public override Spectrum Power(Scene scene)
{
Point worldCenter;
double worldRadius;
scene.WorldBound.BoundingSphere (out worldCenter, out worldRadius);
return L * Util.Pi * worldRadius * worldRadius;
}
public static Spectrum SpecularReflect(RayDifferential ray, BSDF bsdf, Intersection isect, IRenderer renderer, Scene scene, Sample sample)
{
Vector wo = -ray.Direction, wi = new Vector ();
double pdf = 0.0;
Point p = bsdf.dgShading.p;
Normal n = bsdf.dgShading.n;
Spectrum f = bsdf.SampleF (wo, ref wi, new BSDFSample (), ref pdf, BxDFType.BSDF_REFLECTION | BxDFType.BSDF_SPECULAR);
Spectrum L = new Spectrum ();
if (pdf > 0.0 && !f.IsBlack && Util.AbsDot (wi, n) != 0.0)
{
RayDifferential rd = new RayDifferential (p, wi, ray, isect.RayEpsilon);
if (ray.HasDifferentials)
{
rd.HasDifferentials = true;
rd.RxOrigin = p + isect.dg.dpdx;
rd.RyOrigin = p + isect.dg.dpdy;
Normal dndx = bsdf.dgShading.dndu * bsdf.dgShading.dudx + bsdf.dgShading.dndv * bsdf.dgShading.dvdx;
Normal dndy = bsdf.dgShading.dndu * bsdf.dgShading.dudy + bsdf.dgShading.dndv * bsdf.dgShading.dvdy;
Vector dwodx = -ray.RxDirection - wo, dwody = -ray.Direction - wo;
double dDNdx = (dwodx ^ n) + (wo ^ dndx);
double dDNdy = (dwody ^ n) + (wo ^ dndy);
rd.RxDirection = wi - dwodx + 2 * new Vector ((wo ^ n) * dndx + dDNdx * n);
rd.RyDirection = wi - dwody + 2 * new Vector ((wo ^ n) * dndy + dDNdy * n);
}
Spectrum Li = renderer.Li (scene, rd, sample);
L = f * Li * Util.AbsDot (wi, n) / pdf;
}
return L;
}
public SamplerRendererTask(Scene scene, IRenderer renderer, ICamera camera, ProgressReporter reporter, ISampler sampler, Sample sample, int tn, int tc)
{
Scene = scene;
Camera = camera;
Renderer = renderer;
MainSampler = sampler;
OrigSample = sample;
TaskNumber = tn;
TaskCount = tc;
Reporter = reporter;
}
public override Spectrum SampleL(Scene scene, LightSample ls, double u1, double u2, double time, ref Ray ray, ref Normal Ns, ref double pdf)
{
Point org = ShapeSet.Sample (ls, ref Ns);
Vector dir = MonteCarlo.UniformSampleSphere (u1, u2);
if ((dir ^ Ns) < 0.0)
dir *= -1.0;
ray = new Ray (org, dir, 0.001, double.PositiveInfinity, time);
pdf = ShapeSet.Pdf (org) * Util.InvTwoPi;
Spectrum Ls = L (org, Ns, dir);
return Ls;
}
public override Spectrum SampleL(Scene scene, LightSample ls, double u1, double u2, double time, ref Ray ray, ref Normal Ns, ref double pdf)
{
// Choose point on disk oriented toward infinite light direction
Point worldCenter;
double worldRadius;
scene.WorldBound.BoundingSphere (out worldCenter, out worldRadius);
Vector v1, v2;
Util.CoordinateSystem (LightDir, out v1, out v2);
double d1 = 0.0, d2 = 0.0;
MonteCarlo.ConcentricSampleDisk (ls.uPos[0], ls.uPos[1], ref d1, ref d2);
Point Pdisk = worldCenter + worldRadius * (d1 * v1 + d2 * v2);
// Set ray origin and direction for infinite light ray
ray = new Ray (Pdisk + worldRadius * LightDir, -LightDir, 0.0, double.PositiveInfinity, time);
Ns = new Normal (ray.Direction);
pdf = 1.0 / (Util.Pi * worldRadius * worldRadius);
return L;
}
public static Spectrum SpecularTransmit(RayDifferential ray, BSDF bsdf, Intersection isect, IRenderer renderer, Scene scene, Sample sample)
{
Vector wo = -ray.Direction, wi = new Vector ();
double pdf = 0.0;
Point p = bsdf.dgShading.p;
Normal n = bsdf.dgShading.n;
Spectrum f = bsdf.SampleF (wo, ref wi, new BSDFSample (), ref pdf, BxDFType.BSDF_TRANSMISSION | BxDFType.BSDF_SPECULAR);
Spectrum L = new Spectrum ();
if (pdf > 0.0 && !f.IsBlack && Util.AbsDot (wi, n) != 0.0)
{
RayDifferential rd = new RayDifferential (p, wi, ray, isect.RayEpsilon);
if (ray.HasDifferentials)
{
rd.HasDifferentials = true;
rd.RxOrigin = p + isect.dg.dpdx;
rd.RyOrigin = p + isect.dg.dpdy;
double eta = bsdf.Eta;
Vector w = -wo;
if ((wo ^ n) < 0.0)
eta = 1.0 / eta;
Normal dndx = bsdf.dgShading.dndu * bsdf.dgShading.dudx + bsdf.dgShading.dndv * bsdf.dgShading.dvdx;
Normal dndy = bsdf.dgShading.dndu * bsdf.dgShading.dudy + bsdf.dgShading.dndv * bsdf.dgShading.dvdy;
Vector dwodx = -ray.RxDirection - wo, dwody = -ray.RyDirection - wo;
double dDNdx = (dwodx ^ n) + (wo ^ dndx);
double dDNdy = (dwody ^ n) + (wo ^ dndy);
double mu = eta * (w ^ n) - (wi ^ n);
double dmudx = (eta - (eta * eta * (w ^ n)) / (wi ^ n)) * dDNdx;
double dmudy = (eta - (eta * eta * (w ^ n)) / (wi ^ n)) * dDNdy;
rd.RxDirection = wi + eta * dwodx - new Vector (mu * dndx + dmudx * n);
rd.RyDirection = wi + eta * dwody - new Vector (mu * dndy + dmudy * n);
}
Spectrum Li = renderer.Li (scene, rd, sample);
L = f * Li * Util.AbsDot (wi, n) / pdf;
}
return L;
}
public override Spectrum Transmittance(Scene scene, IRenderer renderer, RayDifferential ray, Sample sample)
{
if (scene.VolumeRegion == null)
return new Spectrum (1.0);
double step, offset;
if (sample != null)
{
step = StepSize;
offset = sample.samples[sample.oneD + TauSampleOffset][0];
}
else
{
step = 4.0 * StepSize;
offset = Util.Random.NextDouble ();
}
/*Spectrum tau = scene.VolumeRegion.Tau (ray, step, offset);
return (-tau).Exp;*/
return null;
}
public override Spectrum Power(Scene scene)
{
return Lemit * area * Util.Pi;
}
public override void RequestSamples(ISampler sampler, Sample sample, Scene scene)
{
TauSampleOffset = sample.Add1D (1);
ScatterSampleOffset = sample.Add1D (1);
}
public override Spectrum Li(Scene scene, IRenderer renderer, RayDifferential ray, Sample sample, ref Spectrum transmittance)
{
transmittance = new Spectrum (1.0);
return new Spectrum ();
}