OpenGLCore/uglcTypes.pas

unit uglcTypes;

{ Package:      OpenGLCore
  Prefix:       glc - OpenGL Core
  Beschreibung: diese Unit definiert Enum-Typen die OpenGL Konstanten wrappen und stellt zusätzlich
                Funktions-Wrapper zur verfügung die diese Enum-Typen als Parameter entgegen nehmen }

{$mode objfpc}{$H+}
{$MACRO ON}
{$SCOPEDENUMS ON}

interface

uses
  dglOpenGL, sysutils;

type
  TglcFace = (
    faFront = GL_FRONT,
    faBack  = GL_BACK,
    faBoth  = GL_FRONT_AND_BACK);

  TglcPolygonMode = (
    pmPoint = GL_POINT,
    pmLine  = GL_LINE,
    pmFill  = GL_FILL);

  TglcDepthFunc = (
    dfNever         = GL_NEVER,
    dfLess          = GL_LESS,
    dfEqual         = GL_EQUAL,
    dfLessEqual     = GL_LEQUAL,
    dfGreater       = GL_GREATER,
    dfNotEqual      = GL_NOTEQUAL,
    dfGreaterEqual  = GL_GEQUAL,
    dfAlways        = GL_ALWAYS);

  TglcClearBuffer = (
    cbDepthBuffer   = GL_DEPTH_BUFFER_BIT,
    cbAccumBuffer   = GL_ACCUM_BUFFER_BIT,
    cbStencilBuffer = GL_STENCIL_BUFFER_BIT,
    cbColorBuffer   = GL_COLOR_BUFFER_BIT);

  TglcTextureMinFilter = (
    mfNearest              = GL_NEAREST,
    mfLinear               = GL_LINEAR,
    mfNearestMipmapNearest = GL_NEAREST_MIPMAP_NEAREST,
    mfLinearMipmapNearest  = GL_LINEAR_MIPMAP_NEAREST,
    mfNearestMipmapLinear  = GL_NEAREST_MIPMAP_LINEAR,
    mfLinearMipmapLinear   = GL_LINEAR_MIPMAP_LINEAR);

  TglcTextureMagFilter = (
    mfNearest = GL_NEAREST,
    mfLinear  = GL_LINEAR);

  TglcTextureWrap = (
    twClamp          = GL_CLAMP,
    twRepeat         = GL_REPEAT,
    twClampToBorder  = GL_CLAMP_TO_BORDER,
    twClampToEdge    = GL_CLAMP_TO_EDGE,
    twMirroredRepeat = GL_MIRRORED_REPEAT);

  TglcBlendFactor = (
    bfZero               = GL_ZERO,
    bfOne                = GL_ONE,
    bfSrcColor           = GL_SRC_COLOR,
    bfOneMinusSrcColor   = GL_ONE_MINUS_SRC_COLOR,
    bfSrcAlpha           = GL_SRC_ALPHA,
    bfOneMinusSrcAlpha   = GL_ONE_MINUS_SRC_ALPHA,
    bfDstAlpha           = GL_DST_ALPHA,
    bfOneMinusDstAlpha   = GL_ONE_MINUS_DST_ALPHA,
    bfDstColor           = GL_DST_COLOR,
    bfOneMinusDstColor   = GL_ONE_MINUS_DST_COLOR,
    bfSrcAlphaSaturate   = GL_SRC_ALPHA_SATURATE,
    bgConstColor         = GL_CONSTANT_COLOR,
    bfOneMinusConstColor = GL_ONE_MINUS_CONSTANT_COLOR,
    bfConstAlpha         = GL_CONSTANT_ALPHA,
    bfOneMinusConstAlpha = GL_ONE_MINUS_CONSTANT_ALPHA);

  TglcBlendMode = (
    bmNone,
    bmAlphaBlend,
    bmAdditiveAlphaBlend,
    bmAdditiveBlend);

  TglcFormat = (
    fmUnknown           = 0,
    fmColorIndex        = GL_COLOR_INDEX,
    fmDepthComponent    = GL_DEPTH_COMPONENT,
    fmRed               = GL_RED,
    fmGreen             = GL_GREEN,
    fmBlue              = GL_BLUE,
    fmAlpha             = GL_ALPHA,
    fmRGB               = GL_RGB,
    fmRGBA              = GL_RGBA,
    fmLuminance         = GL_LUMINANCE,
    fmLuminanceAlpha    = GL_LUMINANCE_ALPHA,
    fmBGR               = GL_BGR,
    fmBGRA              = GL_BGRA,
    fmDepthStencil      = GL_DEPTH_STENCIL);

  TglcInternalFormat = (
    ifUnknown                   = 0,
    ifDepthComponent            = GL_DEPTH_COMPONENT,
    ifAlpha                     = GL_ALPHA,
    ifRGB                       = GL_RGB,
    ifRGBA                      = GL_RGBA,
    ifLuminance                 = GL_LUMINANCE,
    ifLuminanceAlpha            = GL_LUMINANCE_ALPHA,
    ifR3G3B2                    = GL_R3_G3_B2,
    ifAlpha4                    = GL_ALPHA4,
    ifAlpha8                    = GL_ALPHA8,
    ifAlpha12                   = GL_ALPHA12,
    ifAlpha16                   = GL_ALPHA16,
    ifLuminance4                = GL_LUMINANCE4,
    ifLuminance8                = GL_LUMINANCE8,
    ifLuminance12               = GL_LUMINANCE12,
    ifLuminance16               = GL_LUMINANCE16,
    ifLuminance4Alpha4          = GL_LUMINANCE4_ALPHA4,
    ifLuminance6Alpha2          = GL_LUMINANCE6_ALPHA2,
    ifLuminance8Alpha8          = GL_LUMINANCE8_ALPHA8,
    ifLuminance12Alpha4         = GL_LUMINANCE12_ALPHA4,
    ifLuminance12Alpha12        = GL_LUMINANCE12_ALPHA12,
    ifLuminance16Alpha16        = GL_LUMINANCE16_ALPHA16,
    ifIntensity                 = GL_INTENSITY,
    ifIntensity4                = GL_INTENSITY4,
    ifIntensity8                = GL_INTENSITY8,
    ifIntensity12               = GL_INTENSITY12,
    ifIntensity16               = GL_INTENSITY16,
    ifRGB4                      = GL_RGB4,
    ifRGB5                      = GL_RGB5,
    ifRGB8                      = GL_RGB8,
    ifRGB10                     = GL_RGB10,
    ifRGB12                     = GL_RGB12,
    ifRGB16                     = GL_RGB16,
    ifRGBA2                     = GL_RGBA2,
    ifRGBA4                     = GL_RGBA4,
    ifRGB5A1                    = GL_RGB5_A1,
    ifRGBA8                     = GL_RGBA8,
    ifRGB10A2                   = GL_RGB10_A2,
    ifRGBA12                    = GL_RGBA12,
    ifRGBA16                    = GL_RGBA16,
    ifDepthComponent16          = GL_DEPTH_COMPONENT16,
    ifDepthComponent24          = GL_DEPTH_COMPONENT24,
    ifDepthComponent32          = GL_DEPTH_COMPONENT32,
    ifCompressedAlpha           = GL_COMPRESSED_ALPHA,
    ifCompressedLuminance       = GL_COMPRESSED_LUMINANCE,
    ifCompressedLuminanceAlpha  = GL_COMPRESSED_LUMINANCE_ALPHA,
    ifCompressedIntensity       = GL_COMPRESSED_INTENSITY,
    ifCompressedRGB             = GL_COMPRESSED_RGB,
    ifCompressedRGBA            = GL_COMPRESSED_RGBA,
    ifRGBA32f                   = GL_RGBA32F,
    ifRGB32f                    = GL_RGB32F,
    ifRGBA16F                   = GL_RGBA16F,
    ifRGB16F                    = GL_RGB16F,
    ifDepth24Stencil8           = GL_DEPTH24_STENCIL8,
    ifSRGB                      = GL_SRGB,
    ifSRGB8                     = GL_SRGB8,
    ifSRGBA                     = GL_SRGB_ALPHA,
    ifSRGBA8                    = GL_SRGB8_ALPHA8,
    ifSLuminanceAlpha           = GL_SLUMINANCE_ALPHA,
    ifSLuminance8Alpha8         = GL_SLUMINANCE8_ALPHA8,
    ifSLuminance                = GL_SLUMINANCE,
    ifSLuminance8               = GL_SLUMINANCE8,
    ifDepth32fStencil8          = GL_DEPTH32F_STENCIL8,
    ifStencil1                  = GL_STENCIL_INDEX1,
    ifStencil4                  = GL_STENCIL_INDEX4,
    ifStencil8                  = GL_STENCIL_INDEX8,
    ifStencil16                 = GL_STENCIL_INDEX16);

  TglcAttachment = (
    atDepthStencil = GL_DEPTH_STENCIL_ATTACHMENT,
    atColor0       = GL_COLOR_ATTACHMENT0,
    atColor1       = GL_COLOR_ATTACHMENT1,
    atColor2       = GL_COLOR_ATTACHMENT2,
    atColor3       = GL_COLOR_ATTACHMENT3,
    atColor4       = GL_COLOR_ATTACHMENT4,
    atColor5       = GL_COLOR_ATTACHMENT5,
    atColor6       = GL_COLOR_ATTACHMENT6,
    atColor7       = GL_COLOR_ATTACHMENT7,
    atColor8       = GL_COLOR_ATTACHMENT8,
    atColor9       = GL_COLOR_ATTACHMENT9,
    atColor10      = GL_COLOR_ATTACHMENT10,
    atColor11      = GL_COLOR_ATTACHMENT11,
    atColor12      = GL_COLOR_ATTACHMENT12,
    atColor13      = GL_COLOR_ATTACHMENT13,
    atColor14      = GL_COLOR_ATTACHMENT14,
    atColor15      = GL_COLOR_ATTACHMENT15,
    atDepth        = GL_DEPTH_ATTACHMENT,
    atStencil      = GL_STENCIL_ATTACHMENT);

  TglcShaderType = (
    stFragment        = GL_FRAGMENT_SHADER,
    stVertex          = GL_VERTEX_SHADER,
    stGeometry        = GL_GEOMETRY_SHADER,
    stTessEvaluation  = GL_TESS_EVALUATION_SHADER,
    stTessControl     = GL_TESS_CONTROL_SHADER);

  TglcBufferTarget = (
    btArrayBuffer        = GL_ARRAY_BUFFER,
    btElementArrayBuffer = GL_ELEMENT_ARRAY_BUFFER);

  TglcBufferUsage = (
    buStreamDraw  = GL_STREAM_DRAW,
    buStreamRead  = GL_STREAM_READ,
    buStreamCopy  = GL_STREAM_COPY,
    buStaticDraw  = GL_STATIC_DRAW,
    buStaticRead  = GL_STATIC_READ,
    buStaticCopy  = GL_STATIC_COPY,
    buDynamicDraw = GL_DYNAMIC_DRAW,
    buDynamicRead = GL_DYNAMIC_READ,
    buDynamicCopy = GL_DYNAMIC_COPY);

  TglcBufferAccess = (
    baReadOnly  = GL_READ_ONLY,
    baWriteOnly = GL_WRITE_ONLY,
    baReadWrite = GL_READ_WRITE);

  EOpenGL = class(Exception)
  private
    fErrorCode: GLenum;
  public
    property ErrorCode: GLenum read fErrorCode;
    constructor Create(const aErrorCode: GLenum);
    constructor Create(const aMsg: String; const aErrorCode: GLenum);
  end;

procedure glcRenderFace(const aValue: TglcFace); inline;
procedure glcPolygonMode(const aFace: TglcFace; const aValue: TglcPolygonMode); inline;
procedure glcDepthFunc(const aValue: TglcDepthFunc); inline;
procedure glcBlendFunc(const aSource, aDest: TglcBlendFactor); inline; overload;
procedure glcBlendFunc(const aMode: TglcBlendMode); inline; overload;
procedure glcCheckAndRaiseError;

implementation

type
  TglcBlendModeValue = packed record
    src, dst: TglcBlendFactor;
  end;

const
  BLEND_MODE_VALUES: array[TglcBlendMode] of TglcBlendModeValue = (
    (src: TglcBlendFactor.bfOne;         dst: TglcBlendFactor.bfZero),                        //bmNone
    (src: TglcBlendFactor.bfSrcAlpha;    dst: TglcBlendFactor.bfOneMinusSrcAlpha),            //bmAlphaBlend
    (src: TglcBlendFactor.bfSrcAlpha;    dst: TglcBlendFactor.bfOne),                         //bmAdditiveAlphaBlend
    (src: TglcBlendFactor.bfOne;         dst: TglcBlendFactor.bfOne));                        //bmAdditiveBlend

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcRenderFace(const aValue: TglcFace);
begin
  case aValue of
    TglcFace.faBoth: begin
      glDisable(GL_CULL_FACE);
    end;
    TglcFace.faFront: begin
      glEnable(GL_CULL_FACE);
      glCullFace(GL_BACK);
    end;
    TglcFace.faBack: begin
      glEnable(GL_CULL_FACE);
      glCullFace(GL_FRONT);
    end;
  end;
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcPolygonMode(const aFace: TglcFace; const aValue: TglcPolygonMode);
begin
  glPolygonMode(GLenum(aFace), GLenum(aValue));
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcDepthFunc(const aValue: TglcDepthFunc);
begin
  glDepthFunc(GLenum(aValue));
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcBlendFunc(const aSource, aDest: TglcBlendFactor);
begin
  glBlendFunc(GLenum(aSource), GLenum(aDest));
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcBlendFunc(const aMode: TglcBlendMode); overload;
begin
  glBlendFunc(GLenum(BLEND_MODE_VALUES[aMode].src), GLenum(BLEND_MODE_VALUES[aMode].dst));
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure glcCheckAndRaiseError;
var
  e: GLenum;
begin
  e := glGetError();
  if (e <> GL_NO_ERROR) then
    raise EOpenGL.Create(e);
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//EOpenGL///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor EOpenGL.Create(const aErrorCode: GLenum);
begin
  fErrorCode := aErrorCode;
  inherited Create(gluErrorString(fErrorCode));
end;

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
constructor EOpenGL.Create(const aMsg: String; const aErrorCode: GLenum);
begin
  fErrorCode := aErrorCode;
  inherited Create(aMsg + ': ' + gluErrorString(fErrorCode))
end;

end.