Depth of Field

// from PerspectiveCamera.hxx

virtual bool InitRayDOF(double x, double y, Ray &ray, double focusDistance, double circleOfConfusionSize)

{

       InitRay(x, y, ray);

       Vec3f focusedPoint = ray.org + focusDistance * ray.dir;

       // Move origin of camera ray on one random point on circle with radius of circleOfConfusionSize

       double fi = 2*M_PI*frand();

       Vec3f newOrigin = ray.org + cos(fi)*circleOfConfusionSize * xAxis + sin(fi) * circleOfConfusionSize * yAxis;

       ray.dir = focusedPoint - newOrigin;

       Normalize(ray.dir);

       ray.org = newOrigin;

       return true;

};