/// <inheritdoc />
public override double GenerateRay(CameraSample sample, out Ray ray)
{
//ProfilePhase prof(Prof::GenerateCameraRay);
// Compute raster and camera sample positions
Point3D pFilm = new Point3D(sample.FilmPoint.X, sample.FilmPoint.Y, 0.0);
Point3D pCamera = RasterToCamera.AtPoint(pFilm);
ray = new Ray(new Point3D(0.0, 0.0, 0.0), pCamera.ToVector3D().Normalize());
// Modify ray for depth of field
if (LensRadius > 0.0)
{
// Sample point on lens
Point2D pLens = LensRadius * Sampling.ConcentricSampleDisk(sample.LensPoint);
// Compute point on plane of focus
double ft = FocalDistance / ray.Direction.Z;
Point3D pFocus = ray.AtPoint(ft);
// Update ray for effect of lens
ray.Origin = new Point3D(pLens.X, pLens.Y, 0.0);
ray.Direction = (pFocus - ray.Origin).ToVector3D().Normalize();
}
ray.Time = PbrtMath.Lerp(sample.Time, ShutterOpen, ShutterClose);
ray.Medium = Medium;
ray = CameraToWorld.ExecuteTransform(ray);
return(1.0);
}
/// <inheritdoc />
public PerspectiveCamera(AnimatedTransform cameraToWorld, Bounds2D screenWindow, double shutterOpen, double shutterClose, double lensr, double focald, double fov, Film film, Medium medium)
: base(cameraToWorld, Transform.Perspective(fov, 1e-2f, 1000.0), screenWindow, shutterOpen, shutterClose, lensr, focald, film, medium)
{
// Compute differential changes in origin for perspective camera rays
_dxCamera =
(RasterToCamera.AtPoint(new Point3D(1.0, 0.0, 0.0)) - RasterToCamera.AtPoint(new Point3D(0.0, 0.0, 0.0))).ToVector3D();
_dyCamera =
(RasterToCamera.AtPoint(new Point3D(0.0, 1.0, 0.0)) - RasterToCamera.AtPoint(new Point3D(0.0, 0.0, 0.0))).ToVector3D();
// Compute image plane bounds at $z=1$ for _PerspectiveCamera_
Point2I res = film.FullResolution;
Point3D MinPoint = RasterToCamera.AtPoint(new Point3D(0.0, 0.0, 0.0));
Point3D MaxPoint = RasterToCamera.AtPoint(new Point3D(res.X, res.Y, 0.0));
MinPoint /= MinPoint.Z;
MaxPoint /= MaxPoint.Z;
_a = Math.Abs((MaxPoint.X - MinPoint.X) * (MaxPoint.Y - MinPoint.Y));
}