Как быстро очистить канву
procedure TForm1.Button1Click(Sender: TObject);
begin
PatBlt(Form1.Canvas.Handle, 0, 0,
Form1.ClientWidth, Form1.ClientHeight, WHITENESS);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
PatBlt(Form1.Canvas.Handle, 0, 0,
Form1.ClientWidth, Form1.ClientHeight, WHITENESS);
end;