anchor.diff:  
   implementation
   
  -
   function SetDCPixelFormat(h_DC:HDC; PixelFormat:Integer):boolean;
   var
     nPixelFormat: Integer;
     PixelDepth:integer;
  +  {$IFDEF MSWINDOWS}
     pfd: TPixelFormatDescriptor;
  +  {$ENDIF}
   begin
     PixelDepth := 32; //32bpp is common
  -
  +  {$IFDEF MSWINDOWS}
     with pfd do begin
       nSize           := SizeOf(TPIXELFORMATDESCRIPTOR); // Size Of This Pixel Format Descriptor
       nVersion        := 1;                    // The version of this data structure
  
positive.code:   //Try to find mode with slightly worse AA before giving up
    repeat
      iAttributes[19] := AntiAliasing;
      ValidFormat := wglChoosePixelFormatARB(h_dc, @iattributes[0], nil, 1, @pixelFormat, @NumFormats);
      if ValidFormat and (NumFormats >= 1) then
      begin
        Result := pixelFormat;
  
negative.code:   end;
  
    Result := true;
    {$ENDIF}
    //glXChooseVisual() should be on Uni insted of ChoosePixelFormatx
  end;
  
  
  