unit fMultiTextures;

interface

uses
  Winapi.Windows,
  Winapi.OpenGL,
  System.SysUtils,
  System.Classes,
  Vcl.Controls,
  Vcl.Forms,
  Vcl.Dialogs,
  Vcl.StdCtrls,
  Vcl.ExtCtrls,

  
  GLS.Scene,
  GLS.Objects,
  GLS.SceneViewer,
 
  GLS.Coordinates,
  GLS.BaseClasses,
  GLS.BitmapFont,
  GLS.WindowsFont,
  GLSL.Shader,
  GLSL.CustomShader,
  GLS.Material,
  GLS.Cadencer,
  GLS.HUDObjects,
  GLS.GeomObjects,
  GLS.FBORenderer,
  GLS.VectorGeometry,
  GLS.VectorTypes,
  GLS.Texture,
  GLS.SimpleNavigation,
  GLS.State,
  GLS.Context,
  GLS.Keyboard,
  GLS.MultiSampleImage;

type
  TFormMultiSampleTextures = class(TForm)
    MainScene: TGLScene;
    MainCamera: TGLCamera;
    MainCadencer: TGLCadencer;
    MainMaterialLibrary: TGLMaterialLibrary;
    SceneObjects: TGLDummyCube;
    MainViewer: TGLSceneViewer;
    TestLight: TGLLightSource;
    MultisampleFBO: TGLFBORenderer;
    GLSLShader1: TGLSLShader;
    GLSimpleNavigation1: TGLSimpleNavigation;
    GLScreenQuad: TGLHUDSprite;
    GLSphere1: TGLSphere;
    GLTorus1: TGLTorus;
    GLTorus2: TGLTorus;
    GLCone1: TGLCone;
    GLLines1: TGLLines;
    FBOContainer: TGLDummyCube;
    GLHUDText1: TGLHUDText;
    GLWindowsBitmapFont1: TGLWindowsBitmapFont;
    procedure FormCreate(Sender: TObject);
    procedure MainCadencerProgress(Sender: TObject; const deltaTime, newTime: Double);
    procedure FormResize(Sender: TObject);
    procedure GLSLShader1Apply(Shader: TGLCustomGLSLShader);
    procedure MainViewerBeforeRender(Sender: TObject);
  end;

var
  FormMultiSampleTextures: TFormMultiSampleTextures;

implementation

{$R *.dfm}

procedure TFormMultiSampleTextures.FormCreate(Sender: TObject);
begin

  MainMaterialLibrary.TextureByName('MultisampledColor').ImageClassName := 'TGLMultisampleImage';
  TGLMultiSampleImage(MainMaterialLibrary.TextureByName('MultisampledColor').Image).SamplesCount := 16;

  MainMaterialLibrary.TextureByName('Depth').ImageClassName := 'TGLMultisampleImage';
  TGLMultiSampleImage(MainMaterialLibrary.TextureByName('Depth').Image).SamplesCount := 16;

  GLSLShader1.Enabled := True;

  GLHUDText1.Text := 'Press F1/F2 to switch multisampling' + #10#13 +
                     'F3/F4 - Wireframe mode';
end;

procedure TFormMultiSampleTextures.MainCadencerProgress(Sender: TObject; const deltaTime,
  newTime: Double);
begin
  if IsKeyDown(VK_F2) then
  begin
    FBOContainer.Visible := false;
    GLScreenQuad.Visible := false;
    SceneObjects.Visible := true;
  end;

  if IsKeyDown(VK_F1) then
  begin
    FBOContainer.Visible := true;
    GLScreenQuad.Visible := true;
    SceneObjects.Visible := false;
  end;

  if IsKeyDown(VK_F3) then
  begin
    GLTorus1.Material.PolygonMode := pmLines;
    GLTorus2.Material.PolygonMode := pmLines;
    GLCone1.Material.PolygonMode := pmLines;
  end;

  if IsKeyDown(VK_F4) then
  begin
    GLTorus1.Material.PolygonMode := pmFill;
    GLTorus2.Material.PolygonMode := pmFill;
    GLCone1.Material.PolygonMode := pmFill;
  end;

  MainViewer.Invalidate();
end;

procedure TFormMultiSampleTextures.FormResize(Sender: TObject);
begin
  MultisampleFBO.Width := MainViewer.Width;
  MultisampleFBO.Height := MainViewer.Height;
  GLScreenQuad.Width  := MainViewer.Width;
  GLScreenQuad.Height := MainViewer.Height;
  GLScreenQuad.Position.SetPoint(
    MainViewer.Width div 2,
    MainViewer.Height div 2, 0);
end;

procedure TFormMultiSampleTextures.GLSLShader1Apply(Shader: TGLCustomGLSLShader);
begin
  Shader.Param['TexUnit0'].AsTexture[0] :=
     MainMaterialLibrary.TextureByName('MultisampledColor');
  Shader.Param['ViewerSize'].AsVector2f :=
     Vector2fMake(MainViewer.Width, MainViewer.Height);
end;

procedure TFormMultiSampleTextures.MainViewerBeforeRender(Sender: TObject);
begin
  if not gl.EXT_framebuffer_multisample then
  begin
    ShowMessage
      ('Sorry, your hardware do not support Multisampling');
    Close;
  end;
end;

end.