public override Spectrum SampleL(Point p, float pEpsilon, LightSample ls,
float time, out Vector wi, out float pdf,
out VisibilityTester vis)
{
wi = _direction;
pdf = 1.0f;
vis = new VisibilityTester(p, pEpsilon, wi, time);
return _radiance;
}
public override Spectrum SampleL(Scene scene, LightSample ls, float u1, float u2, float time, out Ray ray, out Normal ns, out float pdf)
{
ray = new Ray(_lightPosition,
MonteCarloUtilities.UniformSampleSphere(ls.UPos0, ls.UPos1),
0.0f, float.PositiveInfinity, time);
ns = (Normal) ray.Direction;
pdf = MonteCarloUtilities.UniformSpherePdf();
return _intensity;
}
public override Spectrum SampleL(
Point p, float pEpsilon, LightSample ls, float time, out Vector wi,
out float pdf, out VisibilityTester vis)
{
wi = Vector.Normalize(_lightPosition - p);
pdf = 1.0f;
vis = new VisibilityTester(p, pEpsilon, _lightPosition, 0.0f, time);
return _intensity / Point.DistanceSquared(_lightPosition, p);
}
public override Spectrum SampleL(Scene scene, LightSample ls, float u1, float u2, float time, out Ray ray, out Normal ns, out float pdf)
{
// Choose point on disk oriented toward infinite light direction
Point worldCenter;
float worldRadius;
scene.WorldBound.BoundingSphere(out worldCenter, out worldRadius);
Vector v1, v2;
Vector.CoordinateSystem(_direction, out v1, out v2);
float d1, d2;
MonteCarloUtilities.ConcentricSampleDisk(ls.UPos0, ls.UPos1, out d1, out d2);
Point Pdisk = worldCenter + worldRadius * (d1 * v1 + d2 * v2);
// Set ray origin and direction for infinite light ray
ray = new Ray(Pdisk + worldRadius * _direction, -_direction, 0.0f, float.PositiveInfinity, time);
ns = (Normal) ray.Direction;
pdf = 1.0f / (MathUtility.Pi * worldRadius * worldRadius);
return _radiance;
}
public override Spectrum SampleL(Scene scene, LightSample ls, float u1, float u2, float time, out Ray ray, out Normal ns, out float pdf)
{
throw new System.NotImplementedException();
}
public override Spectrum SampleL(Point p, float pEpsilon, LightSample ls, float time, out Vector wi, out float pdf,
out VisibilityTester vis)
{
throw new System.NotImplementedException();
}
public abstract Spectrum SampleL(Scene scene, LightSample ls, float u1, float u2,
float time, out Ray ray, out Normal ns, out float pdf);
public abstract Spectrum SampleL(Point p, float pEpsilon, LightSample ls,
float time, out Vector wi, out float pdf, out VisibilityTester vis);
