixelSize);              //pointer to last pixel in line
          for i := 0 to Header.Width-1 do begin         //for all pixels in line
            for j := 0 to PixelSize-1 do begin          //for all bytes in pixel
              tmp1^ := tmp2^;
              inc(tmp1);
              inc(tmp2);
            end;
            dec(tmp2, 2*PixelSize);                     //move 2 backwards, because j-loop moved 1 forward
          end;
        end else
          aStream.Read(tmp1^, LineSize);
        inc(Counter.Y.low, Counter.Y.dir);              //move to next line index
      end;
    finally
      if Assigned(buf) then
        FreeMem(buf);
    end;
  end;

  ////////////////////////////////////////////////////////////////////////////////////////
  procedure ReadCompressed;

    /////////////////////////////////////////////////////////////////
    var
      TmpData: System.PByte;
      LinePixelsRead: Integer;
    procedure CheckLine;
    begin
      if (LinePixelsRead >= Header.Width) then begin
        LinePixelsRead := 0;
        inc(Counter.Y.low, Counter.Y.dir);                //next line index
        TmpData := ImageData;
        inc(TmpData, Counter.Y.low * LineSize);           //set line
        if (Counter.X.dir < 0) then                       //if x flipped then
          inc(TmpData, LineSize - PixelSize);             //set last pixel
      end;
    end;

    /////////////////////////////////////////////////////////////////
    var
      Cache: PByte;
      CacheSize, CachePos: Integer;
    procedure CachedRead(out Buffer; Count: Integer);
    var
      BytesRead: Integer;
    begin
      if (CachePos + Count > CacheSize) then begin
        //if buffer overflow save non read bytes
        BytesRead := 0;
        if (CacheSize - CachePos > 0) then begin
          BytesRead := CacheSize - CachePos;
          Move(PByteArray(Cache)^[CachePos], Buffer{%H-}, BytesRead);
          inc(CachePos, BytesRead);
        end;

        //load cache from file
        CacheSize := Min(CACHE_SIZE, aStream.Size - aStream.Position);
        aStream.Read(Cache^, CacheSize);
        CachePos := 0;

        //read rest of requested bytes
        if (Count - BytesRead > 0) then begin
          Move(PByteArray(Cache)^[CachePos], TByteArray(Buffer)[BytesRead], Count - BytesRead);
          inc(CachePos, Count - BytesRead);
        end;
      end else begin
        //if no buffer overflow just read the data
        Move(PByteArray(Cache)^[CachePos], Buffer, Count);
        inc(CachePos, Count);
      end;
    end;

    procedure PixelToBuffer(const aData: PByte; var aBuffer: PByte);
    begin
      case PixelSize of
        1: begin
          aBuffer^ := aData^;
          inc(aBuffer, Counter.X.dir);
        end;
        2: begin
          PWord(aBuffer)^ := PWord(aData)^;
          inc(aBuffer, 2 * Counter.X.dir);
        end;
        3: begin
          PByteArray(aBuffer)^[0] := PByteArray(aData)^[0];
          PByteArray(aBuffer)^[1] := PByteArray(aData)^[1];
          PByteArray(aBuffer)^[2] := PByteArray(aData)^[2];
          inc(aBuffer, 3 * Counter.X.dir);
        end;
        4: begin
          PCardinal(aBuffer)^ := PCardinal(aData)^;
          inc(aBuffer, 4 * Counter.X.dir);
        end;
      end;
    end;

  var
    TotalPixelsToRead, TotalPixelsRead: Integer;
    Temp: Byte;
    buf: array [0..3] of Byte; //1 pixel is max 32bit long
    PixelRepeat: Boolean;
    PixelsToRead, PixelCount: Integer;
  begin
    CacheSize := 0;
    CachePos  := 0;

    TotalPixelsToRead := Header.Width * Header.Height;
    TotalPixelsRead   := 0;
    LinePixelsRead    := 0;

    GetMem(Cache, CACHE_SIZE);
    try
      TmpData := ImageData;
      inc(TmpData, Counter.Y.low * LineSize);           //set line
      if (Counter.X.dir < 0) then                       //if x flipped then
        inc(TmpData, LineSize - PixelSize);             //set last pixel

      repeat
        //read CommandByte
        CachedRead(Temp, 1);
        PixelRepeat  := (Temp and $80) > 0;
        PixelsToRead := (Temp and $7F) + 1;
        inc(TotalPixelsRead, PixelsToRead);

        if PixelRepeat then
          CachedRead(buf[0], PixelSize);
        while (PixelsToRead > 0) do begin
          CheckLine;
          PixelCount := Min(Header.Width - LinePixelsRead, PixelsToRead); //max read to EOL or EOF
          while (PixelCount > 0) do begin
            if not PixelRepeat then
              CachedRead(buf[0], PixelSize);
            PixelToBuffer(@buf[0], TmpData);
            inc(LinePixelsRead);
            dec(PixelsToRead);
            dec(PixelCount);
          end;
        end;
      until (TotalPixelsRead >= TotalPixelsToRead);
    finally
      FreeMem(Cache);
    end;
  end;

  function IsGrayFormat: Boolean;
  begin
    result := Header.ImageType in [TGA_UNCOMPRESSED_GRAY, TGA_COMPRESSED_GRAY];
  end;

begin
  result := false;

  // reading header to test file and set cursor back to begin
  StartPosition := aStream.Position;
  aStream.Read(Header{%H-}, SizeOf(Header));

  // no colormapped files
  if (Header.ColorMapType = TGA_NONE_COLOR_TABLE) and (Header.ImageType in [
    TGA_UNCOMPRESSED_RGB, TGA_UNCOMPRESSED_GRAY, TGA_COMPRESSED_RGB, TGA_COMPRESSED_GRAY]) then
  begin
    try
      if Header.ImageID <> 0 then       // skip image ID
        aStream.Position := aStream.Position + Header.ImageID;

      tgaFormat := tfEmpty;
      case Header.Bpp of
         8: if IsGrayFormat then case (Header.ImageDesc and $F) of
               0: tgaFormat := tfLuminance8;
               8: tgaFormat := tfAlpha8;
            end;

        16: if IsGrayFormat then case (Header.ImageDesc and $F) of
               0: tgaFormat := tfLuminance16;
               8: tgaFormat := tfLuminance8Alpha8;
            end else case (Header.ImageDesc and $F) of
               0: tgaFormat := tfBGR5;
               1: tgaFormat := tfBGR5A1;
               4: tgaFormat := tfBGRA4;
            end;

        24: if not IsGrayFormat then case (Header.ImageDesc and $F) of
               0: tgaFormat := tfBGR8;
            end;

        32: if not IsGrayFormat then case (Header.ImageDesc and $F) of
               2: tgaFormat := tfBGR10A2;
               8: tgaFormat := tfBGRA8;
            end;
      end;

      if (tgaFormat = tfEmpty) then
        raise EglBitmap.Create('LoadTga - unsupported format');

      FormatDesc := TFormatDescriptor.Get(tgaFormat);
      PixelSize  := FormatDesc.GetSize(1, 1);
      LineSize   := FormatDesc.GetSize(Header.Width, 1);

      GetMem(ImageData, LineSize * Header.Height);
      try
        //column direction
        if ((Header.ImageDesc and (1 shl 4)) > 0) then begin
          Counter.X.low  := Header.Height-1;;
          Counter.X.high := 0;
          Counter.X.dir  := -1;
        end else begin
          Counter.X.low  := 0;
          Counter.X.high := Header.Height-1;
          Counter.X.dir  := 1;
        end;

        // Row direction
        if ((Header.ImageDesc and (1 shl 5)) > 0) then begin
          Counter.Y.low  := 0;
          Counter.Y.high := Header.Height-1;
          Counter.Y.dir  := 1;
        end else begin
          Counter.Y.low  := Header.Height-1;;
          Counter.Y.high := 0;
          Counter.Y.dir  := -1;
        end;

        // Read Image
        case Header.ImageType of
          TGA_UNCOMPRESSED_RGB, TGA_UNCOMPRESSED_GRAY:
            ReadUncompressed;
          TGA_COMPRESSED_RGB, TGA_COMPRESSED_GRAY:
            ReadCompressed;
        end;

        SetDataPointer(ImageData, tgaFormat, Header.Width, Header.Height); //be careful, Data could be freed by this method
        result := true;
      except
        if Assigned(ImageData) then
          FreeMem(ImageData);
        raise;
      end;
    finally
      aStream.Position := StartPosition;
    end;
  end
    else aStream.Position := StartPosition;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveTGA(const aStream: TStream);
var
  Header: TTGAHeader;
  LineSize, Size, x, y: Integer;
  Pixel: TglBitmapPixelData;
  LineBuf, SourceData, DestData: PByte;
  SourceMD, DestMD: Pointer;
  FormatDesc: TFormatDescriptor;
  Converter: TFormatDescriptor;
begin
  if not (ftTGA in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  //prepare header
  FillChar(Header{%H-}, SizeOf(Header), 0);

  //set ImageType
  if (Format in [tfLuminance8, tfLuminance6Alpha2, tfLuminance4Alpha4, tfAlpha8,
                 tfLuminance16, tfLuminance12Alpha4, tfLuminance8Alpha8]) then
    Header.ImageType := TGA_UNCOMPRESSED_GRAY
  else
    Header.ImageType := TGA_UNCOMPRESSED_RGB;

  //set BitsPerPixel
  if (Format in [tfLuminance8, tfLuminance6Alpha2, tfLuminance4Alpha4, tfAlpha8]) then
    Header.Bpp := 8
  else if (Format in [tfLuminance16, tfLuminance12Alpha4, tfLuminance8Alpha8,
                      tfRGB5, tfBGR5, tfRGB5A1, tfBGR5A1, tfRGBA4, tfBGRA4]) then
    Header.Bpp := 16
  else if (Format in [tfBGR8, tfRGB8]) then
    Header.Bpp := 24
  else
    Header.Bpp := 32;

  //set AlphaBitCount
  case Format of
    tfRGB5A1, tfBGR5A1:
      Header.ImageDesc := 1 and $F;
    tfRGB10A2, tfBGR10A2:
      Header.ImageDesc := 2 and $F;
    tfRGBA4, tfBGRA4:
      Header.ImageDesc := 4 and $F;
    tfAlpha8, tfLuminance8Alpha8, tfRGBA8, tfBGRA8:
      Header.ImageDesc := 8 and $F;
  end;

  Header.Width     := Width;
  Header.Height    := Height;
  Header.ImageDesc := Header.ImageDesc or $20; //flip y
  aStream.Write(Header, SizeOf(Header));

  // convert RGB(A) to BGR(A)
  Converter  := nil;
  FormatDesc := TFormatDescriptor.Get(Format);
  Size       := FormatDesc.GetSize(Dimension);
  if Format in [tfRGB5, tfRGB5A1, tfRGBA4, tfRGB8, tfRGB10A2, tfRGBA8] then begin
    if (FormatDesc.RGBInverted = tfEmpty) then
      raise EglBitmap.Create('inverted RGB format is empty');
    Converter := TFormatDescriptor.Get(FormatDesc.RGBInverted);
    if not glBitmapColorRecCmp(Converter.Range, FormatDesc.Range) or
       (Converter.PixelSize <> FormatDesc.PixelSize) then
      raise EglBitmap.Create('invalid inverted RGB format');
  end;

  if Assigned(Converter) then begin
    LineSize := FormatDesc.GetSize(Width, 1);
    GetMem(LineBuf, LineSize);
    SourceMD := FormatDesc.CreateMappingData;
    DestMD   := Converter.CreateMappingData;
    try
      SourceData := Data;
      for y := 0 to Height-1 do begin
        DestData := LineBuf;
        for x := 0 to Width-1 do begin
          FormatDesc.Unmap(SourceData, Pixel, SourceMD);
          Converter.Map(Pixel, DestData, DestMD);
        end;
        aStream.Write(LineBuf^, LineSize);
      end;
    finally
      FreeMem(LineBuf);
      FormatDesc.FreeMappingData(SourceMD);
      FormatDesc.FreeMappingData(DestMD);
    end;
  end else
    aStream.Write(Data^, Size);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//DDS/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
const
  DDS_MAGIC: Cardinal         = $20534444;

  // DDS_header.dwFlags
  DDSD_CAPS                   = $00000001;
  DDSD_HEIGHT                 = $00000002;
  DDSD_WIDTH                  = $00000004;
  DDSD_PIXELFORMAT            = $00001000;

  // DDS_header.sPixelFormat.dwFlags
  DDPF_ALPHAPIXELS            = $00000001;
  DDPF_ALPHA                  = $00000002;
  DDPF_FOURCC                 = $00000004;
  DDPF_RGB                    = $00000040;
  DDPF_LUMINANCE              = $00020000;

  // DDS_header.sCaps.dwCaps1
  DDSCAPS_TEXTURE             = $00001000;

  // DDS_header.sCaps.dwCaps2
  DDSCAPS2_CUBEMAP            = $00000200;

  D3DFMT_DXT1                 = $31545844;
  D3DFMT_DXT3                 = $33545844;
  D3DFMT_DXT5                 = $35545844;

type
  TDDSPixelFormat = packed record
    dwSize: Cardinal;
    dwFlags: Cardinal;
    dwFourCC: Cardinal;
    dwRGBBitCount: Cardinal;
    dwRBitMask: Cardinal;
    dwGBitMask: Cardinal;
    dwBBitMask: Cardinal;
    dwABitMask: Cardinal;
  end;

  TDDSCaps = packed record
    dwCaps1: Cardinal;
    dwCaps2: Cardinal;
    dwDDSX: Cardinal;
    dwReserved: Cardinal;
  end;

  TDDSHeader = packed record
    dwSize: Cardinal;
    dwFlags: Cardinal;
    dwHeight: Cardinal;
    dwWidth: Cardinal;
    dwPitchOrLinearSize: Cardinal;
    dwDepth: Cardinal;
    dwMipMapCount: Cardinal;
    dwReserved: array[0..10] of Cardinal;
    PixelFormat: TDDSPixelFormat;
    Caps: TDDSCaps;
    dwReserved2: Cardinal;
  end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap.LoadDDS(const aStream: TStream): Boolean;
var
  Header: TDDSHeader;
  Converter: TbmpBitfieldFormat;

  function GetDDSFormat: TglBitmapFormat;
  var
    fd: TFormatDescriptor;
    i: Integer;
    Range: TglBitmapColorRec;
    match: Boolean;
  begin
    result := tfEmpty;
    with Header.PixelFormat do begin
      // Compresses
      if ((dwFlags and DDPF_FOURCC) > 0) then begin
        case Header.PixelFormat.dwFourCC of
          D3DFMT_DXT1: result := tfS3tcDtx1RGBA;
          D3DFMT_DXT3: result := tfS3tcDtx3RGBA;
          D3DFMT_DXT5: result := tfS3tcDtx5RGBA;
        end;
      end else if ((Header.PixelFormat.dwFlags and (DDPF_RGB or DDPF_ALPHAPIXELS or DDPF_LUMINANCE)) > 0) then begin

        //find matching format
        for result := High(TglBitmapFormat) downto Low(TglBitmapFormat) do begin
          fd := TFormatDescriptor.Get(result);
          if fd.MaskMatch(dwRBitMask, dwGBitMask, dwBBitMask, dwABitMask) and
             (8 * fd.PixelSize = dwRGBBitCount) then
            exit;
        end;

        //find format with same Range
        Range.r := dwRBitMask;
        Range.g := dwGBitMask;
        Range.b := dwBBitMask;
        Range.a := dwABitMask;
        for i := 0 to 3 do begin
          while ((Range.arr[i] and 1) = 0) and (Range.arr[i] > 0) do
            Range.arr[i] := Range.arr[i] shr 1;
        end;
        for result := High(TglBitmapFormat) downto Low(TglBitmapFormat) do begin
          fd := TFormatDescriptor.Get(result);
          match := true;
          for i := 0 to 3 do
            if (fd.Range.arr[i] <> Range.arr[i]) then begin
              match := false;
              break;
            end;
          if match then
            break;
        end;

        //no format with same range found -> use default
        if (result = tfEmpty) then begin
          if (dwABitMask > 0) then
            result := tfBGRA8
          else
            result := tfBGR8;
        end;

        Converter := TbmpBitfieldFormat.Create;
        Converter.RedMask   := dwRBitMask;
        Converter.GreenMask := dwGBitMask;
        Converter.BlueMask  := dwBBitMask;
        Converter.AlphaMask := dwABitMask;
        Converter.PixelSize := dwRGBBitCount / 8;
      end;
    end;
  end;

var
  StreamPos: Int64;
  x, y, LineSize, RowSize, Magic: Cardinal;
  NewImage, TmpData, RowData, SrcData: System.PByte;
  SourceMD, DestMD: Pointer;
  Pixel: TglBitmapPixelData;
  ddsFormat: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;

begin
  result    := false;
  Converter := nil;
  StreamPos := aStream.Position;

  // Magic
  aStream.Read(Magic{%H-}, sizeof(Magic));
  if (Magic <> DDS_MAGIC) then begin
    aStream.Position := StreamPos;
    exit;
  end;

  //Header
  aStream.Read(Header{%H-}, sizeof(Header));
  if (Header.dwSize <> SizeOf(Header)) or
     ((Header.dwFlags and (DDSD_PIXELFORMAT or DDSD_CAPS or DDSD_WIDTH or DDSD_HEIGHT)) <>
        (DDSD_PIXELFORMAT or DDSD_CAPS or DDSD_WIDTH or DDSD_HEIGHT)) then
  begin
    aStream.Position := StreamPos;
    exit;
  end;

  if ((Header.Caps.dwCaps1 and DDSCAPS2_CUBEMAP) > 0) then
    raise EglBitmap.Create('LoadDDS - CubeMaps are not supported');

  ddsFormat := GetDDSFormat;
  try
    if (ddsFormat = tfEmpty) then
      raise EglBitmap.Create('LoadDDS - unsupported Pixelformat found.');

    FormatDesc := TFormatDescriptor.Get(ddsFormat);
    LineSize   := Trunc(Header.dwWidth * FormatDesc.PixelSize);
    GetMem(NewImage, Header.dwHeight * LineSize);
    try
      TmpData := NewImage;

      //Converter needed
      if Assigned(Converter) then begin
        RowSize := Round(Header.dwWidth * Header.PixelFormat.dwRGBBitCount / 8);
        GetMem(RowData, RowSize);
        SourceMD := Converter.CreateMappingData;
        DestMD   := FormatDesc.CreateMappingData;
        try
          for y := 0 to Header.dwHeight-1 do begin
            TmpData := NewImage;
            inc(TmpData, y * LineSize);
            SrcData := RowData;
            aStream.Read(SrcData^, RowSize);
            for x := 0 to Header.dwWidth-1 do begin
              Converter.Unmap(SrcData, Pixel, SourceMD);
              glBitmapConvertPixel(Pixel, Converter, FormatDesc);
              FormatDesc.Map(Pixel, TmpData, DestMD);
            end;
          end;
        finally
          Converter.FreeMappingData(SourceMD);
          FormatDesc.FreeMappingData(DestMD);
          FreeMem(RowData);
        end;
      end else

      // Compressed
      if ((Header.PixelFormat.dwFlags and DDPF_FOURCC) > 0) then begin
        RowSize := Header.dwPitchOrLinearSize div Header.dwWidth;
        for Y := 0 to Header.dwHeight-1 do begin
          aStream.Read(TmpData^, RowSize);
          Inc(TmpData, LineSize);
        end;
      end else

      // Uncompressed
      if (Header.PixelFormat.dwFlags and (DDPF_RGB or DDPF_ALPHAPIXELS or DDPF_LUMINANCE)) > 0 then begin
        RowSize := (Header.PixelFormat.dwRGBBitCount * Header.dwWidth) shr 3;
        for Y := 0 to Header.dwHeight-1 do begin
          aStream.Read(TmpData^, RowSize);
          Inc(TmpData, LineSize);
        end;
      end else
        raise EglBitmap.Create('LoadDDS - unsupported Pixelformat found.');

      SetDataPointer(NewImage, ddsFormat, Header.dwWidth, Header.dwHeight); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(NewImage) then
        FreeMem(NewImage);
      raise;
    end;
  finally
    FreeAndNil(Converter);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap.SaveDDS(const aStream: TStream);
var
  Header: TDDSHeader;
  FormatDesc: TFormatDescriptor;
begin
  if not (ftDDS in FormatGetSupportedFiles(Format)) then
    raise EglBitmapUnsupportedFormat.Create(Format);

  FormatDesc := TFormatDescriptor.Get(Format);

  // Generell
  FillChar(Header{%H-}, SizeOf(Header), 0);
  Header.dwSize  := SizeOf(Header);
  Header.dwFlags := DDSD_WIDTH or DDSD_HEIGHT or DDSD_CAPS or DDSD_PIXELFORMAT;

  Header.dwWidth  := Max(1, Width);
  Header.dwHeight := Max(1, Height);

  // Caps
  Header.Caps.dwCaps1 := DDSCAPS_TEXTURE;

  // Pixelformat
  Header.PixelFormat.dwSize := sizeof(Header);
  if (FormatDesc.IsCompressed) then begin
    Header.PixelFormat.dwFlags := Header.PixelFormat.dwFlags or DDPF_FOURCC;
    case Format of
      tfS3tcDtx1RGBA: Header.PixelFormat.dwFourCC := D3DFMT_DXT1;
      tfS3tcDtx3RGBA: Header.PixelFormat.dwFourCC := D3DFMT_DXT3;
      tfS3tcDtx5RGBA: Header.PixelFormat.dwFourCC := D3DFMT_DXT5;
    end;
  end else if (Format in [tfAlpha8, tfAlpha16]) then begin
    Header.PixelFormat.dwFlags       := Header.PixelFormat.dwFlags or DDPF_ALPHA;
    Header.PixelFormat.dwRGBBitCount := Round(FormatDesc.PixelSize * 8);
    Header.PixelFormat.dwABitMask    := FormatDesc.AlphaMask;
  end else if (FormatDesc.RedMask = FormatDesc.GreenMask) and (FormatDesc.GreenMask = FormatDesc.BlueMask) then begin
    Header.PixelFormat.dwFlags       := Header.PixelFormat.dwFlags or DDPF_LUMINANCE;
    Header.PixelFormat.dwRGBBitCount := Round(FormatDesc.PixelSize * 8);
    Header.PixelFormat.dwRBitMask    := FormatDesc.RedMask;
    Header.PixelFormat.dwABitMask    := FormatDesc.AlphaMask;
  end else begin
    Header.PixelFormat.dwFlags := Header.PixelFormat.dwFlags or DDPF_RGB;
    Header.PixelFormat.dwRGBBitCount := Round(FormatDesc.PixelSize * 8);
    Header.PixelFormat.dwRBitMask    := FormatDesc.RedMask;
    Header.PixelFormat.dwGBitMask    := FormatDesc.GreenMask;
    Header.PixelFormat.dwBBitMask    := FormatDesc.BlueMask;
    Header.PixelFormat.dwABitMask    := FormatDesc.AlphaMask;
  end;

  if (FormatDesc.HasAlpha) then
    Header.PixelFormat.dwFlags := Header.PixelFormat.dwFlags or DDPF_ALPHAPIXELS;

  aStream.Write(DDS_MAGIC, sizeof(DDS_MAGIC));
  aStream.Write(Header, SizeOf(Header));
  aStream.Write(Data^, FormatDesc.GetSize(Dimension));
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap1D/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap1D.SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
  const aWidth: Integer; const aHeight: Integer);
var
  pTemp: pByte;
  Size: Integer;
begin
  if (aHeight > 1) then begin
    Size := TFormatDescriptor.Get(aFormat).GetSize(aWidth, 1);
    GetMem(pTemp, Size);
    try
      Move(aData^, pTemp^, Size);
      FreeMem(aData);
      aData := nil;
    except
      FreeMem(pTemp);
      raise;
    end;
  end else
    pTemp := aData;
  inherited SetDataPointer(pTemp, aFormat, aWidth);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap1D.FlipHorz: Boolean;
var
  Col: Integer;
  pTempDest, pDest, pSource: PByte;
begin
  result := inherited FlipHorz;
  if Assigned(Data) and not TFormatDescriptor.Get(Format).IsCompressed then begin
    pSource := Data;
    GetMem(pDest, fRowSize);
    try
      pTempDest := pDest;
      Inc(pTempDest, fRowSize);
      for Col := 0 to Width-1 do begin
        dec(pTempDest, fPixelSize); //dec before, because ptr is behind last byte of data
        Move(pSource^, pTempDest^, fPixelSize);
        Inc(pSource, fPixelSize);
      end;
      SetDataPointer(pDest, Format, Width); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(pDest) then
        FreeMem(pDest);
      raise;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap1D.UploadData(const aBuildWithGlu: Boolean);
var
  FormatDesc: TFormatDescriptor;
begin
  // Upload data
  FormatDesc := TFormatDescriptor.Get(Format);
  if FormatDesc.IsCompressed then begin
    if not Assigned(glCompressedTexImage1D) then
      raise EglBitmap.Create('compressed formats not supported by video adapter');
    glCompressedTexImage1D(Target, 0, FormatDesc.glInternalFormat, Width, 0, FormatDesc.GetSize(Width, 1), Data)
  end else if aBuildWithGlu then
    gluBuild1DMipmaps(Target, FormatDesc.glInternalFormat, Width, FormatDesc.glFormat, FormatDesc.glDataFormat, Data)
  else
    glTexImage1D(Target, 0, FormatDesc.glInternalFormat, Width, 0, FormatDesc.glFormat, FormatDesc.glDataFormat, Data);

  // Free Data
  if (FreeDataAfterGenTexture) then
    FreeData;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap1D.GenTexture(const aTestTextureSize: Boolean);
var
  BuildWithGlu, TexRec: Boolean;
  TexSize: Integer;
begin
  if Assigned(Data) then begin
    // Check Texture Size
    if (aTestTextureSize) then begin
      glGetIntegerv(GL_MAX_TEXTURE_SIZE, @TexSize);

      if (Width > TexSize) then
        raise EglBitmapSizeToLarge.Create('TglBitmap1D.GenTexture - The size for the texture is to large. It''s may be not conform with the Hardware.');

      TexRec := (GL_ARB_texture_rectangle or GL_EXT_texture_rectangle or GL_NV_texture_rectangle) and
                (Target = GL_TEXTURE_RECTANGLE);
      if not (IsPowerOfTwo(Width) or GL_ARB_texture_non_power_of_two or GL_VERSION_2_0 or TexRec) then
        raise EglBitmapNonPowerOfTwo.Create('TglBitmap1D.GenTexture - Rendercontex dosn''t support non power of two texture.');
    end;

    CreateId;
    SetupParameters(BuildWithGlu);
    UploadData(BuildWithGlu);
    glAreTexturesResident(1, @fID, @fIsResident);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap1D.AfterConstruction;
begin
  inherited;
  Target := GL_TEXTURE_1D;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap2D/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap2D.GetScanline(const aIndex: Integer): Pointer;
begin
  if (aIndex >= Low(fLines)) and (aIndex <= High(fLines)) then
    result := fLines[aIndex]
  else
    result := nil;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.SetDataPointer(var aData: PByte; const aFormat: TglBitmapFormat;
  const aWidth: Integer; const aHeight: Integer);
var
  Idx, LineWidth: Integer;
begin
  inherited SetDataPointer(aData, aFormat, aWidth, aHeight);

  if not TFormatDescriptor.Get(aFormat).IsCompressed then begin
    // Assigning Data
    if Assigned(Data) then begin
      SetLength(fLines, GetHeight);
      LineWidth := Trunc(GetWidth * TFormatDescriptor.Get(Format).PixelSize);

      for Idx := 0 to GetHeight-1 do begin
        fLines[Idx] := Data;
        Inc(fLines[Idx], Idx * LineWidth);
      end;
    end
      else SetLength(fLines, 0);
  end else begin
    SetLength(fLines, 0);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.UploadData(const aTarget: GLenum; const aBuildWithGlu: Boolean);
var
  FormatDesc: TFormatDescriptor;
begin
  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

  FormatDesc := TFormatDescriptor.Get(Format);
  if FormatDesc.IsCompressed then begin
    if not Assigned(glCompressedTexImage2D) then
      raise EglBitmap.Create('compressed formats not supported by video adapter');
    glCompressedTexImage2D(aTarget, 0, FormatDesc.glInternalFormat, Width, Height, 0, FormatDesc.GetSize(fDimension), Data)
  end else if aBuildWithGlu then begin
    gluBuild2DMipmaps(aTarget, FormatDesc.Components, Width, Height,
      FormatDesc.glFormat, FormatDesc.glDataFormat, Data)
  end else begin
    glTexImage2D(aTarget, 0, FormatDesc.glInternalFormat, Width, Height, 0,
      FormatDesc.glFormat, FormatDesc.glDataFormat, Data);
  end;

  // Freigeben
  if (FreeDataAfterGenTexture) then
    FreeData;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.AfterConstruction;
begin
  inherited;
  Target := GL_TEXTURE_2D;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.GrabScreen(const aTop, aLeft, aRight, aBottom: Integer; const aFormat: TglBitmapFormat);
var
  Temp: pByte;
  Size, w, h: Integer;
  FormatDesc: TFormatDescriptor;
begin
  FormatDesc := TFormatDescriptor.Get(aFormat);
  if FormatDesc.IsCompressed then
    raise EglBitmapUnsupportedFormat.Create(aFormat);

  w    := aRight  - aLeft;
  h    := aBottom - aTop;
  Size := FormatDesc.GetSize(w, h);
  GetMem(Temp, Size);
  try
    glPixelStorei(GL_PACK_ALIGNMENT, 1);
    glReadPixels(aLeft, aTop, w, h, FormatDesc.glFormat, FormatDesc.glDataFormat, Temp);
    SetDataPointer(Temp, aFormat, w, h); //be careful, Data could be freed by this method
    FlipVert;
  except
    if Assigned(Temp) then
      FreeMem(Temp);
    raise;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.GetDataFromTexture;
var
  Temp: PByte;
  TempWidth, TempHeight: Integer;
  TempIntFormat: Cardinal;
  IntFormat, f: TglBitmapFormat;
  FormatDesc: TFormatDescriptor;
begin
  Bind;

  // Request Data
  glGetTexLevelParameteriv(Target, 0, GL_TEXTURE_WIDTH,           @TempWidth);
  glGetTexLevelParameteriv(Target, 0, GL_TEXTURE_HEIGHT,          @TempHeight);
  glGetTexLevelParameteriv(Target, 0, GL_TEXTURE_INTERNAL_FORMAT, @TempIntFormat);

  IntFormat := tfEmpty;
  for f := Low(TglBitmapFormat) to High(TglBitmapFormat) do begin
    FormatDesc := TFormatDescriptor.Get(f);
    if (FormatDesc.glInternalFormat = TempIntFormat) then begin
      IntFormat := FormatDesc.Format;
      break;
    end;
  end;

  // Getting data from OpenGL
  FormatDesc := TFormatDescriptor.Get(IntFormat);
  GetMem(Temp, FormatDesc.GetSize(TempWidth, TempHeight));
  try
    if FormatDesc.IsCompressed then begin
      if not Assigned(glGetCompressedTexImage) then
        raise EglBitmap.Create('compressed formats not supported by video adapter');
      glGetCompressedTexImage(Target, 0, Temp)
    end else
      glGetTexImage(Target, 0, FormatDesc.glFormat, FormatDesc.glDataFormat, Temp);
    SetDataPointer(Temp, IntFormat, TempWidth, TempHeight); //be careful, Data could be freed by this method
  except
    if Assigned(Temp) then
      FreeMem(Temp);
    raise;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.GenTexture(const aTestTextureSize: Boolean);
var
  BuildWithGlu, PotTex, TexRec: Boolean;
  TexSize: Integer;
begin
  if Assigned(Data) then begin
    // Check Texture Size
    if (aTestTextureSize) then begin
      glGetIntegerv(GL_MAX_TEXTURE_SIZE, @TexSize);

      if ((Height > TexSize) or (Width > TexSize)) then
        raise EglBitmapSizeToLarge.Create('TglBitmap2D.GenTexture - The size for the texture is to large. It''s may be not conform with the Hardware.');

      PotTex := IsPowerOfTwo(Height) and IsPowerOfTwo(Width);
      TexRec := (GL_ARB_texture_rectangle or GL_EXT_texture_rectangle or GL_NV_texture_rectangle) and (Target = GL_TEXTURE_RECTANGLE);
      if not (PotTex or GL_ARB_texture_non_power_of_two or GL_VERSION_2_0 or TexRec) then
        raise EglBitmapNonPowerOfTwo.Create('TglBitmap2D.GenTexture - Rendercontex dosn''t support non power of two texture.');
    end;

    CreateId;
    SetupParameters(BuildWithGlu);
    UploadData(Target, BuildWithGlu);
    glAreTexturesResident(1, @fID, @fIsResident);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap2D.FlipHorz: Boolean;
var
  Col, Row: Integer;
  TempDestData, DestData, SourceData: PByte;
  ImgSize: Integer;
begin
  result := inherited FlipHorz;
  if Assigned(Data) then begin
    SourceData := Data;
    ImgSize := Height * fRowSize;
    GetMem(DestData, ImgSize);
    try
      TempDestData := DestData;
      Dec(TempDestData, fRowSize + fPixelSize);
      for Row := 0 to Height -1 do begin
        Inc(TempDestData, fRowSize * 2);
        for Col := 0 to Width -1 do begin
          Move(SourceData^, TempDestData^, fPixelSize);
          Inc(SourceData, fPixelSize);
          Dec(TempDestData, fPixelSize);
        end;
      end;
      SetDataPointer(DestData, Format); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(DestData) then
        FreeMem(DestData);
      raise;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TglBitmap2D.FlipVert: Boolean;
var
  Row: Integer;
  TempDestData, DestData, SourceData: PByte;
begin
  result := inherited FlipVert;
  if Assigned(Data) then begin
    SourceData := Data;
    GetMem(DestData, Height * fRowSize);
    try
      TempDestData := DestData;
      Inc(TempDestData, Width * (Height -1) * fPixelSize);
      for Row := 0 to Height -1 do begin
        Move(SourceData^, TempDestData^, fRowSize);
        Dec(TempDestData, fRowSize);
        Inc(SourceData, fRowSize);
      end;
      SetDataPointer(DestData, Format); //be careful, Data could be freed by this method
      result := true;
    except
      if Assigned(DestData) then
        FreeMem(DestData);
      raise;
    end;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmap2D - ToNormalMap///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
type
  TMatrixItem = record
    X, Y: Integer;
    W: Single;
  end;

  PglBitmapToNormalMapRec = ^TglBitmapToNormalMapRec;
  TglBitmapToNormalMapRec = Record
    Scale: Single;
    Heights: array of Single;
    MatrixU : array of TMatrixItem;
    MatrixV : array of TMatrixItem;
  end;

const
  ONE_OVER_255 = 1 / 255;

  //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapToNormalMapPrepareFunc(var FuncRec: TglBitmapFunctionRec);
var
  Val: Single;
begin
  with FuncRec do begin
    Val :=
      Source.Data.r * LUMINANCE_WEIGHT_R +
      Source.Data.g * LUMINANCE_WEIGHT_G +
      Source.Data.b * LUMINANCE_WEIGHT_B;
    PglBitmapToNormalMapRec(Args)^.Heights[Position.Y * Size.X + Position.X] := Val * ONE_OVER_255;
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapToNormalMapPrepareAlphaFunc(var FuncRec: TglBitmapFunctionRec);
begin
  with FuncRec do
    PglBitmapToNormalMapRec(Args)^.Heights[Position.Y * Size.X + Position.X] := Source.Data.a * ONE_OVER_255;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapToNormalMapFunc (var FuncRec: TglBitmapFunctionRec);
type
  TVec = Array[0..2] of Single;
var
  Idx: Integer;
  du, dv: Double;
  Len: Single;
  Vec: TVec;

  function GetHeight(X, Y: Integer): Single;
  begin
    with FuncRec do begin
      X := Max(0, Min(Size.X -1, X));
      Y := Max(0, Min(Size.Y -1, Y));
      result := PglBitmapToNormalMapRec(Args)^.Heights[Y * Size.X + X];
    end;
  end;

begin
  with FuncRec do begin
    with PglBitmapToNormalMapRec(Args)^ do begin
      du := 0;
      for Idx := Low(MatrixU) to High(MatrixU) do
        du := du + GetHeight(Position.X + MatrixU[Idx].X, Position.Y + MatrixU[Idx].Y) * MatrixU[Idx].W;

      dv := 0;
      for Idx := Low(MatrixU) to High(MatrixU) do
        dv := dv + GetHeight(Position.X + MatrixV[Idx].X, Position.Y + MatrixV[Idx].Y) * MatrixV[Idx].W;

      Vec[0] := -du * Scale;
      Vec[1] := -dv * Scale;
      Vec[2] := 1;
    end;

    // Normalize
    Len := 1 / Sqrt(Sqr(Vec[0]) + Sqr(Vec[1]) + Sqr(Vec[2]));
    if Len <> 0 then begin
      Vec[0] := Vec[0] * Len;
      Vec[1] := Vec[1] * Len;
      Vec[2] := Vec[2] * Len;
    end;

    // Farbe zuweisem
    Dest.Data.r := Trunc((Vec[0] + 1) * 127.5);
    Dest.Data.g := Trunc((Vec[1] + 1) * 127.5);
    Dest.Data.b := Trunc((Vec[2] + 1) * 127.5);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmap2D.ToNormalMap(const aFunc: TglBitmapNormalMapFunc; const aScale: Single; const aUseAlpha: Boolean);
var
  Rec: TglBitmapToNormalMapRec;

  procedure SetEntry (var Matrix: array of TMatrixItem; Index, X, Y: Integer; W: Single);
  begin
    if (Index >= Low(Matrix)) and (Index <= High(Matrix)) then begin
      Matrix[Index].X := X;
      Matrix[Index].Y := Y;
      Matrix[Index].W := W;
    end;
  end;

begin
  if TFormatDescriptor.Get(Format).IsCompressed then
    raise EglBitmapUnsupportedFormat.Create(Format);

  if aScale > 100 then
    Rec.Scale := 100
  else if aScale < -100 then
    Rec.Scale := -100
  else
    Rec.Scale := aScale;

  SetLength(Rec.Heights, Width * Height);
  try
    case aFunc of
      nm4Samples: begin
        SetLength(Rec.MatrixU, 2);
        SetEntry(Rec.MatrixU, 0, -1,  0, -0.5);
        SetEntry(Rec.MatrixU, 1,  1,  0,  0.5);

        SetLength(Rec.MatrixV, 2);
        SetEntry(Rec.MatrixV, 0,  0,  1,  0.5);
        SetEntry(Rec.MatrixV, 1,  0, -1, -0.5);
      end;

      nmSobel: begin
        SetLength(Rec.MatrixU, 6);
        SetEntry(Rec.MatrixU, 0, -1,  1, -1.0);
        SetEntry(Rec.MatrixU, 1, -1,  0, -2.0);
        SetEntry(Rec.MatrixU, 2, -1, -1, -1.0);
        SetEntry(Rec.MatrixU, 3,  1,  1,  1.0);
        SetEntry(Rec.MatrixU, 4,  1,  0,  2.0);
        SetEntry(Rec.MatrixU, 5,  1, -1,  1.0);

        SetLength(Rec.MatrixV, 6);
        SetEntry(Rec.MatrixV, 0, -1,  1,  1.0);
        SetEntry(Rec.MatrixV, 1,  0,  1,  2.0);
        SetEntry(Rec.MatrixV, 2,  1,  1,  1.0);
        SetEntry(Rec.MatrixV, 3, -1, -1, -1.0);
        SetEntry(Rec.MatrixV, 4,  0, -1, -2.0);
        SetEntry(Rec.MatrixV, 5,  1, -1, -1.0);
      end;

      nm3x3: begin
        SetLength(Rec.MatrixU, 6);
        SetEntry(Rec.MatrixU, 0, -1,  1, -1/6);
        SetEntry(Rec.MatrixU, 1, -1,  0, -1/6);
        SetEntry(Rec.MatrixU, 2, -1, -1, -1/6);
        SetEntry(Rec.MatrixU, 3,  1,  1,  1/6);
        SetEntry(Rec.MatrixU, 4,  1,  0,  1/6);
        SetEntry(Rec.MatrixU, 5,  1, -1,  1/6);

        SetLength(Rec.MatrixV, 6);
        SetEntry(Rec.MatrixV, 0, -1,  1,  1/6);
        SetEntry(Rec.MatrixV, 1,  0,  1,  1/6);
        SetEntry(Rec.MatrixV, 2,  1,  1,  1/6);
        SetEntry(Rec.MatrixV, 3, -1, -1, -1/6);
        SetEntry(Rec.MatrixV, 4,  0, -1, -1/6);
        SetEntry(Rec.MatrixV, 5,  1, -1, -1/6);
      end;

      nm5x5: begin
        SetLength(Rec.MatrixU, 20);
        SetEntry(Rec.MatrixU,  0, -2,  2, -1 / 16);
        SetEntry(Rec.MatrixU,  1, -1,  2, -1 / 10);
        SetEntry(Rec.MatrixU,  2,  1,  2,  1 / 10);
        SetEntry(Rec.MatrixU,  3,  2,  2,  1 / 16);
        SetEntry(Rec.MatrixU,  4, -2,  1, -1 / 10);
        SetEntry(Rec.MatrixU,  5, -1,  1, -1 /  8);
        SetEntry(Rec.MatrixU,  6,  1,  1,  1 /  8);
        SetEntry(Rec.MatrixU,  7,  2,  1,  1 / 10);
        SetEntry(Rec.MatrixU,  8, -2,  0, -1 / 2.8);
        SetEntry(Rec.MatrixU,  9, -1,  0, -0.5);
        SetEntry(Rec.MatrixU, 10,  1,  0,  0.5);
        SetEntry(Rec.MatrixU, 11,  2,  0,  1 / 2.8);
        SetEntry(Rec.MatrixU, 12, -2, -1, -1 / 10);
        SetEntry(Rec.MatrixU, 13, -1, -1, -1 /  8);
        SetEntry(Rec.MatrixU, 14,  1, -1,  1 /  8);
        SetEntry(Rec.MatrixU, 15,  2, -1,  1 / 10);
        SetEntry(Rec.MatrixU, 16, -2, -2, -1 / 16);
        SetEntry(Rec.MatrixU, 17, -1, -2, -1 / 10);
        SetEntry(Rec.MatrixU, 18,  1, -2,  1 / 10);
        SetEntry(Rec.MatrixU, 19,  2, -2,  1 / 16);

        SetLength(Rec.MatrixV, 20);
        SetEntry(Rec.MatrixV,  0, -2,  2,  1 / 16);
        SetEntry(Rec.MatrixV,  1, -1,  2,  1 / 10);
        SetEntry(Rec.MatrixV,  2,  0,  2,  0.25);
        SetEntry(Rec.MatrixV,  3,  1,  2,  1 / 10);
        SetEntry(Rec.MatrixV,  4,  2,  2,  1 / 16);
        SetEntry(Rec.MatrixV,  5, -2,  1,  1 / 10);
        SetEntry(Rec.MatrixV,  6, -1,  1,  1 /  8);
        SetEntry(Rec.MatrixV,  7,  0,  1,  0.5);
        SetEntry(Rec.MatrixV,  8,  1,  1,  1 /  8);
        SetEntry(Rec.MatrixV,  9,  2,  1,  1 / 16);
        SetEntry(Rec.MatrixV, 10, -2, -1, -1 / 16);
        SetEntry(Rec.MatrixV, 11, -1, -1, -1 /  8);
        SetEntry(Rec.MatrixV, 12,  0, -1, -0.5);
        SetEntry(Rec.MatrixV, 13,  1, -1, -1 /  8);
        SetEntry(Rec.MatrixV, 14,  2, -1, -1 / 10);
        SetEntry(Rec.MatrixV, 15, -2, -2, -1 / 16);
        SetEntry(Rec.MatrixV, 16, -1, -2, -1 / 10);
        SetEntry(Rec.MatrixV, 17,  0, -2, -0.25);
        SetEntry(Rec.MatrixV, 18,  1, -2, -1 / 10);
        SetEntry(Rec.MatrixV, 19,  2, -2, -1 / 16);
      end;
    end;

    // Daten Sammeln
    if aUseAlpha and TFormatDescriptor.Get(Format).HasAlpha then
      AddFunc(glBitmapToNormalMapPrepareAlphaFunc, false, @Rec)
    else
      AddFunc(glBitmapToNormalMapPrepareFunc, false, @Rec);
    AddFunc(glBitmapToNormalMapFunc, false, @Rec);
  finally
    SetLength(Rec.Heights, 0);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmapCubeMap////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapCubeMap.GenTexture(const aTestTextureSize: Boolean);
begin
  Assert(false, 'TglBitmapCubeMap.GenTexture - Don''t call GenTextures directly.');
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapCubeMap.AfterConstruction;
begin
  inherited;

  if not (GL_VERSION_1_3 or GL_ARB_texture_cube_map or GL_EXT_texture_cube_map) then
    raise EglBitmap.Create('TglBitmapCubeMap.AfterConstruction - CubeMaps are unsupported.');

  SetWrap;
  Target   := GL_TEXTURE_CUBE_MAP;
  fGenMode := GL_REFLECTION_MAP;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapCubeMap.GenerateCubeMap(const aCubeTarget: Cardinal; const aTestTextureSize: Boolean);
var
  BuildWithGlu: Boolean;
  TexSize: Integer;
begin
  if (aTestTextureSize) then begin
    glGetIntegerv(GL_MAX_CUBE_MAP_TEXTURE_SIZE, @TexSize);

    if (Height > TexSize) or (Width > TexSize) then
      raise EglBitmapSizeToLarge.Create('TglBitmapCubeMap.GenTexture - The size for the Cubemap is to large. It''s may be not conform with the Hardware.');

    if not ((IsPowerOfTwo(Height) and IsPowerOfTwo(Width)) or GL_VERSION_2_0 or GL_ARB_texture_non_power_of_two) then
      raise EglBitmapNonPowerOfTwo.Create('TglBitmapCubeMap.GenTexture - Cubemaps dosn''t support non power of two texture.');
  end;

  if (ID = 0) then
    CreateID;
  SetupParameters(BuildWithGlu);
  UploadData(aCubeTarget, BuildWithGlu);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapCubeMap.Bind(const aEnableTexCoordsGen: Boolean; const aEnableTextureUnit: Boolean);
begin
  inherited Bind (aEnableTextureUnit);
  if aEnableTexCoordsGen then begin
    glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, fGenMode);
    glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, fGenMode);
    glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, fGenMode);
    glEnable(GL_TEXTURE_GEN_S);
    glEnable(GL_TEXTURE_GEN_T);
    glEnable(GL_TEXTURE_GEN_R);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapCubeMap.Unbind(const aDisableTexCoordsGen: Boolean; const aDisableTextureUnit: Boolean);
begin
  inherited Unbind(aDisableTextureUnit);
  if aDisableTexCoordsGen then begin
    glDisable(GL_TEXTURE_GEN_S);
    glDisable(GL_TEXTURE_GEN_T);
    glDisable(GL_TEXTURE_GEN_R);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TglBitmapNormalMap//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
type
  TVec = Array[0..2] of Single;
  TglBitmapNormalMapGetVectorFunc = procedure (out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);

  PglBitmapNormalMapRec = ^TglBitmapNormalMapRec;
  TglBitmapNormalMapRec = record
    HalfSize : Integer;
    Func: TglBitmapNormalMapGetVectorFunc;
  end;

  //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapPosX(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := aHalfSize;
  aVec[1] := - (aPosition.Y + 0.5 - aHalfSize);
  aVec[2] := - (aPosition.X + 0.5 - aHalfSize);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapNegX(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := - aHalfSize;
  aVec[1] := - (aPosition.Y + 0.5 - aHalfSize);
  aVec[2] := aPosition.X + 0.5 - aHalfSize;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapPosY(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := aPosition.X + 0.5 - aHalfSize;
  aVec[1] := aHalfSize;
  aVec[2] := aPosition.Y + 0.5 - aHalfSize;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapNegY(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := aPosition.X + 0.5 - aHalfSize;
  aVec[1] := - aHalfSize;
  aVec[2] := - (aPosition.Y + 0.5 - aHalfSize);
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapPosZ(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := aPosition.X + 0.5 - aHalfSize;
  aVec[1] := - (aPosition.Y + 0.5 - aHalfSize);
  aVec[2] := aHalfSize;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapNegZ(out aVec: TVec; const aPosition: TglBitmapPixelPosition; const aHalfSize: Integer);
begin
  aVec[0] := - (aPosition.X + 0.5 - aHalfSize);
  aVec[1] := - (aPosition.Y + 0.5 - aHalfSize);
  aVec[2] := - aHalfSize;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glBitmapNormalMapFunc(var FuncRec: TglBitmapFunctionRec);
var
  i: Integer;
  Vec: TVec;
  Len: Single;
begin
  with FuncRec do begin
    with PglBitmapNormalMapRec(Args)^ do begin
      Func(Vec, Position, HalfSize);

      // Normalize
      Len := 1 / Sqrt(Sqr(Vec[0]) + Sqr(Vec[1]) + Sqr(Vec[2]));
      if Len <> 0 then begin
        Vec[0] := Vec[0] * Len;
        Vec[1] := Vec[1] * Len;
        Vec[2] := Vec[2] * Len;
      end;

      // Scale Vector and AddVectro
      Vec[0] := Vec[0] * 0.5 + 0.5;
      Vec[1] := Vec[1] * 0.5 + 0.5;
      Vec[2] := Vec[2] * 0.5 + 0.5;
    end;

    // Set Color
    for i := 0 to 2 do
      Dest.Data.arr[i] := Round(Vec[i] * 255);
  end;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapNormalMap.AfterConstruction;
begin
  inherited;
  fGenMode := GL_NORMAL_MAP;
end;

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TglBitmapNormalMap.GenerateNormalMap(const aSize: Integer; const aTestTextureSize: Boolean);
var
  Rec: TglBitmapNormalMapRec;
  SizeRec: TglBitmapPixelPosition;
begin
  Rec.HalfSize := aSize div 2;
  FreeDataAfterGenTexture := false;

  SizeRec.Fields := [ffX, ffY];
  SizeRec.X := aSize;
  SizeRec.Y := aSize;

  // Positive X
  Rec.Func := glBitmapNormalMapPosX;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_POSITIVE_X, aTestTextureSize);

  // Negative X
  Rec.Func := glBitmapNormalMapNegX;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_NEGATIVE_X, aTestTextureSize);

  // Positive Y
  Rec.Func := glBitmapNormalMapPosY;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_POSITIVE_Y, aTestTextureSize);

  // Negative Y
  Rec.Func := glBitmapNormalMapNegY;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, aTestTextureSize);

  // Positive Z
  Rec.Func := glBitmapNormalMapPosZ;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_POSITIVE_Z, aTestTextureSize);

  // Negative Z
  Rec.Func := glBitmapNormalMapNegZ;
  LoadFromFunc(SizeRec, glBitmapNormalMapFunc, tfBGR8, @Rec);
  GenerateCubeMap(GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, aTestTextureSize);
end;


initialization
  glBitmapSetDefaultFormat (tfEmpty);
  glBitmapSetDefaultMipmap (mmMipmap);
  glBitmapSetDefaultFilter (GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR);
  glBitmapSetDefaultWrap   (GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
  glBitmapSetDefaultSwizzle(GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA);

  glBitmapSetDefaultFreeDataAfterGenTexture(true);
  glBitmapSetDefaultDeleteTextureOnFree    (true);

  TFormatDescriptor.Init;

{$IFDEF GLB_NATIVE_OGL_DYNAMIC}
  OpenGLInitialized := false;
  InitOpenGLCS := TCriticalSection.Create;
{$ENDIF}

finalization
  TFormatDescriptor.Finalize;

{$IFDEF GLB_NATIVE_OGL_DYNAMIC}
  FreeAndNil(InitOpenGLCS);
{$ENDIF}

end.