public override double GenerateRayDifferential(CameraSample sample, ref RayDifferential rd)
{
++NumberOfRays;
Point pRas = new Point (sample.ImageX, sample.ImageY, 0.0);
Point pCam = new Point ();
RasterToCamera.Apply (pRas, ref pCam);
Vector dir = new Vector (pCam).Normalized;
rd = new RayDifferential (new Point (), dir, 0.0, double.PositiveInfinity);
if (LensRadius > 0.0)
{
double lensU = 0.0, lensV = 0.0;
MonteCarlo.ConcentricSampleDisk (sample.LensU, sample.LensV, ref lensU, ref lensV);
lensU *= LensRadius;
lensV *= LensRadius;
double ft = FocalDistance / rd.Direction.z;
Point pFocus = rd.Apply (ft);
rd.Origin = new Point (lensU, lensV, 0.0);
rd.Direction = (pFocus - rd.Origin).Normalized;
}
rd.RxOrigin = new Point (rd.Origin);
rd.RyOrigin = new Point (rd.Origin);
rd.RxDirection = (new Vector (pCam) + dxCamera).Normalized;
rd.RyDirection = (new Vector (pCam) + dyCamera).Normalized;
rd.Time = Util.Lerp (sample.Time, ShutterOpen, ShutterClose);
CameraToWorld.Apply (rd, ref rd);
rd.HasDifferentials = true;
return 1.0;
}
