How to draw a circle without use of floating point computation?

Question

Write a routine to draw a circle (x ** 2 + y ** 2 = r ** 2) without making use of any floating point computations at all ??

Answer 1

Use Mid Point Circle Algorithm

public static void DrawCircle(int x0, int y0, int radius)
{
  int x = radius, y = 0;
  int radiusError = 1-x;

  while(x >= y)
  {
    DrawPixel(x + x0, y + y0);
    DrawPixel(y + x0, x + y0);
    DrawPixel(-x + x0, y + y0);
    DrawPixel(-y + x0, x + y0);
    DrawPixel(-x + x0, -y + y0);
    DrawPixel(-y + x0, -x + y0);
    DrawPixel(x + x0, -y + y0);
    DrawPixel(y + x0, -x + y0);

    y++;
    if(radiusError<0)
            radiusError+=2*y+1;
    else
    {
            x--;
            radiusError+=2*(y-x+1);
    }
  }
}