Color3f Li(const Scene *scene, Sampler *sampler, const Ray3f &ray) const {
/* Find the surface that is visible in the requested direction */
Intersection its;
//check if the ray intersects the scene
if (!scene->rayIntersect(ray, its)) {
//check if a distant disk light is set
const Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk == nullptr ) return Color3f(0.0f);
//sample the distant disk light
return distantsDisk->sampleL(ray.d);
}
//get the radiance of hitten object
Color3f Le(0.0f, 0.0f, 0.0f);
if (its.mesh->isEmitter() ) {
const Emitter* areaLightEM = its.mesh->getEmitter();
const areaLight* aEM = static_cast<const areaLight *> (areaLightEM);
Le = aEM->sampleL(-ray.d, its.shFrame.n, its);
}
//get the asigned BSDF
const BSDF* curBSDF = its.mesh->getBSDF();
Color3f Ld(0.0f, 0.0f, 0.0f);
Color3f f(0.0f, 0.0f, 0.0f);
Color3f totalLight(0.0f, 0.0f, 0.0f);
//transform to the local frame
//create a BRDF Query
BSDFQueryRecord query = BSDFQueryRecord(its.toLocal(-ray.d), Vector3f(0.0f), EMeasure::ESolidAngle);
//sample the BRDF
Color3f mats = curBSDF->sample(query, sampler->next2D());
if(mats.maxCoeff() > 0.0f) {
//Check for the light source
Vector3f wo = its.toWorld(query.wo);
Ray3f shadowRay(its.p, wo);
Intersection itsShadow;
if (scene->rayIntersect(shadowRay, itsShadow)) {
//intersection check if mesh is emitter
if(itsShadow.mesh->isEmitter()){
Ld = itsShadow.mesh->getEmitter()->radiance();
}
} else {
//check for distant disk light
const Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk != nullptr ) Ld = distantsDisk->sampleL(wo);
}
totalLight += Ld * mats;
}
return Le + totalLight;
}
Color3f Li(const Scene *scene, Sampler *sampler, const Ray3f &ray) const {
/* Find the surface that is visible in the requested direction */
Intersection its;
//check if the ray intersects the scene
if (!scene->rayIntersect(ray, its)) {
//check if a distant disk light is set
const Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk == nullptr ) return Color3f(0.0f);
//sample the distant disk light
Vector3f d = ray.d;
return distantsDisk->sampleL(d);
}
//get the Number of lights from the scene
const std::vector<Emitter *> lights = scene->getEmitters();
uint32_t nLights = lights.size();
Color3f tp(1.0f, 1.0f, 1.0f);
Color3f L(0.0f, 0.0f, 0.0f);
Ray3f pathRay(ray.o, ray.d);
bool deltaFlag = true;
while(true) {
if (its.mesh->isEmitter() && deltaFlag) {
const Emitter* areaLightEM = its.mesh->getEmitter();
const areaLight* aEM = static_cast<const areaLight *> (areaLightEM);
L += tp * aEM->sampleL(-pathRay.d, its.shFrame.n, its);
}
//Light sampling
//randomly select a lightsource
uint32_t var = uint32_t(std::min(sampler->next1D()*nLights, float(nLights) - 1.0f));
//init the light color
Color3f Li(0.0f, 0.0f, 0.0f);
Color3f Ld(1.0f, 1.0f, 1.0f);
//create a sample for the light
const BSDF* curBSDF = its.mesh->getBSDF();
const Point2f lightSample = sampler->next2D();
VisibilityTester vis;
Vector3f wo;
float lightpdf;
float bsdfpdf;
Normal3f n = its.shFrame.n;
deltaFlag = curBSDF->isDeltaBSDF();
//sample the light
{
Li = lights[var]->sampleL(its.p, Epsilon, lightSample , &wo, &lightpdf, &vis);
lightpdf /= float(nLights);
//check if the pdf of the sample is greater than 0 and if the color is not black
if(lightpdf > 0 && Li.maxCoeff() != 0.0f) {
//calculate the cosine term wi in my case the vector to the light
float cosTerm = std::abs(n.dot(wo));
const BSDFQueryRecord queryEM = BSDFQueryRecord(its.toLocal(- pathRay.d), its.toLocal(wo), EMeasure::ESolidAngle, sampler);
Color3f f = curBSDF->eval(queryEM);
if(f.maxCoeff() > 0.0f && f.minCoeff() >= 0.0f && vis.Unoccluded(scene)) {
bsdfpdf = curBSDF->pdf(queryEM);
float weight = BalanceHeuristic(float(1), lightpdf, float(1), bsdfpdf);
if(curBSDF->isDeltaBSDF()) weight = 1.0f;
if(bsdfpdf > 0.0f) {
Ld = (weight * f * Li * cosTerm) / lightpdf;
L += tp * Ld;
} else {
//cout << "bsdfpdf = " << bsdfpdf << endl;
//cout << "f = " << f << endl;
}
}
}
}
//Material part
BSDFQueryRecord queryMats = BSDFQueryRecord(its.toLocal(-pathRay.d), Vector3f(0.0f), EMeasure::ESolidAngle, sampler);
Color3f fi = curBSDF->sample(queryMats, sampler->next2D());
bsdfpdf = curBSDF->pdf(queryMats);
lightpdf = 0.0f;
if(fi.maxCoeff() > 0.0f && fi.minCoeff() >= 0.0f) {
if(bsdfpdf > 0.0f) {
Ray3f shadowRay(its.p, its.toWorld(queryMats.wo));
Intersection lightIsect;
if (scene->rayIntersect(shadowRay, lightIsect)) {
if(lightIsect.mesh->isEmitter()){
const Emitter* areaLightEMcur = lightIsect.mesh->getEmitter();
const areaLight* aEMcur = static_cast<const areaLight *> (areaLightEMcur);
Li = aEMcur->sampleL(-shadowRay.d, lightIsect.shFrame.n, lightIsect);
lightpdf = aEMcur->pdf(its.p, (lightIsect.p - its.p).normalized(), lightIsect.p, Normal3f(lightIsect.shFrame.n));
}
} else {
const Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk != nullptr ) {
//check if THIS is right!
Li = distantsDisk->sampleL(lightIsect.toWorld(queryMats.wo));
lightpdf = distantsDisk->pdf(Point3f(0.0f), wo, Point3f(0.0f), Normal3f(0.0f));
}
}
lightpdf /= float(nLights);
//calculate the weights
float weight = BalanceHeuristic(float(1), bsdfpdf, float(1), lightpdf);
//check if the lightcolor is not black
if(Li.maxCoeff() > 0.0f && lightpdf > 0.0f ) {
//wo in my case the vector to the light
Ld = weight * Li * fi;
L += tp * Ld;
}
}
tp *= fi;
} else {
break;
}
wo = its.toWorld(queryMats.wo);
pathRay = Ray3f(its.p, wo);
if (!scene->rayIntersect(pathRay, its)) {
const Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk != nullptr ) {
//sample the distant disk light
Vector3f d = pathRay.d;
L += tp * distantsDisk->sampleL(d);
}
break;
}
float maxCoeff = tp.maxCoeff();
float q = std::min(0.99f, maxCoeff);
if(q < sampler->next1D()){
break;
}
tp /= q;
}
return L;
}
void PreviewWorker::processCoherent(const WorkUnit *workUnit, WorkResult *workResult,
const bool &stop) {
#if defined(MTS_HAS_COHERENT_RT)
const RectangularWorkUnit *rect = static_cast<const RectangularWorkUnit *>(workUnit);
ImageBlock *block = static_cast<ImageBlock *>(workResult);
block->setOffset(rect->getOffset());
block->setSize(rect->getSize());
/* Some constants */
const int sx = rect->getOffset().x, sy = block->getOffset().y;
const int ex = sx + rect->getSize().x, ey = sy + rect->getSize().y;
const int width = rect->getSize().x;
const SSEVector MM_ALIGN16 xOffset(0.0f, 1.0f, 0.0f, 1.0f);
const SSEVector MM_ALIGN16 yOffset(0.0f, 0.0f, 1.0f, 1.0f);
const int pixelOffset[] = {0, 1, width, width+1};
const __m128 clamping = _mm_set1_ps(1/(m_minDist*m_minDist));
uint8_t temp[MTS_KD_INTERSECTION_TEMP*4];
const __m128 camTL[3] = {
_mm_set1_ps(m_cameraTL.x),
_mm_set1_ps(m_cameraTL.y),
_mm_set1_ps(m_cameraTL.z)
};
const __m128 camDx[3] = {
_mm_set1_ps(m_cameraDx.x),
_mm_set1_ps(m_cameraDx.y),
_mm_set1_ps(m_cameraDx.z)
};
const __m128 camDy[3] = {
_mm_set1_ps(m_cameraDy.x),
_mm_set1_ps(m_cameraDy.y),
_mm_set1_ps(m_cameraDy.z)
};
const __m128 lumPos[3] = {
_mm_set1_ps(m_vpl.its.p.x),
_mm_set1_ps(m_vpl.its.p.y),
_mm_set1_ps(m_vpl.its.p.z)
};
const __m128 lumDir[3] = {
_mm_set1_ps(m_vpl.its.shFrame.n.x),
_mm_set1_ps(m_vpl.its.shFrame.n.y),
_mm_set1_ps(m_vpl.its.shFrame.n.z)
};
/* Some local variables */
int pos = 0;
int numRays = 0;
RayPacket4 MM_ALIGN16 primRay4, secRay4;
Intersection4 MM_ALIGN16 its4, secIts4;
RayInterval4 MM_ALIGN16 itv4, secItv4;
SSEVector MM_ALIGN16 nSecD[3], cosThetaLight, invLengthSquared;
Spectrum emitted[4], direct[4];
Intersection its;
Vector wo, wi;
its.hasUVPartials = false;
bool diffuseVPL = false, vplOnSurface = false;
Spectrum vplWeight;
if (m_vpl.type == ESurfaceVPL && (m_diffuseSources || m_vpl.its.shape->getBSDF()->getType() == BSDF::EDiffuseReflection)) {
diffuseVPL = true;
vplOnSurface = true;
vplWeight = m_vpl.its.shape->getBSDF()->getDiffuseReflectance(m_vpl.its) * m_vpl.P / M_PI;
} else if (m_vpl.type == ELuminaireVPL) {
vplOnSurface = m_vpl.luminaire->getType() & Luminaire::EOnSurface;
diffuseVPL = m_vpl.luminaire->getType() & Luminaire::EDiffuseDirection;
EmissionRecord eRec(m_vpl.luminaire,
ShapeSamplingRecord(m_vpl.its.p, m_vpl.its.shFrame.n), m_vpl.its.shFrame.n);
vplWeight = m_vpl.P * m_vpl.luminaire->evalDirection(eRec);
}
primRay4.o[0].ps = _mm_set1_ps(m_cameraO.x);
primRay4.o[1].ps = _mm_set1_ps(m_cameraO.y);
primRay4.o[2].ps = _mm_set1_ps(m_cameraO.z);
secItv4.mint.ps = _mm_set1_ps(ShadowEpsilon);
/* Work on 2x2 sub-blocks */
for (int y=sy; y<ey; y += 2, pos += width) {
for (int x=sx; x<ex; x += 2, pos += 2) {
/* Generate camera rays without normalization */
const __m128
xPixel = _mm_add_ps(xOffset.ps, _mm_set1_ps((float) x)),
yPixel = _mm_add_ps(yOffset.ps, _mm_set1_ps((float) y));
primRay4.d[0].ps = _mm_add_ps(camTL[0], _mm_add_ps(
_mm_mul_ps(xPixel, camDx[0]), _mm_mul_ps(yPixel, camDy[0])));
primRay4.d[1].ps = _mm_add_ps(camTL[1], _mm_add_ps(
_mm_mul_ps(xPixel, camDx[1]), _mm_mul_ps(yPixel, camDy[1])));
primRay4.d[2].ps = _mm_add_ps(camTL[2], _mm_add_ps(
_mm_mul_ps(xPixel, camDx[2]), _mm_mul_ps(yPixel, camDy[2])));
primRay4.dRcp[0].ps = _mm_div_ps(SSEConstants::one.ps, primRay4.d[0].ps);
primRay4.dRcp[1].ps = _mm_div_ps(SSEConstants::one.ps, primRay4.d[1].ps);
primRay4.dRcp[2].ps = _mm_div_ps(SSEConstants::one.ps, primRay4.d[2].ps);
/* Ray coherence test */
const int primSignsX = _mm_movemask_ps(primRay4.d[0].ps);
const int primSignsY = _mm_movemask_ps(primRay4.d[1].ps);
const int primSignsZ = _mm_movemask_ps(primRay4.d[2].ps);
const bool primCoherent =
(primSignsX == 0 || primSignsX == 0xF)
&& (primSignsY == 0 || primSignsY == 0xF)
&& (primSignsZ == 0 || primSignsZ == 0xF);
/* Trace the primary rays */
its4.t = SSEConstants::p_inf;
if (EXPECT_TAKEN(primCoherent)) {
primRay4.signs[0][0] = primSignsX ? 1 : 0;
primRay4.signs[1][0] = primSignsY ? 1 : 0;
primRay4.signs[2][0] = primSignsZ ? 1 : 0;
m_kdtree->rayIntersectPacket(primRay4, itv4, its4, temp);
} else {
m_kdtree->rayIntersectPacketIncoherent(primRay4, itv4, its4, temp);
}
numRays += 4;
/* Generate secondary rays */
secRay4.o[0].ps = _mm_add_ps(primRay4.o[0].ps, _mm_mul_ps(its4.t.ps, primRay4.d[0].ps));
secRay4.o[1].ps = _mm_add_ps(primRay4.o[1].ps, _mm_mul_ps(its4.t.ps, primRay4.d[1].ps));
secRay4.o[2].ps = _mm_add_ps(primRay4.o[2].ps, _mm_mul_ps(its4.t.ps, primRay4.d[2].ps));
secRay4.d[0].ps = _mm_sub_ps(lumPos[0], secRay4.o[0].ps);
secRay4.d[1].ps = _mm_sub_ps(lumPos[1], secRay4.o[1].ps);
secRay4.d[2].ps = _mm_sub_ps(lumPos[2], secRay4.o[2].ps);
/* Normalization */
const __m128
lengthSquared = _mm_add_ps(_mm_add_ps(
_mm_mul_ps(secRay4.d[0].ps, secRay4.d[0].ps),
_mm_mul_ps(secRay4.d[1].ps, secRay4.d[1].ps)),
_mm_mul_ps(secRay4.d[2].ps, secRay4.d[2].ps)),
invLength = _mm_rsqrt_ps(lengthSquared);
invLengthSquared.ps = _mm_min_ps(_mm_rcp_ps(lengthSquared), clamping);
nSecD[0].ps = _mm_mul_ps(secRay4.d[0].ps, invLength);
nSecD[1].ps = _mm_mul_ps(secRay4.d[1].ps, invLength);
nSecD[2].ps = _mm_mul_ps(secRay4.d[2].ps, invLength);
secRay4.dRcp[0].ps = _mm_div_ps(SSEConstants::one.ps, secRay4.d[0].ps);
secRay4.dRcp[1].ps = _mm_div_ps(SSEConstants::one.ps, secRay4.d[1].ps);
secRay4.dRcp[2].ps = _mm_div_ps(SSEConstants::one.ps, secRay4.d[2].ps);
cosThetaLight.ps = _mm_sub_ps(_mm_setzero_ps(),
_mm_add_ps(_mm_add_ps(
_mm_mul_ps(nSecD[0].ps, lumDir[0]),
_mm_mul_ps(nSecD[1].ps, lumDir[1])),
_mm_mul_ps(nSecD[2].ps, lumDir[2])));
secItv4.maxt.ps = _mm_set1_ps(1-ShadowEpsilon);
/* Shading (scalar) --- this is way too much work and should be
rewritten to be smarter in special cases */
for (int idx=0; idx<4; ++idx) {
if (EXPECT_NOT_TAKEN(its4.t.f[idx] == std::numeric_limits<float>::infinity())) {
/* Don't trace a secondary ray */
secItv4.maxt.f[idx] = 0;
emitted[idx] = m_scene->LeBackground(Ray(
Point(primRay4.o[0].f[idx], primRay4.o[1].f[idx], primRay4.o[2].f[idx]),
Vector(primRay4.d[0].f[idx], primRay4.d[1].f[idx], primRay4.d[2].f[idx]),
0.0f
)) * m_backgroundScale;
memset(&direct[idx], 0, sizeof(Spectrum));
continue;
}
const unsigned int primIndex = its4.primIndex.i[idx];
const Shape *shape = (*m_shapes)[its4.shapeIndex.i[idx]];
const BSDF *bsdf = shape->getBSDF();
if (EXPECT_NOT_TAKEN(!bsdf)) {
memset(&emitted[idx], 0, sizeof(Spectrum));
memset(&direct[idx], 0, sizeof(Spectrum));
continue;
}
if (EXPECT_TAKEN(primIndex != KNoTriangleFlag)) {
const TriMesh *mesh = static_cast<const TriMesh *>(shape);
const Triangle &t = mesh->getTriangles()[primIndex];
const Normal *normals = mesh->getVertexNormals();
const Point2 *texcoords = mesh->getVertexTexcoords();
const Spectrum *colors = mesh->getVertexColors();
const TangentSpace * tangents = mesh->getVertexTangents();
const Float beta = its4.u.f[idx],
gamma = its4.v.f[idx],
alpha = 1.0f - beta - gamma;
const uint32_t idx0 = t.idx[0], idx1 = t.idx[1], idx2 = t.idx[2];
if (EXPECT_TAKEN(normals)) {
const Normal &n0 = normals[idx0],
&n1 = normals[idx1],
&n2 = normals[idx2];
its.shFrame.n = normalize(n0 * alpha + n1 * beta + n2 * gamma);
} else {
const Point *positions = mesh->getVertexPositions();
const Point &p0 = positions[idx0],
&p1 = positions[idx1],
&p2 = positions[idx2];
Vector sideA = p1 - p0, sideB = p2 - p0;
Vector n = cross(sideA, sideB);
Float nLengthSqr = n.lengthSquared();
if (nLengthSqr != 0)
n /= std::sqrt(nLengthSqr);
its.shFrame.n = Normal(n);
}
if (EXPECT_TAKEN(texcoords)) {
const Point2 &t0 = texcoords[idx0],
&t1 = texcoords[idx1],
&t2 = texcoords[idx2];
its.uv = t0 * alpha + t1 * beta + t2 * gamma;
} else {
its.uv = Point2(0.0f);
}
if (EXPECT_NOT_TAKEN(colors)) {
const Spectrum &c0 = colors[idx0],
&c1 = colors[idx1],
&c2 = colors[idx2];
its.color = c0 * alpha + c1 * beta + c2 * gamma;
}
if (EXPECT_NOT_TAKEN(tangents)) {
const TangentSpace &t0 = tangents[idx0],
&t1 = tangents[idx1],
&t2 = tangents[idx2];
its.dpdu = t0.dpdu * alpha + t1.dpdu * beta + t2.dpdu * gamma;
its.dpdv = t0.dpdv * alpha + t1.dpdv * beta + t2.dpdv * gamma;
}
} else {
Ray ray(
Point(primRay4.o[0].f[idx], primRay4.o[1].f[idx], primRay4.o[2].f[idx]),
Vector(primRay4.d[0].f[idx], primRay4.d[1].f[idx], primRay4.d[2].f[idx]),
0.0f
);
its.t = its4.t.f[idx];
shape->fillIntersectionRecord(ray, temp + idx * MTS_KD_INTERSECTION_TEMP + 8, its);
bsdf = its.shape->getBSDF();
}
wo.x = nSecD[0].f[idx]; wo.y = nSecD[1].f[idx]; wo.z = nSecD[2].f[idx];
if (EXPECT_TAKEN(!shape->isLuminaire())) {
memset(&emitted[idx], 0, sizeof(Spectrum));
} else {
Vector d(-primRay4.d[0].f[idx], -primRay4.d[1].f[idx], -primRay4.d[2].f[idx]);
emitted[idx] = shape->getLuminaire()->Le(ShapeSamplingRecord(its.p, its.shFrame.n), d);
}
if (EXPECT_TAKEN(bsdf->getType() == BSDF::EDiffuseReflection && diffuseVPL)) {
/* Fast path */
direct[idx] = (bsdf->getDiffuseReflectance(its) * vplWeight)
* (std::max((Float) 0.0f, dot(wo, its.shFrame.n))
* (vplOnSurface ? (std::max(cosThetaLight.f[idx], (Float) 0.0f) * INV_PI) : INV_PI)
* invLengthSquared.f[idx]);
} else {
wi.x = -primRay4.d[0].f[idx];
wi.y = -primRay4.d[1].f[idx];
wi.z = -primRay4.d[2].f[idx];
its.p.x = secRay4.o[0].f[idx];
its.p.y = secRay4.o[1].f[idx];
its.p.z = secRay4.o[2].f[idx];
if (EXPECT_NOT_TAKEN(bsdf->getType() & BSDF::EAnisotropic)) {
its.shFrame.s = normalize(its.dpdu - its.shFrame.n
* dot(its.shFrame.n, its.dpdu));
its.shFrame.t = cross(its.shFrame.n, its.shFrame.s);
} else {
coordinateSystem(its.shFrame.n, its.shFrame.s, its.shFrame.t);
}
const Float ctLight = cosThetaLight.f[idx];
wi = normalize(wi);
its.wi = its.toLocal(wi);
wo = its.toLocal(wo);
if (!diffuseVPL) {
if (m_vpl.type == ESurfaceVPL) {
BSDFQueryRecord bRec(m_vpl.its, m_vpl.its.toLocal(wi));
bRec.quantity = EImportance;
vplWeight = m_vpl.its.shape->getBSDF()->eval(bRec) * m_vpl.P;
} else {
EmissionRecord eRec(m_vpl.luminaire,
ShapeSamplingRecord(m_vpl.its.p, m_vpl.its.shFrame.n), wi);
eRec.type = EmissionRecord::EPreview;
vplWeight = m_vpl.luminaire->evalDirection(eRec) * m_vpl.P;
}
}
if (EXPECT_TAKEN(ctLight >= 0)) {
direct[idx] = (bsdf->eval(BSDFQueryRecord(its, wo)) * vplWeight
* ((vplOnSurface ? std::max(ctLight, (Float) 0.0f) : 1.0f) * invLengthSquared.f[idx]));
} else {
memset(&direct[idx], 0, sizeof(Spectrum));
}
}
++numRays;
}
/* Shoot the secondary rays */
const int secSignsX = _mm_movemask_ps(secRay4.d[0].ps);
const int secSignsY = _mm_movemask_ps(secRay4.d[1].ps);
const int secSignsZ = _mm_movemask_ps(secRay4.d[2].ps);
const bool secCoherent =
(secSignsX == 0 || secSignsX == 0xF)
&& (secSignsY == 0 || secSignsY == 0xF)
&& (secSignsZ == 0 || secSignsZ == 0xF);
/* Shoot the secondary rays */
secIts4.t = SSEConstants::p_inf;
if (EXPECT_TAKEN(secCoherent)) {
secRay4.signs[0][0] = secSignsX ? 1 : 0;
secRay4.signs[1][0] = secSignsY ? 1 : 0;
secRay4.signs[2][0] = secSignsZ ? 1 : 0;
m_kdtree->rayIntersectPacket(secRay4, secItv4, secIts4, temp);
} else {
m_kdtree->rayIntersectPacketIncoherent(secRay4, secItv4, secIts4, temp);
}
for (int idx=0; idx<4; ++idx) {
if (EXPECT_TAKEN(secIts4.t.f[idx] == std::numeric_limits<float>::infinity()))
block->setPixel(pos+pixelOffset[idx], direct[idx]+emitted[idx]);
else
block->setPixel(pos+pixelOffset[idx], emitted[idx]);
}
}
}
block->setExtra(numRays);
#else
Log(EError, "Coherent raytracing support was not compiled into this binary!");
#endif
}
void preprocess(const Scene *scene) {
/* Create a sample generator for the preprocess step */
Sampler *sampler = static_cast<Sampler *>(
NoriObjectFactory::createInstance("independent", PropertyList()));
Emitter* distantsDisk = scene->getDistantEmitter();
if(distantsDisk != nullptr ) {
float lngstDir = scene->getBoundingBox().getLongestDirection();
distantsDisk->setMaxRadius(lngstDir);
}
/* Allocate memory for the photon map */
m_photonMap = std::unique_ptr<PhotonMap>(new PhotonMap());
m_photonMap->reserve(m_photonCount);
/* Estimate a default photon radius */
if (m_photonRadius == 0)
m_photonRadius = scene->getBoundingBox().getExtents().norm() / 500.0f;
int storedPhotons = 0;
const std::vector<Emitter *> lights = scene->getEmitters();
int nLights = lights.size();
Color3f tp(1.0f, 1.0f, 1.0f);
cout << "Starting to create "<< m_photonCount << " photons!" << endl;
int percentDone= 0;
int onePercent = int(floor(m_photonCount / 100.0));
// create the expected number of photons
while(storedPhotons < m_photonCount) {
//uniformly sample 1 light (assuming that we only have area lights)
int var = int(std::min(sampler->next1D()*nLights, float(nLights) - 1.0f));
const areaLight* curLight = static_cast<const areaLight *> (lights[var]);
//sample a photon
Photon curPhoton;
Vector3f unQuantDir(0.0f,0.0f,0.0f);
curLight->samplePhoton(sampler, curPhoton, 1, nLights, unQuantDir);
Color3f alpha = curPhoton.getPower();
Color3f tp(1.0f, 1.0f, 1.0f);
//trace the photon
Intersection its;
Ray3f photonRay(curPhoton.getPosition(), unQuantDir);
m_shootedRays++;
if (scene->rayIntersect(photonRay, its)) {
while(true) {
const BSDF* curBSDF = its.mesh->getBSDF();
if (curBSDF->isDiffuse()) {
//store the photon
m_photonMap->push_back(Photon(
its.p /* Position */,
-photonRay.d /* Direction*/,
tp * alpha /* Power */
));
storedPhotons++;
}
if(!(storedPhotons < m_photonCount)) break;
BSDFQueryRecord query = BSDFQueryRecord(its.toLocal(-photonRay.d), Vector3f(0.0f), EMeasure::ESolidAngle);
Color3f fi = curBSDF->sample(query, sampler->next2D());
if(fi.maxCoeff() == 0.0f) break;
tp *= fi;
Vector3f wo = its.toWorld(query.wo);
photonRay = Ray3f(its.p, wo);
//ray escapes the scene
if (!scene->rayIntersect(photonRay, its)) break;
//stop critirium russian roulette
float q = tp.maxCoeff();
if(q < sampler->next1D()) break;
tp /= q;
}
}
if(onePercent != 0) {
if(storedPhotons % onePercent == 0){
int percent = int(floor(storedPhotons / onePercent));
if(percent % 10 == 0 && percentDone != percent){
percentDone = percent;
cout << percent << "%" << endl;
}
}
}
}
/* Build the photon map */
m_photonMap->build();
}
Color3f Li(const Scene *scene, Sampler *sampler, const Ray3f &ray) const {
/* Find the surface that is visible in the requested direction */
Intersection its;
//check if the ray intersects the scene
if (!scene->rayIntersect(ray, its)) {
return Color3f(0.0f);
}
Color3f tp(1.0f, 1.0f, 1.0f);
Color3f L(0.0f, 0.0f, 0.0f);
Ray3f pathRay(ray.o, ray.d);
while(true) {
//get the radiance of hitten object
if (its.mesh->isEmitter() ) {
const Emitter* areaLightEM = its.mesh->getEmitter();
const areaLight* aEM = static_cast<const areaLight *> (areaLightEM);
L += tp * aEM->sampleL(-pathRay.d, its.shFrame.n, its);
}
//get the asigned BSDF
const BSDF* curBSDF = its.mesh->getBSDF();
//transform to the local frame
BSDFQueryRecord query = BSDFQueryRecord(its.toLocal(-pathRay.d), Vector3f(0.0f), EMeasure::ESolidAngle);
//Normal3f n = its.shFrame.n;
if(curBSDF->isDiffuse()) {
std::vector<uint32_t> results;
m_photonMap->search(its.p, m_photonRadius, results);
Color3f Li(0.0f, 0.0f, 0.0f);
int k = results.size();
//cout << k << endl;
if(k > 0) {
//cout << results.size() << " Photons found!" << endl;
//get the power from all photons
//for (uint32_t i : results)
//const Photon &photonk = (*m_photonMap)[k-1];
Color3f Lindir(0.0f, 0.0f, 0.0f);
for (int i = 0; i < k; ++i)
{
const Photon &photon = (*m_photonMap)[results[i]];
Vector3f wi = its.toLocal(photon.getDirection());
Vector3f wo = its.toLocal(its.shFrame.n);
BSDFQueryRecord dummy = BSDFQueryRecord(wi, wo, EMeasure::ESolidAngle);
Color3f f = curBSDF->eval(dummy);
Lindir += (tp * f) * photon.getPower() / (M_PI * m_photonRadius * m_photonRadius);
}
Li += Lindir;
//cout << "Li = " << Li.toString() << endl;
if(Li.maxCoeff() > 0.0f)
L += Li / m_shootedRays;
}
break;
}
//sample the BRDF
Color3f fi = curBSDF->sample(query, sampler->next2D());
//check for black brdf
if(fi.maxCoeff() > 0.0f) {
tp *= fi;
} else {
//stop
// hit a black brdf
break;
}
Vector3f wo = its.toWorld(query.wo);
pathRay = Ray3f(its.p, wo);
//ray escapes the scene
if (!scene->rayIntersect(pathRay, its)) break;
//stop critirium russian roulette
float maxCoeff = tp.maxCoeff();
float q = std::min(0.99f, maxCoeff);
if(q < sampler->next1D()) break;
tp /= q;
}
return L;
}
Color3f Li(const Scene *scene, Sampler *sampler, const Ray3f &ray) const {
/* Find the surface that is visible in the requested direction */
Intersection its;
if (!scene->rayIntersect(ray, its))
return Color3f(0.0f);
//get the Normal at the intersection point
Vector3f n = Vector3f(its.shFrame.n);
//get the Number of lights from the scene
const std::vector<Emitter *> lights = scene->getEmitters();
uint32_t nLights = lights.size();
//check for lights
if(nLights > 0) {
//get the asigned BSDF
const BSDF* curBSDF = its.mesh->getBSDF();
if(curBSDF) {
Color3f totalLight(0.0f);
//uterated over all lights
//std::cout << "start light comp" << std::endl;
for (uint32_t var = 0; var < nLights; ++var) {
VisibilityTester vis;
Vector3f wi;
float pdf;
const Point2f ls;
//sample the light
Color3f Ld =lights[var]->sampleL(its.p, Epsilon, ls, &wi, &pdf, &vis);
//check if the light is visible
if(vis.Unoccluded(scene)) {
//create a query for the brdf
Vector3f wo = - ray.d;
//calculate the abs value of n dot wi
float costerm = n.dot(wi);
//transform to the local frame
wo = its.toLocal(wo);
wi = its.toLocal(wi);
const BSDFQueryRecord query = BSDFQueryRecord(wi, wo, EMeasure::ESolidAngle);
//calculate the BSDF
Color3f f = curBSDF->eval(query);
//add the light up
totalLight += (Ld * f * std::abs(costerm));
}
}
return totalLight;
}
}
return Color3f(0.0f);
}