unit uvkuDescriptorSetLayoutFactory;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils,
  Vulkan, uvkuFactoryBase, uvkuDescriptorSetLayout, uvkuTypes;

type
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TvkuDescriptorSetLayoutBinding = class(TvkuStructure)
  private
    fImmutableSamplers: TVkSamplerList;
  public
    Binding:            VkUint32;
    DescriptorType:     TVkDescriptorType;
    DescriptorCount:    VkUint32;
    StageFlags:         VkShaderStageFlags;

    property ImmutableSamplers: TVkSamplerList read fImmutableSamplers;

    function GetStructure: TVkDescriptorSetLayoutBinding;
    procedure SetStructure(const aData: TVkDescriptorSetLayoutBinding);

    procedure AfterConstruction; override;
    procedure BeforeDestruction; override;
  end;
  TvkuDescriptorSetLayoutBindingArr = specialize TvkuObjList<TvkuDescriptorSetLayoutBinding>;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
  TvkuDescriptorSetLayoutFactory = class(TvkuDeviceObjFactory)
  private
    fFlags: VkDescriptorSetLayoutCreateFlags;
    fBindings: TvkuDescriptorSetLayoutBindingArr;

    fvkBindings: TVkDescriptorSetLayoutBindingArr;
  public
    property Flags:    VkDescriptorSetLayoutCreateFlags  read fFlags write fFlags;
    property Bindings: TvkuDescriptorSetLayoutBindingArr read fBindings;

    function GetStructure: TVkDescriptorSetLayoutCreateInfo;
    procedure SetStructure(const aData: TVkDescriptorSetLayoutCreateInfo);

    function CreateDescriptorSetLayout: TvkuDescriptorSetLayout;

    procedure AfterConstruction; override;
    procedure BeforeDestruction; override;
  end;

implementation

uses
  uvkuUtils;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TvkuDescriptorSetLayoutBinding/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TvkuDescriptorSetLayoutBinding.GetStructure: TVkDescriptorSetLayoutBinding;
begin
  FillByte(result, SizeOf(result), 0);
  result.binding            := Binding;
  result.descriptorType     := DescriptorType;
  result.descriptorCount    := DescriptorCount;
  result.stageFlags         := StageFlags;
  result.pImmutableSamplers := fImmutableSamplers.PData;

  if (fImmutableSamplers.Length <> 0) and
     (fImmutableSamplers.Length <> DescriptorCount) then
     raise TvkuException.Create('''ImmutableSamplers'' must be either empty or contains ''DescriptorCount'' number of elements');
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutBinding.SetStructure(const aData: TVkDescriptorSetLayoutBinding);
var i: Integer;
begin
  Binding         := aData.binding;
  DescriptorType  := aData.descriptorType;
  StageFlags      := aData.stageFlags;
  fImmutableSamplers.SetData(aData.pImmutableSamplers, aData.descriptorCount);
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutBinding.AfterConstruction;
begin
  inherited AfterConstruction;
  fImmutableSamplers := TVkSamplerList.Create;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutBinding.BeforeDestruction;
begin
  FreeAndNil(fImmutableSamplers);
  inherited BeforeDestruction;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//TvkuDescriptorSetLayoutFactory/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TvkuDescriptorSetLayoutFactory.GetStructure: TVkDescriptorSetLayoutCreateInfo;
var i: Integer;
begin
  SetLength(fvkBindings, fBindings.Length);
  for i := low(fvkBindings) to high(fvkBindings) do
    fvkBindings[i] := fBindings[i].GetStructure;

  FillByte(result, SizeOf(result), 0);
  result.sType        := VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO;
  result.pNext        := nil;
  result.flags        := fFlags;
  result.bindingCount := Length(fvkBindings);
  result.pBindings    := @fvkBindings[0];
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutFactory.SetStructure(const aData: TVkDescriptorSetLayoutCreateInfo);
var i: Integer;
begin
  fFlags := aData.flags;
  fBindings.Length := aData.bindingCount;
  for i := 0 to fBindings.Length do
    fBindings[i].SetStructure((aData.pBindings + i)^);
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function TvkuDescriptorSetLayoutFactory.CreateDescriptorSetLayout: TvkuDescriptorSetLayout;
begin
  result := TvkuDescriptorSetLayout.Create(GetStructure, DeviceCommands, AllocCallbacks);
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutFactory.AfterConstruction;
begin
  inherited AfterConstruction;
  fBindings := TvkuDescriptorSetLayoutBindingArr.Create;
end;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
procedure TvkuDescriptorSetLayoutFactory.BeforeDestruction;
begin
  FreeAndNil(fBindings);
  inherited BeforeDestruction;
end;

end.