Step by step drawing of a curve

[epsilon]

Hallo everybody.
I have a TImage on my form and I want to draw a curve step by step - because of visualization. But if I use Repaint or Sleep(a time) after LineTo(x,y), it does nothing - the whole curve is designed immediately.

Thank's for help.

Epsilon

[marmin]

can you place more of your code?
you can also try a for-loop between the lineto , to fill any time.
if you do a repaint it paints everything that's on the canvas immediately.

[epsilon]

O.K. If I put a TImage on the TForm, the following code works fine:

Code: [Select]

procedure TForm1.Button4Click(Sender: TObject);
 var i: integer;
begin
With Image3 do
 begin
  DoubleBuffered:=True;
  Canvas.Brush.Color:=clWhite;
  Canvas.Pen.Color:=clRed;
  Canvas.Fillrect(Rect(0,0,width,height));
  Canvas.MoveTo(0, Height div 2);
  for i:=0 to 6283 do
  begin
   Canvas.LineTo(Round(i*width/6283), Round((Height div 2)*(1+SIN(i/1000))));
   if ((i mod 10)=0) then begin Application.ProcessMessages; Repaint; end;
  end;
 end;
end;
But, if I put the TImage on a TTabSheet of a TPageControl, the image blinks - there are gray strips. Try it and you will see.
Epsilon