procedure GraphicToBitmap(const Src: Graphics.TGraphic;
  const Dest: Graphics.TBitmap; const TransparentColor: Graphics.TColor);
begin
  // Do nothing if either source or destination are nil
  if not Assigned(Src) or not Assigned(Dest) then
    Exit;
  // Size the bitmap
  Dest.Width := Src.Width;
  Dest.Height := Src.Height;
  if Src.Transparent then
  begin
    // Source graphic is transparent, make bitmap behave transparently
    Dest.Transparent := True;
    if (TransparentColor <> Graphics.clNone) then
    begin
      // Set destination as transparent using required colour key
      Dest.TransparentColor := TransparentColor;
      Dest.TransparentMode := Graphics.tmFixed;
      // Set background colour of bitmap to transparent colour
      Dest.Canvas.Brush.Color := TransparentColor;
    end
    else
      // No transparent colour: set transparency to automatic
      Dest.TransparentMode := Graphics.tmAuto;
  end;
  // Clear bitmap to required background colour and draw bitmap
  Dest.Canvas.FillRect(Classes.Rect(0, 0, Dest.Width, Dest.Height));
  Dest.Canvas.Draw(0, 0, Src);
end;
//delphi/2248