mandelbulb

float mandelbulbDistance(Vec3 p)
{
    Vec3 v = p;
    Vec3 c = v;

    float r = 0.f;
    float d = 1.f;

    for(int n=0; n<=10; ++n)
    {
        r = v.length();
        if(r > 8.f) // Bailout
        {
            break;
        }

        float theta = acosf(v.z/r);
        float phi = atan2f(v.y, v.x);

        float rr = r * r;
        float rrrr = rr * rr;
        d = rrrr * rrrr * r * 10 * d + 1.f;
        float zr = rrrr * rrrr * rr;


        theta *= 10;
        phi *= 10;
        float sinTheta = sinf(theta);

        v = (Vec3(sinTheta*cosf(phi), sinf(phi)*sinTheta, cosf(theta))*zr) + c;
    }
    return (0.5f * r * logf(r)) / d;
}