Rotation flackert

[Destroxi]

Hallo,
wenn ich Versuche, mein TexQuad zu drehen (opengl) flackert es dauernt und dreht sich nicht ...
Was kann ich tun?

Code:

Delphi-Quellcode:

// Quad zeichnen
procedure DrawObject(X, Y, aType: Integer; Moving: Boolean);
begin
 If not Moving then BlockBool(X, Y, aType);
 glRotatef(90, 0, 0, 1); // Test-Drehung
 glBindTexture(GL_TEXTURE_2D, Blocks[aType]);
 glBegin(GL_QUADS);
  glTexCoord2f(0+(1/(TexSize[aType].X*24+2)), 0+(1/(TexSize[aType].Y*24+2))); glVertex2f(X, Y);
  glTexCoord2f(1-(1/(TexSize[aType].X*24+2)), 0+(1/(TexSize[aType].Y*24+2))); glVertex2f(X+BlockSize*TexSize[aType].X, Y);
  glTexCoord2f(1-(1/(TexSize[aType].X*24+2)), 1-(1/(TexSize[aType].Y*24+2))); glVertex2f(X+BlockSize*TexSize[aType].X, Y+BlockSize*TexSize[aType].Y);
  glTexCoord2f(0+(1/(TexSize[aType].X*24+2)), 1-(1/(TexSize[aType].Y*24+2))); glVertex2f(X, Y+BlockSize*TexSize[aType].Y);
 glEnd;     
 glBlendFunc(GL_SRC_ALPHA, GL_DST_ALPHA);
end;
// Render Code [ist im OnIdle der App]
procedure TMainForm.Render(Sender: TObject; var Done: Boolean);
var
 i, i1, i2: Integer;
begin
 Done := False;

 glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT);
 
 For i1 := 0 to FieldSize do
  For i2 := 0 to FieldSize do
   BlockLines[i1][i2] := False;

 If High(Objects)-1 > Low(Objects) then
  For i := Low(Objects)+1 to High(Objects)-1 do
   DrawObject(Objects[i].X, Objects[i].Y, Objects[i].aType, False);
 If High(Objects) > Low(Objects) then
  DrawObject(Objects[High(Objects)].X, Objects[High(Objects)].Y, Objects[High(Objects)].aType, True);

 SwapBuffers(DC);
end;

Destroxi