procedure TForm1.Button1Click(Sender: TObject);
begin
  with Form1.Canvas.Pen do
  begin
    Color := clRed;
    with Memo1.Lines do
    begin
      Add('Red  := ' + IntToStr(GetRValue(Color)));
      Add('Red  := ' + IntToStr(GetGValue(Color)));
      Add('Blue := ' + IntToStr(GetBValue(Color)));
    end;
  end;
end;