Chaotic fractals of mandelbrot

f(z) = z^2 + C

where z is a complex number (vector)

and C is a complex constant (vector of a constant norm)

output from my Xcode project:

for(i=0; i <iter;i++){

        float x = (z.x * z.x - z.y * z.y) + c.x;

        float y = 2.0 * (z.x * z.y) + c.y;

if((x * x + y * y) > 40.0) break; //distance from the origin>2 ==> done!!

        z.x = x;

        z.y = y;

}

After 355 iterations: