teeglcanvas.pas

第三方控件：PaintGrid.pas 网格型仪表控件源文件 Mymeter.pas 圆型仪表控件源文件 Project1是这两个控件的使用范例。 该

  Assert(CheckGLError,'Rotations');

  if ShadeQuality then gluQuadricNormals(Quadric,GL_SMOOTH)
                  else gluQuadricNormals(Quadric,GL_FLAT);

  Assert(CheckGLError,'QuadricNormals');

  if Assigned(FOnInit) then FOnInit(Self);
  Assert(CheckGLError,'Init');
end;

Function TGLCanvas.Quadric:PGLUQuadricObj; {$IFDEF CLR}unsafe;{$ENDIF}
begin
  if not Assigned(FQuadric) then
     FQuadric:=gluNewQuadric;

  result:=FQuadric;
end;

Procedure TGLCanvas.TeeVertex2D(x,y:Integer);
begin
  glVertex2i(x,-y);
end;

Procedure TGLCanvas.TeeVertex3D(x,y,z:Integer);
begin
  glVertex3i(x,-y,-z);
end;

Procedure TGLCanvas.TeeNormal(x,y,z:Integer);
begin
  glNormal3i(x,y,-z);
end;

Procedure TGLCanvas.SetBrushBitmap;
begin
  SetBrushBitmap(Brush.Bitmap);
end;

Function TGLCanvas.SetBrushBitmap(Bitmap:TBitmap):Boolean;
var tmp : Cardinal;
begin
  if Bitmap<>nil then
  begin
    tmp:=FindTexture(Bitmap);

    result:=tmp<>0;

    if result then
    begin
      glEnable(GL_TEXTURE_2D);

      {$IFNDEF LINUX}
      glBindTexture(GL_TEXTURE_2D, tmp);
      Assert(CheckGLError,'BindTexture');
      {$ENDIF}

      gluQuadricTexture(Quadric,{$IFDEF LINUX}True{$ELSE}GL_TRUE{$ENDIF});
      Assert(CheckGLError,'gluQuadricTexture');
      IQuadricTexture:=True;

      glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
    end;

  end
  else result:=True;
end;

Procedure TGLCanvas.EndBrushBitmap;
begin
  EndBrushBitmap(Brush.Bitmap);
end;

Procedure TGLCanvas.EndBrushBitmap(Bitmap:TBitmap);
begin
  if Bitmap<>nil then
  begin
    if IQuadricTexture then
    begin
      gluQuadricTexture(Quadric,{$IFDEF LINUX}False{$ELSE}GL_FALSE{$ENDIF});
      Assert(CheckGLError,'gluQuadricTexture');
      IQuadricTexture:=False;
    end;

    glDisable(GL_TEXTURE_2D);
  end;
end;

Procedure TGLCanvas.Cube(Left,Right,Top,Bottom,Z0,Z1:Integer; DarkSides:Boolean);
begin
  glEnable(GL_CULL_FACE);

  if Left>Right then SwapInteger(Left,Right);
  if Top>Bottom then SwapInteger(Top,Bottom);
  if z0>z1 then SwapInteger(z0,z1);

  if Brush.Style<>bsClear then
  begin
    SetColor(Brush.Color);
    SetBrushBitmap;

    glBegin(GL_QUADS);
    TeeNormal( 0, 0, -1);
     glTexCoord2f(1,0);
     TeeVertex3D( Left,  Bottom, z0);
     glTexCoord2f(1,1);
     TeeVertex3D( Right, Bottom, z0);
     glTexCoord2f(0,1);
     TeeVertex3D( Right, Top,    z0);
     glTexCoord2f(0,0);
     TeeVertex3D( Left,  Top,    z0);

    TeeNormal(-1,  0,  0);
     glTexCoord2f(0,0);
     TeeVertex3D( Left, Top,    z1);
     glTexCoord2f(0,1);
     TeeVertex3D( Left, Bottom, z1);
     glTexCoord2f(1,1);
     TeeVertex3D( Left, Bottom, z0);
     glTexCoord2f(1,0);
     TeeVertex3D( Left, Top,    z0);

    TeeNormal( 0, 0, 1);
     glTexCoord2f(0,0);
     TeeVertex3D( Right, Top,    z1);
     glTexCoord2f(0,1);
     TeeVertex3D( Right, Bottom, z1);
     glTexCoord2f(1,1);
     TeeVertex3D( Left,  Bottom, z1);
     glTexCoord2f(1,0);
     TeeVertex3D( Left,  Top,    z1);

    TeeNormal( 1,  0,  0);
     glTexCoord2f(0,0);
     TeeVertex3D( Right, Bottom, z0);
     glTexCoord2f(0,1);
     TeeVertex3D( Right, Bottom, z1);
     glTexCoord2f(1,1);
     TeeVertex3D( Right, Top,    z1);
     glTexCoord2f(1,0);
     TeeVertex3D( Right, Top,    z0);

    TeeNormal( 0, 1,  0);
     glTexCoord2f(0,0);
     TeeVertex3D( Left,  Top, z1);
     glTexCoord2f(0,1);
     TeeVertex3D( Left,  Top, z0);
     glTexCoord2f(1,1);
     TeeVertex3D( Right, Top, z0);
     glTexCoord2f(1,0);
     TeeVertex3D( Right, Top, z1);

    TeeNormal( 0, -1,  0);
     glTexCoord2f(0,0);
     TeeVertex3D( Right, Bottom, z0);
     glTexCoord2f(0,1);
     TeeVertex3D( Left,  Bottom, z0);
     glTexCoord2f(1,1);
     TeeVertex3D( Left,  Bottom, z1);
     glTexCoord2f(1,0);
     TeeVertex3D( Right, Bottom, z1);

    glEnd;
    EndBrushBitmap;
  end;

  if Pen.Style<>psClear then
  begin
    SetPen;
    glBegin(GL_LINE_LOOP);
      TeeVertex3D( Left,  Bottom, z0);
      TeeVertex3D( Right, Bottom, z0);
      TeeVertex3D( Right, Top,    z0);
      TeeVertex3D( Left,  Top,    z0);
    glEnd;

    glBegin(GL_LINE_LOOP);
      TeeVertex3D( Left,  Top,    z1);
      TeeVertex3D( Left,  Bottom, z1);
      TeeVertex3D( Right, Bottom, z1);
      TeeVertex3D( Right, Top,    z1);
    glEnd;

    glBegin(GL_LINE_LOOP);
      TeeVertex3D( Right, Top,    z0);
      TeeVertex3D( Right, Top,    z1);
      TeeVertex3D( Right, Bottom, z1);
      TeeVertex3D( Right, Bottom, z0);
    glEnd;

    glBegin(GL_LINE_LOOP);
      TeeVertex3D( Left, Top,    z0);
      TeeVertex3D( Left, Bottom, z0);
      TeeVertex3D( Left, Bottom, z1);
      TeeVertex3D( Left, Top,    z1);
    glEnd;

    glBegin(GL_LINE_LOOP);
      TeeVertex3D( Right, Top, z1);
      TeeVertex3D( Right, Top, z0);
      TeeVertex3D( Left,  Top, z0);
      TeeVertex3D( Left,  Top, z1);
    glEnd;
  end;

  glDisable(GL_CULL_FACE);
  Assert(CheckGLError,'Cube');
end;

Procedure TGLCanvas.SetMaterialColor; {$IFDEF CLR}unsafe;{$ENDIF}

  Function GLColor(Const Value:Double):GLMat;
  begin
    result[0]:=Value;
    result[1]:=Value;
    result[2]:=Value;
    result[3]:=1;
  end;

var tmp : GLMat;
begin
  tmp:=GLColor(TeeMaterialDiffuse);
  glMaterialfv(TeeColorPlanes,GL_DIFFUSE,PGLFloat(@tmp));
  tmp:=GLColor(TeeMaterialSpecular);
  glMaterialfv(TeeColorPlanes,GL_SPECULAR,PGLFloat(@tmp));
  tmp:=GLColor(TeeMaterialAmbient);
  glMaterialfv(TeeColorPlanes,GL_AMBIENT,PGLFloat(@tmp));
  Assert(CheckGLError,'Material '+IntToStr(FSavedError));
end;

{$IFNDEF LINUX}
Function TGLCanvas.GetDCHandle:HDC;
begin
  {$IFDEF CLX}
  result:=GetDC(GetActiveWindow);
  {$ELSE}
  result:=FDC;
  {$ENDIF}
end;
{$ENDIF}

Function TGLCanvas.InitWindow( DestCanvas:TCanvas;
                               A3DOptions:TView3DOptions;
                               ABackColor:TColor;
                               Is3D:Boolean;
                               Const UserRect:TRect):TRect;

begin
  FBounds:=UserRect;
  RectSize(Bounds,FWidth,FHeight);

  if Assigned(A3DOptions) then
     FontZoom:=A3DOptions.FontZoom;

  if (IDestCanvas<>DestCanvas) or (View3DOptions<>A3DOptions) then
  begin
    IDestCanvas:=DestCanvas;
    View3DOptions:=A3DOptions;

    InitOpenGL;

    DestroyGLContext;

    FDC:=DestCanvas.Handle;

    {$IFNDEF LINUX}

    {$IFDEF CLX}
    IDrawToBitmap:=False;
    {$ELSE}
    IDrawToBitmap:=GetObjectType(FDC) = OBJ_MEMDC;

    if IDrawToBitmap then  // 7.02
       DeleteTextures;
    {$ENDIF}

    if UseBuffer then
       HRC:=CreateRenderingContext(GetDCHandle,[opDoubleBuffered],24,1)  // 7.0
    else
       HRC:=CreateRenderingContext(GetDCHandle,[],24,1);  // 7.0

    if HRC=0 then Exit;

    ActivateRenderingContext(GetDCHandle,HRC);
    Assert(CheckGLError,'ActivateContext');
    {$ENDIF}

    glEnable(GL_NORMALIZE);
    Assert(CheckGLError,'EnableNormalize');

    glEnable(GL_DEPTH_TEST);
    Assert(CheckGLError,'EnableDepth');
    glDepthFunc(GL_LESS);
    Assert(CheckGLError,'DepthFunc');

    glEnable(GL_LINE_STIPPLE);
    Assert(CheckGLError,'EnableLineStipple');

    glEnable(GL_COLOR_MATERIAL);
    Assert(CheckGLError,'EnableColorMaterial');

    glColorMaterial(TeeColorPlanes,GL_AMBIENT_AND_DIFFUSE);
    Assert(CheckGLError,'ColorMaterial');

    SetMaterialColor;

    {$IFNDEF LINUX}
    //glEnable(GL_POLYGON_OFFSET_LINE);
    glEnable(GL_POLYGON_OFFSET_FILL);
    glPolygonOffset(0.5,1);

    Assert(CheckGLError,'PolygonOffset');
    {$ENDIF}

    // Enable / Disable antialias smoothing:
    if TeeSmooth then
    begin
      glEnable(GL_POLYGON_SMOOTH);
      glEnable(GL_POINT_SMOOTH);
      glEnable(GL_LINE_SMOOTH);
      glEnable(GL_BLEND);
      glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
    end
    else
    begin
      glDisable(GL_POLYGON_SMOOTH);
      glDisable(GL_POINT_SMOOTH);
      glDisable(GL_LINE_SMOOTH);
      glDisable(GL_BLEND);
    end;

    glDisable(GL_CULL_FACE);

    glEnable(GL_DITHER);
    Assert(CheckGLError,'Dither');

    glHint(GL_PERSPECTIVE_CORRECTION_HINT, TeePerspectiveQuality);
    glHint(GL_LINE_SMOOTH_HINT, TeeSmoothQuality);
    glHint(GL_POINT_SMOOTH_HINT, TeeSmoothQuality);
    glHint(GL_POLYGON_SMOOTH_HINT, TeeSmoothQuality);

    glLightModelf(GL_LIGHT_MODEL_TWO_SIDE,TeeFullLightModel);
    glLightModelf(GL_LIGHT_MODEL_LOCAL_VIEWER,TeeLightLocal);

    Assert(CheckGLError,'LightModel');
  end;

  FX:=0;
  FY:=0;
  FIs3D:=Is3D;

  {$IFNDEF LINUX}
  if GetObjectType(GetDCHandle) <> OBJ_MEMDC then
  begin
    FDC:=DestCanvas.Handle;

    ActivateRenderingContext(GetDCHandle,HRC);
  end;
  {$ENDIF}

  SetCanvas(DestCanvas);
  FBackColor:=ABackColor;
  result:=UserRect;
end;

Procedure TGLCanvas.InitAmbientLight(AmbientLight:Integer); {$IFDEF CLR}unsafe;{$ENDIF}
var tmp:GLMat;
    tmpNum:Double;
begin
  glDisable(GL_LIGHTING);
  glDisable(GL_LIGHT0);
  glDisable(GL_LIGHT1);
  glDisable(GL_LIGHT2);
  Assert(CheckGLError,'DisableLight');

  if AmbientLight>0 then
  begin
    glEnable(GL_LIGHTING);
    Assert(CheckGLError,'EnableLight');
    tmpNum:=AmbientLight*0.01;
    tmp[0]:=tmpNum;
    tmp[1]:=tmpNum;
    tmp[2]:=tmpNum;
    tmp[3]:=1;
    glLightModelfv(GL_LIGHT_MODEL_AMBIENT,  PGLFloat(@tmp));

    Assert(CheckGLError,'LightModel');
  end
  else
  begin
    tmp[0]:=0;
    tmp[1]:=0;
    tmp[2]:=0;
    tmp[3]:=1;

    glEnable(GL_LIGHTING);
    glLightModelfv(GL_LIGHT_MODEL_AMBIENT, PGLFloat(@tmp));
    Assert(CheckGLError,'LightModel');
    glDisable(GL_LIGHTING);
    Assert(CheckGLError,'DisableLightModel');
  end;
end;

Procedure TGLCanvas.SetShininess(Const Value:Double);
begin
  glMateriali(TeeColorPlanes, GL_SHININESS, Round(128.0*Value));
  Assert(CheckGLError,'Shininess');
end;

Procedure TGLCanvas.InitLight(Num:Integer; Const AColor:GLMat;
                              const Position,Direction:TPoint3DFloat;
                              UseDirection:Boolean;
                              const SpotDegrees:Double); {$IFDEF CLR}unsafe;{$ENDIF}

  procedure AssertLight(const Text:String);
  begin
    Assert(CheckGLError,Text+' '+IntToStr(Num));
  end;

Const tmpSpec=0.99;
      tmpDif =0.99;
      tmpAmb =0.1;
var tmp : GLMat;
begin
  glEnable(GL_LIGHTING);
  glEnable(Num);
  AssertLight('EnableLight');

  tmp[0]:=tmpAmb;
  tmp[1]:=tmpAmb;
  tmp[2]:=tmpAmb;
  tmp[3]:=1;
  tmp:=AColor;
  glLightfv(Num,GL_AMBIENT, PGLFloat(@tmp));
  AssertLight('LightAmbient');

  tmp[0]:=tmpDif;
  tmp[1]:=tmpDif;
  tmp[2]:=tmpDif;
  tmp[3]:=1;
  glLightfv(Num,GL_DIFFUSE, PGLFloat(@tmp));
  AssertLight('LightDiffuse');

  tmp[0]:=tmpSpec;
  tmp[1]:=tmpSpec;
  tmp[2]:=tmpSpec;
  tmp[3]:=1;
  glLightfv(Num,GL_SPECULAR, PGLFloat(@tmp));
  AssertLight('LightSpecular');

  tmp[0]:=  Position.X;
  tmp[1]:= -Position.Y;
  tmp[2]:= -Position.Z;
  tmp[3]:=1;
  glLightfv(Num,GL_POSITION, PGLFloat(@tmp));
  AssertLight('LightPosition');

  if UseDirection then
  begin
    tmp[0]:=  Direction.X;
    tmp[1]:= -Direction.Y;
    tmp[2]:= -Direction.Z;
  end
  else
  begin
    tmp[0]:=0;
    tmp[1]:=0;
    tmp[2]:=1;
  end;

  tmp[3]:=0;

  glLightfv(Num,GL_SPOT_DIRECTION, PGLFloat(@tmp));
  AssertLight('LightDirection');

  if SpotDegrees=180 then
     glLightf(Num,GL_SPOT_CUTOFF,TeeDefaultLightSpot)
  else
     glLightf(Num,GL_SPOT_CUTOFF,SpotDegrees);

  AssertLight('LightSpot');
end;

Procedure TGLCanvas.ShowImage(DestCanvas,DefaultCanvas:TCanvas; Const UserRect:TRect);
begin
  glFlush;
  Assert(CheckGLError,'Flush');

  {$IFNDEF LINUX}
  SwapBuffers(GetDCHandle);
  {$ENDIF}

  SetCanvas(DefaultCanvas);
  Assert(CheckGLError,'ShowImage');

  if IDrawToBitmap then  // 7.02
     DeleteTextures;
end;

Function TGLCanvas.ReDrawBitmap:Boolean;
begin
  result:=False;
end;

procedure TGLCanvas.Rectangle(X0,Y0,X1,Y1:Integer);
begin
  if Brush.Style<>bsClear then
     FillRect(TeeRect(X0,Y0,X1,Y1));

  if Pen.Style<>psClear then
  begin
    SetPen;
    glBegin(GL_LINE_LOOP);
    TeeVertex2D(X0,Y0);
    TeeVertex2D(X1,Y0);
    TeeVertex2D(X1,Y1);
    TeeVertex2D(X0,Y1);
    glEnd;
  end;

  Assert(CheckGLError,'Rectangle');
end;

procedure TGLCanvas.SetTextAlign(Align:Integer);
begin
  FTextAlign:=Align;
end;

procedure TGLCanvas.MoveTo(X, Y: Integer);
begin
  FX:=X;
  FY:=Y;
end;