unit P_form;
interface
uses
SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
Forms, Dialogs, ExtCtrls;
type
TForm1 = class(TForm)
Image1: TImage;
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
FClientInstance,
FPrevClientProc : TFarProc;
procedure ClientWndProc(VAR Message: TMessage);
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
procedure TForm1.ClientWndProc(VAR Message: TMessage);
var
MyDC : hDC;
Ro, Co : Word;
begin
with Messagedo
case Msg of
WM_ERASEBKGND:
begin
MyDC := TWMEraseBkGnd(Message).DC;
for Ro := 0 TO ClientHeight DIV Image1.Picture.Heightdo
for Co := 0 TO ClientWIDTH DIV Image1.Picture.Widthdo
BitBlt(MyDC, Co*Image1.Picture.Width, Ro*Image1.Picture.Height,
Image1.Picture.Width, Image1.Picture.Height,
Image1.Picture.Bitmap.Canvas.Handle, 0, 0, SRCCOPY);
Result := 1;
end;
else
Result := CallWindowProc(FPrevClientProc, ClientHandle, Msg, wParam, lParam);
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
FClientInstance := MakeObjectInstance(ClientWndProc);
FPrevClientProc := Pointer(GetWindowLong(ClientHandle, GWL_WNDPROC));
SetWindowLong(ClientHandle, GWL_WNDPROC, LongInt(FClientInstance));
end;
end.