Drawing A Line In MFC

Not sure what do you mean, dude.
Take a look at this example.
This way you can draw a circle using Polar based algorithm, HTH:

 void CircleDirect(HDC hdc,int xc,int yc, int R)
 {
   int x=0,y=R;
   int R2=R*R;
   Draw8Points(hdc,xc,yc,x,y);
        while(x<y)>
         {
       x++;
           y=round(sqrt((double)(R2-x*x)));
         Draw8Points(hdc,xc,yc,x,y);
        }
 }

 void Draw8Points(HDC hdc,int xc,int yc, int a, int b)
 {
          SetPixel(hdc, xc+a, yc+b, NULL);
          SetPixel(hdc, xc-a, yc+b, NULL);
          SetPixel(hdc, xc-a, yc-b, NULL);
          SetPixel(hdc, xc+a, yc-b, NULL);
          SetPixel(hdc, xc+b, yc+a, NULL);
          SetPixel(hdc, xc-b, yc+a, NULL);
          SetPixel(hdc, xc-b, yc-a, NULL);
          SetPixel(hdc, xc+b, yc-a, NULL);
}