c++ creating animation help gdi and repaint window win32

[ramilol]

ok im trying to create a animation of circle i have a while loop that loops and set var value the varable will be used to set the circle x value
here is the loop

while(sd==1)
		{
			sf++;//globe var, sf equals 1
			onPaint(hdc);//paint the circle
			InvalidateRect (hWnd, NULL, TRUE);//it should repaint the window but it doesn't
			UpdateWindow(hWnd);
		}

well i can sucessfully draw the cirlce but not repaint it what happens is this it creates a circle with x value 1 than it creates another circle with value 3 it shouldn't it should delete the circle with value 2 than create new one with value 3
here is the draw circle code

VOID onPaint(HDC hdc)
{
   Graphics graphics(hdc);
   Pen      pen(Color(255, 0, 0, 255));
   graphics.DrawEllipse(&pen, sf , 0, 10, 10);
}

i posted this question in 2 different place still no answer would help me. i would really appreciation your help

[newb16]

You are right when you say "it should delete the circle with value 2". 'it' - is your program, the code of onPaint function. It should take care of erasing whatever garbage in the drawing context before it is called and draw what you need. It should not expect blank canvas.

[ramilol]

how am i suppose to do that?

[newb16]

I'd search for gdi function that contains 'fill' in its name.