unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls;

type
  TForm1 = class(TForm)
    Image1: TImage;
    Timer1: TTimer;
    procedure FormCreate(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
  private
    { Private declarations } 
  public
    { Public declarations } 
  end;

var
  Form1 : TForm1;
  x : Integer;
  Background : TBitmap;
  Front : TBitmap;

implementation

{$R *.dfm} 

procedure TForm1.FormCreate(Sender: TObject);
begin
  Background := TBitmap.Create;
  Background.Width := 200;
  Background.Height := 200;
  Background.Canvas.Brush.Color := clgreen;
  Background.Canvas.FillRect(Classes.Rect(0,0,200,200));
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  inc(x);
  Front := TBitmap.Create;
  Front.Width := 200;
  Front.Height := 200;
  Front.Assign(Background);
  Front.Canvas.TextOut(1,1,IntToStr(x));

  BitBlt(Image1.Canvas.Handle,0,0,200,200,Front.Canvas.Handle,0,0,SRCCOPY);

  {nur als Test, ob logisch irgendwas falsch ist} 
  BitBlt(Canvas.Handle,0,0,200,200,Front.Canvas.Handle,0,0,SRCCOPY);


  Front.Free;
end;

end.