Spectrum FresnelSpecular::Sample_f(const Vector3f &wo, Vector3f *wi,
const Point2f &u, Float *pdf,
BxDFType *sampledType) const {
Float F = FrDielectric(CosTheta(wo), etaA, etaB);
if (u[0] < F) {
// Compute specular reflection for _FresnelSpecular_
// Compute perfect specular reflection direction
*wi = Vector3f(-wo.x, -wo.y, wo.z);
if (sampledType)
*sampledType = BxDFType(BSDF_SPECULAR | BSDF_REFLECTION);
*pdf = F;
return F * R / AbsCosTheta(*wi);
} else {
// Compute specular transmission for _FresnelSpecular_
// Figure out which $\eta$ is incident and which is transmitted
bool entering = CosTheta(wo) > 0;
Float etaI = entering ? etaA : etaB;
Float etaT = entering ? etaB : etaA;
// Compute ray direction for specular transmission
if (!Refract(wo, Faceforward(Normal3f(0, 0, 1), wo), etaI / etaT, wi))
return 0;
Spectrum ft = T * (1 - F);
// Account for non-symmetry with transmission to different medium
if (mode == TransportMode::Radiance)
ft *= (etaI * etaI) / (etaT * etaT);
if (sampledType)
*sampledType = BxDFType(BSDF_SPECULAR | BSDF_TRANSMISSION);
*pdf = 1 - F;
return ft / AbsCosTheta(*wi);
}
}
// SurfaceInteraction Method Definitions
SurfaceInteraction::SurfaceInteraction(
const Point3f &p, const Vector3f &pError, const Point2f &uv,
const Vector3f &wo, const Vector3f &dpdu, const Vector3f &dpdv,
const Normal3f &dndu, const Normal3f &dndv, Float time, const Shape *shape)
: Interaction(p, Normal3f(Normalize(Cross(dpdu, dpdv))), pError, wo, time,
nullptr),
uv(uv),
dpdu(dpdu),
dpdv(dpdv),
dndu(dndu),
dndv(dndv),
shape(shape) {
// Initialize shading geometry from true geometry
shading.n = n;
shading.dpdu = dpdu;
shading.dpdv = dpdv;
shading.dndu = dndu;
shading.dndv = dndv;
// Adjust normal based on orientation and handedness
if (shape &&
(shape->reverseOrientation ^ shape->transformSwapsHandedness)) {
n *= -1;
shading.n *= -1;
}
}
void ParamSetProxy::AddNormal3f(const std::string& name, std::vector<Float> values) {
std::vector<Normal3f> v;
for (size_t i = 0; i < values.size() - 2; i+=3) {
v.push_back(Normal3f(values[i], values[i + 1], values[i + 2]));
}
ArrayView<Normal3f>* arrayView = new ArrayView<Normal3f>(v);
paramSet->AddNormal3f(name, std::move(arrayView->v), arrayView->size);
delete arrayView;
}
bool Sphere::Sample(const Point2f &sample, Interaction *it) const {
Point3f pObj = Point3f(0, 0, 0) + radius * UniformSampleSphere(sample);
it->n = Normalize((*ObjectToWorld)(Normal3f(pObj.x, pObj.y, pObj.z)));
if (ReverseOrientation) it->n *= -1.f;
Vector3f pObjError =
16.f * MachineEpsilon * Vector3f(radius, radius, radius);
it->p = (*ObjectToWorld)(pObj, pObjError, &it->pError);
return true;
}
bool Disk::Sample(const Point2f &sample, Interaction *it) const {
Point2f pd = ConcentricSampleDisk(sample);
Point3f pObj(pd.x * radius, pd.y * radius, height);
it->n = Normalize((*ObjectToWorld)(Normal3f(0, 0, 1)));
if (ReverseOrientation) it->n *= -1.f;
Vector3f pObjError(0.f, 0.f, MachineEpsilon * height);
it->p = (*ObjectToWorld)(pObj, pObjError, &it->pError);
return true;
}
Interaction Sphere::Sample(const Point2f &u) const {
Interaction it;
Point3f pObj = Point3f(0, 0, 0) + radius * UniformSampleSphere(u);
it.n = Normalize((*ObjectToWorld)(Normal3f(pObj.x, pObj.y, pObj.z)));
if (reverseOrientation) it.n *= -1.f;
// Reproject _pObj_ to sphere surface and compute _pObjError_
pObj *= radius / Distance(pObj, Point3f(0, 0, 0));
Vector3f pObjError = gamma(5) * Abs((Vector3f)pObj);
it.p = (*ObjectToWorld)(pObj, pObjError, &it.pError);
return it;
}
Interaction Cylinder::Sample(const Point2f &u) const {
Interaction it;
Float z = Lerp(u[0], zMin, zMax);
Float t = u[1] * phiMax;
Point3f pObj = Point3f(radius * std::cos(t), radius * std::sin(t), z);
it.n = Normalize((*ObjectToWorld)(Normal3f(pObj.x, pObj.y, 0)));
if (reverseOrientation) it.n *= -1.f;
// Reproject _pObj_ to cylinder surface and compute _pObjError_
Float hitRad = std::sqrt(pObj.x * pObj.x + pObj.y * pObj.y);
pObj.x *= radius / hitRad;
pObj.y *= radius / hitRad;
Vector3f pObjError = gamma(3) * Abs(Vector3f(pObj.x, pObj.y, 0));
it.p = (*ObjectToWorld)(pObj, pObjError, &it.pError);
return it;
}
Spectrum SpecularTransmission::Sample_f(const Vector3f &wo, Vector3f *wi,
const Point2f &sample, Float *pdf,
BxDFType *sampledType) const {
// Figure out which $\eta$ is incident and which is transmitted
bool entering = CosTheta(wo) > 0;
Float etaI = entering ? etaA : etaB;
Float etaT = entering ? etaB : etaA;
// Compute ray direction for specular transmission
if (!Refract(wo, Faceforward(Normal3f(0, 0, 1), wo), etaI / etaT, wi))
return 0;
*pdf = 1;
Spectrum ft = T * (Spectrum(1.) - fresnel.Evaluate(CosTheta(*wi)));
// Account for non-symmetry with transmission to different medium
if (mode == TransportMode::Radiance) ft *= (etaI * etaI) / (etaT * etaT);
return ft / AbsCosTheta(*wi);
}
Interaction Sphere::Sample(const Interaction &ref, const Point2f &u) const {
// Compute coordinate system for sphere sampling
Point3f pCenter = (*ObjectToWorld)(Point3f(0, 0, 0));
Vector3f wc = Normalize(pCenter - ref.p);
Vector3f wcX, wcY;
CoordinateSystem(wc, &wcX, &wcY);
// Sample uniformly on sphere if $\pt{}$ is inside it
Point3f pOrigin =
OffsetRayOrigin(ref.p, ref.pError, ref.n, pCenter - ref.p);
if (DistanceSquared(pOrigin, pCenter) <= radius * radius) return Sample(u);
// Sample sphere uniformly inside subtended cone
// Compute $\theta$ and $\phi$ values for sample in cone
Float sinThetaMax2 = radius * radius / DistanceSquared(ref.p, pCenter);
Float cosThetaMax = std::sqrt(std::max((Float)0, 1 - sinThetaMax2));
Float cosTheta = (1 - u[0]) + u[0] * cosThetaMax;
Float sinTheta = std::sqrt(1 - cosTheta * cosTheta);
Float phi = u[1] * 2 * Pi;
// Compute angle $\alpha$ from center of sphere to sampled point on surface
Float dc = Distance(ref.p, pCenter);
Float ds = dc * cosTheta -
std::sqrt(std::max(
(Float)0, radius * radius - dc * dc * sinTheta * sinTheta));
Float cosAlpha = (dc * dc + radius * radius - ds * ds) / (2 * dc * radius);
Float sinAlpha = std::sqrt(std::max((Float)0, 1 - cosAlpha * cosAlpha));
// Compute surface normal and sampled point on sphere
Vector3f nObj =
SphericalDirection(sinAlpha, cosAlpha, phi, -wcX, -wcY, -wc);
Point3f pObj = radius * Point3f(nObj.x, nObj.y, nObj.z);
// Return _Interaction_ for sampled point on sphere
Interaction it;
// Reproject _pObj_ to sphere surface and compute _pObjError_
pObj *= radius / Distance(pObj, Point3f(0, 0, 0));
Vector3f pObjError = gamma(5) * Abs((Vector3f)pObj);
it.p = (*ObjectToWorld)(pObj, pObjError, &it.pError);
it.n = (*ObjectToWorld)(Normal3f(nObj));
if (reverseOrientation) it.n *= -1.f;
return it;
}
ArbitraryMeshVertex MD2Vertex_construct( const md2Header_t* pHeader, const md2Frame_t* pFrame, const md2XyzNormal_t* xyz, const md2St_t* st ){
return ArbitraryMeshVertex(
Vertex3f(
xyz->v[0] * pFrame->scale[0] + pFrame->translate[0],
xyz->v[1] * pFrame->scale[1] + pFrame->translate[1],
xyz->v[2] * pFrame->scale[2] + pFrame->translate[2]
),
Normal3f(
g_mdl_normals[xyz->lightnormalindex][0],
g_mdl_normals[xyz->lightnormalindex][1],
g_mdl_normals[xyz->lightnormalindex][2]
),
TexCoord2f(
(float)st->s / pHeader->skinwidth,
(float)st->t / pHeader->skinheight
)
);
}
inline ArbitraryMeshVertex MDLVertex_construct( const mdlHeader_t& header, const mdlXyzNormal_t& xyz, const mdlSt_t& st, bool facesfront ){
return ArbitraryMeshVertex(
Vertex3f(
xyz.v[0] * header.scale[0] + header.scale_origin[0],
xyz.v[1] * header.scale[1] + header.scale_origin[1],
xyz.v[2] * header.scale[2] + header.scale_origin[2]
),
Normal3f(
g_mdl_normals[xyz.lightnormalindex][0],
g_mdl_normals[xyz.lightnormalindex][1],
g_mdl_normals[xyz.lightnormalindex][2]
),
TexCoord2f(
( (float)st.s / header.skinwidth ) + ( ( st.onseam == MDL_ONSEAM && !facesfront ) ? 0.5f : 0.0f ),
(float)st.t / header.skinheight
)
);
}
bool RealisticCamera::IntersectSphericalElement(Float radius, Float zCenter,
const Ray &ray, Float *t,
Normal3f *n) {
// Compute _t0_ and _t1_ for ray--element intersection
Point3f o = ray.o - Vector3f(0, 0, zCenter);
Float A = ray.d.x * ray.d.x + ray.d.y * ray.d.y + ray.d.z * ray.d.z;
Float B = 2 * (ray.d.x * o.x + ray.d.y * o.y + ray.d.z * o.z);
Float C = o.x * o.x + o.y * o.y + o.z * o.z - radius * radius;
Float t0, t1;
if (!Quadratic(A, B, C, &t0, &t1)) return false;
// Select intersection $t$ based on ray direction and element curvature
bool useCloserT = (ray.d.z > 0) ^ (radius < 0);
*t = useCloserT ? std::min(t0, t1) : std::max(t0, t1);
if (*t < 0) return false;
// Compute surface normal of element at ray intersection point
*n = Normal3f(Vector3f(o + *t * ray.d));
*n = Faceforward(Normalize(*n), -ray.d);
return true;
}
void normalquantisation_draw()
{
glPointSize(1);
glBegin(GL_POINTS);
for(std::size_t i = 0; i <= c_quantise_normal; ++i)
{
for(std::size_t j = 0; j <= c_quantise_normal; ++j)
{
Normal3f vertex(normal3f_normalised(Normal3f(
static_cast<float>(c_quantise_normal - j - i),
static_cast<float>(i),
static_cast<float>(j)
)));
VectorScale(normal3f_to_array(vertex), 64.f, normal3f_to_array(vertex));
glVertex3fv(normal3f_to_array(vertex));
vertex.x = -vertex.x;
glVertex3fv(normal3f_to_array(vertex));
}
}
glEnd();
}
void MD5Surface::buildVertexNormals()
{
for (Indices::iterator j = _indices.begin(); j != _indices.end(); j += 3)
{
ArbitraryMeshVertex& a = _vertices[*(j + 0)];
ArbitraryMeshVertex& b = _vertices[*(j + 1)];
ArbitraryMeshVertex& c = _vertices[*(j + 2)];
Vector3 weightedNormal((c.vertex - a.vertex).crossProduct(b.vertex - a.vertex));
a.normal += weightedNormal;
b.normal += weightedNormal;
c.normal += weightedNormal;
}
// Normalise all normal vectors
for (Vertices::iterator j = _vertices.begin(); j != _vertices.end(); ++j)
{
j->normal = Normal3f(j->normal.getNormalised());
}
}
void MD5Surface::updateToSkeleton(const MD5Skeleton& skeleton)
{
// Ensure we have all vertices allocated
if (_vertices.size() != _mesh->vertices.size())
{
_vertices.resize(_mesh->vertices.size());
}
// Deform vertices to fit the skeleton
for (std::size_t j = 0; j < _mesh->vertices.size(); ++j)
{
MD5Vert& vert = _mesh->vertices[j];
Vector3 skinned(0, 0, 0);
for (std::size_t k = 0; k != vert.weight_count; ++k)
{
MD5Weight& weight = _mesh->weights[vert.weight_index + k];
const IMD5Anim::Key& key = skeleton.getKey(weight.joint);
//const Joint& joint = skeleton.getJoint(weight.joint);
Vector3 rotatedPoint = key.orientation.transformPoint(weight.v);
skinned += (rotatedPoint + key.origin) * weight.t;
}
_vertices[j].vertex = skinned;
_vertices[j].texcoord = TexCoord2f(vert.u, vert.v);
_vertices[j].normal = Normal3f(0,0,0);
}
// Ensure the index array is ok
if (_indices.empty())
{
buildIndexArray();
}
buildVertexNormals();
updateGeometry();
}
Interaction Triangle::Sample(const Point2f &u) const {
Point2f b = UniformSampleTriangle(u);
// Get triangle vertices in _p0_, _p1_, and _p2_
const Point3f &p0 = mesh->p[v[0]];
const Point3f &p1 = mesh->p[v[1]];
const Point3f &p2 = mesh->p[v[2]];
Interaction it;
it.p = b[0] * p0 + b[1] * p1 + (1 - b[0] - b[1]) * p2;
// Compute surface normal for sampled point on triangle
if (mesh->n)
it.n = Normalize(b[0] * mesh->n[v[0]] + b[1] * mesh->n[v[1]] +
(1 - b[0] - b[1]) * mesh->n[v[2]]);
else
it.n = Normalize(Normal3f(Cross(p1 - p0, p2 - p0)));
if (reverseOrientation) it.n *= -1;
// Compute error bounds for sampled point on triangle
Point3f pAbsSum =
Abs(b[0] * p0) + Abs(b[1] * p1) + Abs((1 - b[0] - b[1]) * p2);
it.pError = gamma(6) * Vector3f(pAbsSum.x, pAbsSum.y, pAbsSum.z);
return it;
}
Spectrum PerspectiveCamera::Sample_Wi(const Interaction &ref, const Point2f &u,
Vector3f *wi, Float *pdf,
Point2f *pRaster,
VisibilityTester *vis) const {
// Uniformly sample a lens interaction _lensIntr_
Point2f pLens = lensRadius * ConcentricSampleDisk(u);
Point3f pLensWorld = CameraToWorld(ref.time, Point3f(pLens.x, pLens.y, 0));
Interaction lensIntr(pLensWorld, ref.time, medium);
lensIntr.n = Normal3f(CameraToWorld(ref.time, Vector3f(0, 0, 1)));
// Populate arguments and compute the importance value
*vis = VisibilityTester(ref, lensIntr);
*wi = lensIntr.p - ref.p;
Float dist = wi->Length();
*wi /= dist;
// Compute PDF for importance arriving at _ref_
// Compute lens area of perspective camera
Float lensArea = lensRadius != 0 ? (Pi * lensRadius * lensRadius) : 1;
*pdf = (dist * dist) / (AbsDot(lensIntr.n, *wi) * lensArea);
return We(lensIntr, -*wi, pRaster);
}
void MD5Surface::updateToDefaultPose(const MD5Joints& joints)
{
if (_vertices.size() != _mesh->vertices.size())
{
_vertices.resize(_mesh->vertices.size());
}
for (std::size_t j = 0; j < _mesh->vertices.size(); ++j)
{
MD5Vert& vert = _mesh->vertices[j];
Vector3 skinned(0, 0, 0);
for (std::size_t k = 0; k != vert.weight_count; ++k)
{
MD5Weight& weight = _mesh->weights[vert.weight_index + k];
const MD5Joint& joint = joints[weight.joint];
Vector3 rotatedPoint = joint.rotation.transformPoint(weight.v);
skinned += (rotatedPoint + joint.position) * weight.t;
}
_vertices[j].vertex = skinned;
_vertices[j].texcoord = TexCoord2f(vert.u, vert.v);
_vertices[j].normal = Normal3f(0,0,0);
}
// Ensure the index array is ok
if (_indices.empty())
{
buildIndexArray();
}
buildVertexNormals();
updateGeometry();
}
// Constructor. Copy the provided picoSurface_t structure into this object
RenderablePicoSurface::RenderablePicoSurface (picoSurface_t* surf) :
_originalShaderName(""), _mappedShaderName("")
{
// Get the shader from the picomodel struct.
picoShader_t* shader = PicoGetSurfaceShader(surf);
if (shader != 0) {
_originalShaderName = PicoGetShaderName(shader);
}
// Capture the shader
_shader = GlobalShaderCache().capture(_originalShaderName);
if (_shader)
_mappedShaderName = _originalShaderName; // no skin at this time
// Get the number of vertices and indices, and reserve capacity in our vectors in advance
// by populating them with empty structs.
const int nVerts = PicoGetSurfaceNumVertexes(surf);
_nIndices = PicoGetSurfaceNumIndexes(surf);
_vertices.resize(nVerts);
_indices.resize(_nIndices);
// Stream in the vertex data from the raw struct, expanding the local AABB to include
// each vertex.
for (int vNum = 0; vNum < nVerts; ++vNum) {
Vertex3f vertex(PicoGetSurfaceXYZ(surf, vNum));
_localAABB.includePoint(vertex);
_vertices[vNum].vertex = vertex;
_vertices[vNum].normal = Normal3f(PicoGetSurfaceNormal(surf, vNum));
_vertices[vNum].texcoord = TexCoord2f(PicoGetSurfaceST(surf, 0, vNum));
}
// Stream in the index data
picoIndex_t* ind = PicoGetSurfaceIndexes(surf, 0);
for (unsigned int i = 0; i < _nIndices; i++)
_indices[i] = ind[i];
}
bool Cylinder::Intersect(const Ray &r, Float *tHit, SurfaceInteraction *isect,
bool testAlphaTexture) const {
Float phi;
Point3f pHit;
// Transform _Ray_ to object space
Vector3f oErr, dErr;
Ray ray = (*WorldToObject)(r, &oErr, &dErr);
// Compute quadratic cylinder coefficients
// Initialize _EFloat_ ray coordinate values
EFloat ox(ray.o.x, oErr.x), oy(ray.o.y, oErr.y), oz(ray.o.z, oErr.z);
EFloat dx(ray.d.x, dErr.x), dy(ray.d.y, dErr.y), dz(ray.d.z, dErr.z);
EFloat a = dx * dx + dy * dy;
EFloat b = 2 * (dx * ox + dy * oy);
EFloat c = ox * ox + oy * oy - EFloat(radius) * EFloat(radius);
// Solve quadratic equation for _t_ values
EFloat t0, t1;
if (!Quadratic(a, b, c, &t0, &t1)) return false;
// Check quadric shape _t0_ and _t1_ for nearest intersection
if (t0.UpperBound() > ray.tMax || t1.LowerBound() <= 0) return false;
EFloat tShapeHit = t0;
if (tShapeHit.LowerBound() <= 0) {
tShapeHit = t1;
if (tShapeHit.UpperBound() > ray.tMax) return false;
}
// Compute cylinder hit point and $\phi$
pHit = ray((Float)tShapeHit);
// Refine cylinder intersection point
Float hitRad = std::sqrt(pHit.x * pHit.x + pHit.y * pHit.y);
pHit.x *= radius / hitRad;
pHit.y *= radius / hitRad;
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0) phi += 2 * Pi;
// Test cylinder intersection against clipping parameters
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) {
if (tShapeHit == t1) return false;
tShapeHit = t1;
if (t1.UpperBound() > ray.tMax) return false;
// Compute cylinder hit point and $\phi$
pHit = ray((Float)tShapeHit);
// Refine cylinder intersection point
Float hitRad = std::sqrt(pHit.x * pHit.x + pHit.y * pHit.y);
pHit.x *= radius / hitRad;
pHit.y *= radius / hitRad;
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0) phi += 2 * Pi;
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) return false;
}
// Find parametric representation of cylinder hit
Float u = phi / phiMax;
Float v = (pHit.z - zMin) / (zMax - zMin);
// Compute cylinder $\dpdu$ and $\dpdv$
Vector3f dpdu(-phiMax * pHit.y, phiMax * pHit.x, 0);
Vector3f dpdv(0, 0, zMax - zMin);
// Compute cylinder $\dndu$ and $\dndv$
Vector3f d2Pduu = -phiMax * phiMax * Vector3f(pHit.x, pHit.y, 0);
Vector3f d2Pduv(0, 0, 0), d2Pdvv(0, 0, 0);
// Compute coefficients for fundamental forms
Float E = Dot(dpdu, dpdu);
Float F = Dot(dpdu, dpdv);
Float G = Dot(dpdv, dpdv);
Vector3f N = Normalize(Cross(dpdu, dpdv));
Float e = Dot(N, d2Pduu);
Float f = Dot(N, d2Pduv);
Float g = Dot(N, d2Pdvv);
// Compute $\dndu$ and $\dndv$ from fundamental form coefficients
Float invEGF2 = 1 / (E * G - F * F);
Normal3f dndu = Normal3f((f * F - e * G) * invEGF2 * dpdu +
(e * F - f * E) * invEGF2 * dpdv);
Normal3f dndv = Normal3f((g * F - f * G) * invEGF2 * dpdu +
(f * F - g * E) * invEGF2 * dpdv);
// Compute error bounds for cylinder intersection
Vector3f pError = gamma(3) * Abs(Vector3f(pHit.x, pHit.y, 0));
// Initialize _SurfaceInteraction_ from parametric information
*isect = (*ObjectToWorld)(SurfaceInteraction(pHit, pError, Point2f(u, v),
-ray.d, dpdu, dpdv, dndu, dndv,
ray.time, this));
// Update _tHit_ for quadric intersection
*tHit = (Float)tShapeHit;
return true;
}
// Constructor. Copy the provided picoSurface_t structure into this object
RenderablePicoSurface::RenderablePicoSurface(picoSurface_t* surf,
const std::string& fExt)
: _shaderName(""),
_dlRegular(0),
_dlProgramVcol(0),
_dlProgramNoVCol(0)
{
// Get the shader from the picomodel struct. If this is a LWO model, use
// the material name to select the shader, while for an ASE model the
// bitmap path should be used.
picoShader_t* shader = PicoGetSurfaceShader(surf);
std::string rawName = "";
if (shader != 0)
{
if (fExt == "lwo")
{
_shaderName = PicoGetShaderName(shader);
}
else if (fExt == "ase")
{
rawName = PicoGetShaderName(shader);
std::string rawMapName = PicoGetShaderMapName(shader);
_shaderName = cleanupShaderName(rawMapName);
}
}
// If shader not found, fallback to alternative if available
// _shaderName is empty if the ase material has no BITMAP
// materialIsValid is false if _shaderName is not an existing shader
if ((_shaderName.empty() || !GlobalMaterialManager().materialExists(_shaderName)) &&
!rawName.empty())
{
_shaderName = cleanupShaderName(rawName);
}
// Capturing the shader happens later on when we have a RenderSystem reference
// Get the number of vertices and indices, and reserve capacity in our
// vectors in advance by populating them with empty structs.
int nVerts = PicoGetSurfaceNumVertexes(surf);
_nIndices = PicoGetSurfaceNumIndexes(surf);
_vertices.resize(nVerts);
_indices.resize(_nIndices);
// Stream in the vertex data from the raw struct, expanding the local AABB
// to include each vertex.
for (int vNum = 0; vNum < nVerts; ++vNum) {
// Get the vertex position and colour
Vertex3f vertex(PicoGetSurfaceXYZ(surf, vNum));
// Expand the AABB to include this new vertex
_localAABB.includePoint(vertex);
_vertices[vNum].vertex = vertex;
_vertices[vNum].normal = Normal3f(PicoGetSurfaceNormal(surf, vNum));
_vertices[vNum].texcoord = TexCoord2f(PicoGetSurfaceST(surf, 0, vNum));
_vertices[vNum].colour =
getColourVector(PicoGetSurfaceColor(surf, 0, vNum));
}
// Stream in the index data
picoIndex_t* ind = PicoGetSurfaceIndexes(surf, 0);
for (unsigned int i = 0; i < _nIndices; i++)
_indices[i] = ind[i];
// Calculate the tangent and bitangent vectors
calculateTangents();
// Construct the DLs
createDisplayLists();
}
bool Curve::recursiveIntersect(const Ray &ray, Float *tHit,
SurfaceInteraction *isect, const Point3f cp[4],
const Transform &rayToObject, Float u0, Float u1,
int depth) const {
// Try to cull curve segment versus ray
// Compute bounding box of curve segment, _curveBounds_
Bounds3f curveBounds =
Union(Bounds3f(cp[0], cp[1]), Bounds3f(cp[2], cp[3]));
Float maxWidth = std::max(Lerp(u0, common->width[0], common->width[1]),
Lerp(u1, common->width[0], common->width[1]));
curveBounds = Expand(curveBounds, 0.5 * maxWidth);
// Compute bounding box of ray, _rayBounds_
Float rayLength = ray.d.Length();
Float zMax = rayLength * ray.tMax;
Bounds3f rayBounds(Point3f(0, 0, 0), Point3f(0, 0, zMax));
if (Overlaps(curveBounds, rayBounds) == false) return false;
if (depth > 0) {
// Split curve segment into sub-segments and test for intersection
Float uMid = 0.5f * (u0 + u1);
Point3f cpSplit[7];
SubdivideBezier(cp, cpSplit);
return (recursiveIntersect(ray, tHit, isect, &cpSplit[0], rayToObject,
u0, uMid, depth - 1) ||
recursiveIntersect(ray, tHit, isect, &cpSplit[3], rayToObject,
uMid, u1, depth - 1));
} else {
// Intersect ray with curve segment
// Test ray against segment endpoint boundaries
Vector2f segmentDirection = Point2f(cp[3]) - Point2f(cp[0]);
// Test sample point against tangent perpendicular at curve start
Float edge =
(cp[1].y - cp[0].y) * -cp[0].y + cp[0].x * (cp[0].x - cp[1].x);
if (edge < 0) return false;
// Test sample point against tangent perpendicular at curve end
// TODO: update to match the starting test.
Vector2f endTangent = Point2f(cp[2]) - Point2f(cp[3]);
if (Dot(segmentDirection, endTangent) < 0) endTangent = -endTangent;
if (Dot(endTangent, Vector2f(cp[3])) < 0) return false;
// Compute line $w$ that gives minimum distance to sample point
Float denom = Dot(segmentDirection, segmentDirection);
if (denom == 0) return false;
Float w = Dot(-Vector2f(cp[0]), segmentDirection) / denom;
// Compute $u$ coordinate of curve intersection point and _hitWidth_
Float u = Clamp(Lerp(w, u0, u1), u0, u1);
Float hitWidth = Lerp(u, common->width[0], common->width[1]);
Normal3f nHit;
if (common->type == CurveType::Ribbon) {
// Scale _hitWidth_ based on ribbon orientation
Float sin0 = std::sin((1 - u) * common->normalAngle) *
common->invSinNormalAngle;
Float sin1 =
std::sin(u * common->normalAngle) * common->invSinNormalAngle;
nHit = sin0 * common->n[0] + sin1 * common->n[1];
hitWidth *= AbsDot(nHit, -ray.d / rayLength);
}
// Test intersection point against curve width
Vector3f dpcdw;
Point3f pc = EvalBezier(cp, Clamp(w, 0, 1), &dpcdw);
Float ptCurveDist2 = pc.x * pc.x + pc.y * pc.y;
if (ptCurveDist2 > hitWidth * hitWidth * .25) return false;
if (pc.z < 0 || pc.z > zMax) return false;
// Compute $v$ coordinate of curve intersection point
Float ptCurveDist = std::sqrt(ptCurveDist2);
Float edgeFunc = dpcdw.x * -pc.y + pc.x * dpcdw.y;
Float v = (edgeFunc > 0.) ? 0.5f + ptCurveDist / hitWidth
: 0.5f - ptCurveDist / hitWidth;
// Compute hit _t_ and partial derivatives for curve intersection
if (tHit != nullptr) {
// FIXME: this tHit isn't quite right for ribbons...
*tHit = pc.z / rayLength;
// Compute error bounds for curve intersection
Vector3f pError(2 * hitWidth, 2 * hitWidth, 2 * hitWidth);
// Compute $\dpdu$ and $\dpdv$ for curve intersection
Vector3f dpdu, dpdv;
EvalBezier(common->cpObj, u, &dpdu);
if (common->type == CurveType::Ribbon)
dpdv = Normalize(Cross(nHit, dpdu)) * hitWidth;
else {
// Compute curve $\dpdv$ for flat and cylinder curves
Vector3f dpduPlane = (Inverse(rayToObject))(dpdu);
Vector3f dpdvPlane =
Normalize(Vector3f(-dpduPlane.y, dpduPlane.x, 0)) *
hitWidth;
if (common->type == CurveType::Cylinder) {
// Rotate _dpdvPlane_ to give cylindrical appearance
Float theta = Lerp(v, -90., 90.);
Transform rot = Rotate(-theta, dpduPlane);
dpdvPlane = rot(dpdvPlane);
}
dpdv = rayToObject(dpdvPlane);
}
*isect = (*ObjectToWorld)(SurfaceInteraction(
ray(pc.z), pError, Point2f(u, v), -ray.d, dpdu, dpdv,
Normal3f(0, 0, 0), Normal3f(0, 0, 0), ray.time, this));
}
++nHits;
return true;
}
}
bool Sphere::Intersect(const Ray &r, Float *tHit, SurfaceInteraction *isect,
bool testAlphaTexture) const {
Float phi;
Point3f pHit;
// Transform _Ray_ to object space
Vector3f oErr, dErr;
Ray ray = (*WorldToObject)(r, &oErr, &dErr);
// Compute quadratic sphere coefficients
// Initialize _EFloat_ ray coordinate values
EFloat ox(ray.o.x, oErr.x), oy(ray.o.y, oErr.y), oz(ray.o.z, oErr.z);
EFloat dx(ray.d.x, dErr.x), dy(ray.d.y, dErr.y), dz(ray.d.z, dErr.z);
EFloat a = dx * dx + dy * dy + dz * dz;
EFloat b = 2 * (dx * ox + dy * oy + dz * oz);
EFloat c = ox * ox + oy * oy + oz * oz - EFloat(radius) * EFloat(radius);
// Solve quadratic equation for _t_ values
EFloat t0, t1;
if (!Quadratic(a, b, c, &t0, &t1)) return false;
// Check quadric shape _t0_ and _t1_ for nearest intersection
if (t0.UpperBound() > ray.tMax || t1.LowerBound() <= 0) return false;
EFloat tShapeHit = t0;
if (tShapeHit.LowerBound() <= 0) {
tShapeHit = t1;
if (tShapeHit.UpperBound() > ray.tMax) return false;
}
// Compute sphere hit position and $\phi$
pHit = ray((Float)tShapeHit);
// Refine sphere intersection point
pHit *= radius / Distance(pHit, Point3f(0, 0, 0));
if (pHit.x == 0 && pHit.y == 0) pHit.x = 1e-5f * radius;
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0) phi += 2 * Pi;
// Test sphere intersection against clipping parameters
if ((zMin > -radius && pHit.z < zMin) || (zMax < radius && pHit.z > zMax) ||
phi > phiMax) {
if (tShapeHit == t1) return false;
if (t1.UpperBound() > ray.tMax) return false;
tShapeHit = t1;
// Compute sphere hit position and $\phi$
pHit = ray((Float)tShapeHit);
// Refine sphere intersection point
pHit *= radius / Distance(pHit, Point3f(0, 0, 0));
if (pHit.x == 0 && pHit.y == 0) pHit.x = 1e-5f * radius;
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0) phi += 2 * Pi;
if ((zMin > -radius && pHit.z < zMin) ||
(zMax < radius && pHit.z > zMax) || phi > phiMax)
return false;
}
// Find parametric representation of sphere hit
Float u = phi / phiMax;
Float theta = std::acos(Clamp(pHit.z / radius, -1, 1));
Float v = (theta - thetaMin) / (thetaMax - thetaMin);
// Compute sphere $\dpdu$ and $\dpdv$
Float zRadius = std::sqrt(pHit.x * pHit.x + pHit.y * pHit.y);
Float invZRadius = 1 / zRadius;
Float cosPhi = pHit.x * invZRadius;
Float sinPhi = pHit.y * invZRadius;
Vector3f dpdu(-phiMax * pHit.y, phiMax * pHit.x, 0);
Vector3f dpdv =
(thetaMax - thetaMin) *
Vector3f(pHit.z * cosPhi, pHit.z * sinPhi, -radius * std::sin(theta));
// Compute sphere $\dndu$ and $\dndv$
Vector3f d2Pduu = -phiMax * phiMax * Vector3f(pHit.x, pHit.y, 0);
Vector3f d2Pduv =
(thetaMax - thetaMin) * pHit.z * phiMax * Vector3f(-sinPhi, cosPhi, 0.);
Vector3f d2Pdvv = -(thetaMax - thetaMin) * (thetaMax - thetaMin) *
Vector3f(pHit.x, pHit.y, pHit.z);
// Compute coefficients for fundamental forms
Float E = Dot(dpdu, dpdu);
Float F = Dot(dpdu, dpdv);
Float G = Dot(dpdv, dpdv);
Vector3f N = Normalize(Cross(dpdu, dpdv));
Float e = Dot(N, d2Pduu);
Float f = Dot(N, d2Pduv);
Float g = Dot(N, d2Pdvv);
// Compute $\dndu$ and $\dndv$ from fundamental form coefficients
Float invEGF2 = 1 / (E * G - F * F);
Normal3f dndu = Normal3f((f * F - e * G) * invEGF2 * dpdu +
(e * F - f * E) * invEGF2 * dpdv);
Normal3f dndv = Normal3f((g * F - f * G) * invEGF2 * dpdu +
(f * F - g * E) * invEGF2 * dpdv);
// Compute error bounds for sphere intersection
Vector3f pError = gamma(5) * Abs((Vector3f)pHit);
// Initialize _SurfaceInteraction_ from parametric information
*isect = (*ObjectToWorld)(SurfaceInteraction(pHit, pError, Point2f(u, v),
-ray.d, dpdu, dpdv, dndu, dndv,
ray.time, this));
// Update _tHit_ for quadric intersection
*tHit = (Float)tShapeHit;
return true;
}
static Normal3f normalise(float x, float y, float z)
{
return normal3f_normalised(Normal3f(x, y, z));
}
bool Hyperboloid::Intersect(const Ray &r, Float *tHit,
SurfaceInteraction *isect) const {
Float phi, v;
Point3f pHit;
// Transform _Ray_ to object space
Vector3f oErr, dErr;
Ray ray = (*WorldToObject)(r, &oErr, &dErr);
// Compute quadratic hyperboloid coefficients
// Initialize _EFloat_ ray coordinate values
EFloat ox(ray.o.x, oErr.x), oy(ray.o.y, oErr.y), oz(ray.o.z, oErr.z);
EFloat dx(ray.d.x, dErr.x), dy(ray.d.y, dErr.y), dz(ray.d.z, dErr.z);
EFloat a = ah * dx * dx + ah * dy * dy - ch * dz * dz;
EFloat b = 2.f * (ah * dx * ox + ah * dy * oy - ch * dz * oz);
EFloat c = ah * ox * ox + ah * oy * oy - ch * oz * oz - 1.f;
// Solve quadratic equation for _t_ values
EFloat t0, t1;
if (!Quadratic(a, b, c, &t0, &t1)) return false;
// Check quadric shape _t0_ and _t1_ for nearest intersection
if (t0.UpperBound() > ray.tMax || t1.LowerBound() <= 0) return false;
EFloat tShapeHit = t0;
if (t0.LowerBound() <= 0) {
tShapeHit = t1;
if (tShapeHit.UpperBound() > ray.tMax) return false;
}
// Compute hyperboloid inverse mapping
pHit = ray((Float)tShapeHit);
v = (pHit.z - p1.z) / (p2.z - p1.z);
Point3f pr = (1 - v) * p1 + v * p2;
phi = std::atan2(pr.x * pHit.y - pHit.x * pr.y,
pHit.x * pr.x + pHit.y * pr.y);
if (phi < 0) phi += 2 * Pi;
// Test hyperboloid intersection against clipping parameters
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) {
if (tShapeHit == t1) return false;
tShapeHit = t1;
if (t1.UpperBound() > ray.tMax) return false;
// Compute hyperboloid inverse mapping
pHit = ray((Float)tShapeHit);
v = (pHit.z - p1.z) / (p2.z - p1.z);
Point3f pr = (1 - v) * p1 + v * p2;
phi = std::atan2(pr.x * pHit.y - pHit.x * pr.y,
pHit.x * pr.x + pHit.y * pr.y);
if (phi < 0) phi += 2 * Pi;
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) return false;
}
// Compute parametric representation of hyperboloid hit
Float u = phi / phiMax;
// Compute hyperboloid $\dpdu$ and $\dpdv$
Float cosPhi = std::cos(phi), sinPhi = std::sin(phi);
Vector3f dpdu(-phiMax * pHit.y, phiMax * pHit.x, 0.);
Vector3f dpdv((p2.x - p1.x) * cosPhi - (p2.y - p1.y) * sinPhi,
(p2.x - p1.x) * sinPhi + (p2.y - p1.y) * cosPhi, p2.z - p1.z);
// Compute hyperboloid $\dndu$ and $\dndv$
Vector3f d2Pduu = -phiMax * phiMax * Vector3f(pHit.x, pHit.y, 0);
Vector3f d2Pduv = phiMax * Vector3f(-dpdv.y, dpdv.x, 0.);
Vector3f d2Pdvv(0, 0, 0);
// Compute coefficients for fundamental forms
Float E = Dot(dpdu, dpdu);
Float F = Dot(dpdu, dpdv);
Float G = Dot(dpdv, dpdv);
Vector3f N = Normalize(Cross(dpdu, dpdv));
Float e = Dot(N, d2Pduu);
Float f = Dot(N, d2Pduv);
Float g = Dot(N, d2Pdvv);
// Compute $\dndu$ and $\dndv$ from fundamental form coefficients
Float invEGF2 = 1 / (E * G - F * F);
Normal3f dndu = Normal3f((f * F - e * G) * invEGF2 * dpdu +
(e * F - f * E) * invEGF2 * dpdv);
Normal3f dndv = Normal3f((g * F - f * G) * invEGF2 * dpdu +
(f * F - g * E) * invEGF2 * dpdv);
// Compute error bounds for hyperboloid intersection
// Compute error bounds for intersection computed with ray equation
EFloat px = ox + tShapeHit * dx;
EFloat py = oy + tShapeHit * dy;
EFloat pz = oz + tShapeHit * dz;
Vector3f pError = Vector3f(px.GetAbsoluteError(), py.GetAbsoluteError(),
pz.GetAbsoluteError());
// Initialize _SurfaceInteraction_ from parametric information
*isect = (*ObjectToWorld)(SurfaceInteraction(pHit, pError, Point2f(u, v),
-ray.d, dpdu, dpdv, dndu, dndv,
ray.time, this));
*tHit = (Float)tShapeHit;
return true;
}
bool Paraboloid::Intersect(const Ray &r, Float *tHit,
SurfaceInteraction *isect) const {
Float phi;
Point3f pHit;
// Transform _Ray_ to object space
Vector3f oErr, dErr;
Ray ray = (*WorldToObject)(r, &oErr, &dErr);
// Compute quadratic paraboloid coefficients
// Initialize _EFloat_ ray coordinate values
EFloat ox(ray.o.x, oErr.x), oy(ray.o.y, oErr.y), oz(ray.o.z, oErr.z);
EFloat dx(ray.d.x, dErr.x), dy(ray.d.y, dErr.y), dz(ray.d.z, dErr.z);
EFloat k = EFloat(zMax) / (EFloat(radius) * EFloat(radius));
EFloat a = k * (dx * dx + dy * dy);
EFloat b = 2.f * k * (dx * ox + dy * oy) - dz;
EFloat c = k * (ox * ox + oy * oy) - oz;
// Solve quadratic equation for _t_ values
EFloat t0, t1;
if (!Quadratic(a, b, c, &t0, &t1)) return false;
// Check quadric shape _t0_ and _t1_ for nearest intersection
if (t0.UpperBound() > ray.tMax || t1.LowerBound() <= 0) return false;
EFloat tShapeHit = t0;
if (tShapeHit.LowerBound() <= 0) {
tShapeHit = t1;
if (tShapeHit.UpperBound() > ray.tMax) return false;
}
// Compute paraboloid inverse mapping
pHit = ray((Float)tShapeHit);
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0.) phi += 2 * Pi;
// Test paraboloid intersection against clipping parameters
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) {
if (tShapeHit == t1) return false;
tShapeHit = t1;
if (t1.UpperBound() > ray.tMax) return false;
// Compute paraboloid inverse mapping
pHit = ray((Float)tShapeHit);
phi = std::atan2(pHit.y, pHit.x);
if (phi < 0.) phi += 2 * Pi;
if (pHit.z < zMin || pHit.z > zMax || phi > phiMax) return false;
}
// Find parametric representation of paraboloid hit
Float u = phi / phiMax;
Float v = (pHit.z - zMin) / (zMax - zMin);
// Compute paraboloid $\dpdu$ and $\dpdv$
Vector3f dpdu(-phiMax * pHit.y, phiMax * pHit.x, 0.);
Vector3f dpdv = (zMax - zMin) *
Vector3f(pHit.x / (2 * pHit.z), pHit.y / (2 * pHit.z), 1.);
// Compute paraboloid $\dndu$ and $\dndv$
Vector3f d2Pduu = -phiMax * phiMax * Vector3f(pHit.x, pHit.y, 0);
Vector3f d2Pduv =
(zMax - zMin) * phiMax *
Vector3f(-pHit.y / (2 * pHit.z), pHit.x / (2 * pHit.z), 0);
Vector3f d2Pdvv = -(zMax - zMin) * (zMax - zMin) *
Vector3f(pHit.x / (4 * pHit.z * pHit.z),
pHit.y / (4 * pHit.z * pHit.z), 0.);
// Compute coefficients for fundamental forms
Float E = Dot(dpdu, dpdu);
Float F = Dot(dpdu, dpdv);
Float G = Dot(dpdv, dpdv);
Vector3f N = Normalize(Cross(dpdu, dpdv));
Float e = Dot(N, d2Pduu);
Float f = Dot(N, d2Pduv);
Float g = Dot(N, d2Pdvv);
// Compute $\dndu$ and $\dndv$ from fundamental form coefficients
Float invEGF2 = 1 / (E * G - F * F);
Normal3f dndu = Normal3f((f * F - e * G) * invEGF2 * dpdu +
(e * F - f * E) * invEGF2 * dpdv);
Normal3f dndv = Normal3f((g * F - f * G) * invEGF2 * dpdu +
(f * F - g * E) * invEGF2 * dpdv);
// Compute error bounds for paraboloid intersection
// Compute error bounds for intersection computed with ray equation
EFloat px = ox + tShapeHit * dx;
EFloat py = oy + tShapeHit * dy;
EFloat pz = oz + tShapeHit * dz;
Vector3f pError = Vector3f(px.GetAbsoluteError(), py.GetAbsoluteError(),
pz.GetAbsoluteError());
// Initialize _SurfaceInteraction_ from parametric information
*isect = (*ObjectToWorld)(SurfaceInteraction(pHit, pError, Point2f(u, v),
-ray.d, dpdu, dpdv, dndu, dndv,
ray.time, this));
*tHit = (Float)tShapeHit;
return true;
}
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;
}
std::vector<std::shared_ptr<Shape>> CreateNURBS(const Transform *o2w,
const Transform *w2o,
bool reverseOrientation,
const ParamSet ¶ms) {
int nu = params.FindOneInt("nu", -1);
if (nu == -1) {
Error("Must provide number of control points \"nu\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
int uorder = params.FindOneInt("uorder", -1);
if (uorder == -1) {
Error("Must provide u order \"uorder\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
int nuknots, nvknots;
const Float *uknots = params.FindFloat("uknots", &nuknots);
if (uknots == nullptr) {
Error("Must provide u knot vector \"uknots\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
if (nuknots != nu + uorder) {
Error(
"Number of knots in u knot vector %d doesn't match sum of "
"number of u control points %d and u order %d.",
nuknots, nu, uorder);
return std::vector<std::shared_ptr<Shape>>();
}
Float u0 = params.FindOneFloat("u0", uknots[uorder - 1]);
Float u1 = params.FindOneFloat("u1", uknots[nu]);
int nv = params.FindOneInt("nv", -1);
if (nv == -1) {
Error("Must provide number of control points \"nv\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
int vorder = params.FindOneInt("vorder", -1);
if (vorder == -1) {
Error("Must provide v order \"vorder\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
const Float *vknots = params.FindFloat("vknots", &nvknots);
if (vknots == nullptr) {
Error("Must provide v knot vector \"vknots\" with NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
if (nvknots != nv + vorder) {
Error(
"Number of knots in v knot vector %d doesn't match sum of "
"number of v control points %d and v order %d.",
nvknots, nv, vorder);
return std::vector<std::shared_ptr<Shape>>();
}
Float v0 = params.FindOneFloat("v0", vknots[vorder - 1]);
Float v1 = params.FindOneFloat("v1", vknots[nv]);
bool isHomogeneous = false;
int npts;
const Float *P = (const Float *)params.FindPoint3f("P", &npts);
if (!P) {
P = params.FindFloat("Pw", &npts);
if (!P) {
Error(
"Must provide control points via \"P\" or \"Pw\" parameter to "
"NURBS shape.");
return std::vector<std::shared_ptr<Shape>>();
}
if ((npts % 4) != 0) {
Error(
"Number of \"Pw\" control points provided to NURBS shape must "
"be "
"multiple of four");
return std::vector<std::shared_ptr<Shape>>();
}
npts /= 4;
isHomogeneous = true;
}
if (npts != nu * nv) {
Error("NURBS shape was expecting %dx%d=%d control points, was given %d",
nu, nv, nu * nv, npts);
return std::vector<std::shared_ptr<Shape>>();
}
// Compute NURBS dicing rates
int diceu = 30, dicev = 30;
std::unique_ptr<Float[]> ueval(new Float[diceu]);
std::unique_ptr<Float[]> veval(new Float[dicev]);
std::unique_ptr<Point3f[]> evalPs(new Point3f[diceu * dicev]);
std::unique_ptr<Normal3f[]> evalNs(new Normal3f[diceu * dicev]);
int i;
for (i = 0; i < diceu; ++i)
ueval[i] = Lerp((float)i / (float)(diceu - 1), u0, u1);
for (i = 0; i < dicev; ++i)
veval[i] = Lerp((float)i / (float)(dicev - 1), v0, v1);
// Evaluate NURBS over grid of points
memset(evalPs.get(), 0, diceu * dicev * sizeof(Point3f));
memset(evalNs.get(), 0, diceu * dicev * sizeof(Point3f));
std::unique_ptr<Point2f[]> uvs(new Point2f[diceu * dicev]);
// Turn NURBS into triangles
std::unique_ptr<Homogeneous3[]> Pw(new Homogeneous3[nu * nv]);
if (isHomogeneous) {
for (int i = 0; i < nu * nv; ++i) {
Pw[i].x = P[4 * i];
Pw[i].y = P[4 * i + 1];
Pw[i].z = P[4 * i + 2];
Pw[i].w = P[4 * i + 3];
}
} else {
for (int i = 0; i < nu * nv; ++i) {
Pw[i].x = P[3 * i];
Pw[i].y = P[3 * i + 1];
Pw[i].z = P[3 * i + 2];
Pw[i].w = 1.;
}
}
for (int v = 0; v < dicev; ++v) {
for (int u = 0; u < diceu; ++u) {
uvs[(v * diceu + u)].x = ueval[u];
uvs[(v * diceu + u)].y = veval[v];
Vector3f dpdu, dpdv;
Point3f pt = NURBSEvaluateSurface(uorder, uknots, nu, ueval[u],
vorder, vknots, nv, veval[v],
Pw.get(), &dpdu, &dpdv);
evalPs[v * diceu + u].x = pt.x;
evalPs[v * diceu + u].y = pt.y;
evalPs[v * diceu + u].z = pt.z;
evalNs[v * diceu + u] = Normal3f(Normalize(Cross(dpdu, dpdv)));
}
}
// Generate points-polygons mesh
int nTris = 2 * (diceu - 1) * (dicev - 1);
std::unique_ptr<int[]> vertices(new int[3 * nTris]);
int *vertp = vertices.get();
// Compute the vertex offset numbers for the triangles
for (int v = 0; v < dicev - 1; ++v) {
for (int u = 0; u < diceu - 1; ++u) {
#define VN(u, v) ((v)*diceu + (u))
*vertp++ = VN(u, v);
*vertp++ = VN(u + 1, v);
*vertp++ = VN(u + 1, v + 1);
*vertp++ = VN(u, v);
*vertp++ = VN(u + 1, v + 1);
*vertp++ = VN(u, v + 1);
#undef VN
}
}
int nVerts = diceu * dicev;
return CreateTriangleMesh(o2w, w2o, reverseOrientation, nTris,
vertices.get(), nVerts, evalPs.get(), nullptr,
evalNs.get(), uvs.get(), nullptr);
}
const Distribution1D *SpatialLightDistribution::Lookup(const Point3f &p) const {
ProfilePhase _(Prof::LightDistribLookup);
++nLookups;
// Compute integer voxel coordinates for the given point |p| with
// respect to the overall voxel grid.
Vector3f offset = scene.WorldBound().Offset(p); // offset in [0,1].
Point3i pi;
for (int i = 0; i < 3; ++i) pi[i] = int(offset[i] * nVoxels[i]);
// Create the per-thread cache of sampling distributions if needed.
LocalBucketHash *localVoxelDistribution =
localVoxelDistributions[ThreadIndex].get();
if (!localVoxelDistribution) {
LOG(INFO) << "Created per-thread SpatialLightDistribution for thread" <<
ThreadIndex;
localVoxelDistribution = new LocalBucketHash;
localVoxelDistributions[ThreadIndex].reset(localVoxelDistribution);
}
else {
// Otherwise see if we have a sampling distribution for the voxel
// that |p| is in already available in the local cache.
auto iter = localVoxelDistribution->find(pi);
if (iter != localVoxelDistribution->end())
return iter->second;
}
// Now we need to either get the distribution from the shared hash
// table (if another thread has already created it), or create it
// ourselves and add it to the shared table.
ProfilePhase __(Prof::LightDistribLookupL2);
// First, compute a hash into the first-level hash table.
size_t hash = std::hash<int>{}(pi[0] + nVoxels[0] * pi[1] +
nVoxels[0] * nVoxels[1] * pi[2]);
hash &= (nBuckets - 1);
// Acquire the lock for the corresponding second-level hash table.
std::lock_guard<std::mutex> lock(mutexes[hash]);
// See if we can find it.
auto iter = voxelDistribution[hash].find(pi);
if (iter != voxelDistribution[hash].end()) {
// Success. Add the pointer to the thread-specific hash table so
// that we can look up this distribution more efficiently in the
// future.
(*localVoxelDistribution)[pi] = iter->second.get();
return iter->second.get();
}
// We need to compute a new sampling distriibution for this voxel. Note
// that we're holding the lock for the first-level hash table bucket
// throughout the following; in general, we'd like to do the following
// quickly so that other threads don't get held up waiting for that
// lock (for this or other voxels that share it).
ProfilePhase ___(Prof::LightDistribCreation);
++nCreated;
++nDistributions;
// Compute the world-space bounding box of the voxel.
Point3f p0(Float(pi[0]) / Float(nVoxels[0]),
Float(pi[1]) / Float(nVoxels[1]),
Float(pi[2]) / Float(nVoxels[2]));
Point3f p1(Float(pi[0] + 1) / Float(nVoxels[0]),
Float(pi[1] + 1) / Float(nVoxels[1]),
Float(pi[2] + 1) / Float(nVoxels[2]));
Bounds3f voxelBounds(scene.WorldBound().Lerp(p0),
scene.WorldBound().Lerp(p1));
// Compute the sampling distribution. Sample a number of points inside
// voxelBounds using a 3D Halton sequence; at each one, sample each
// light source and compute a weight based on Li/pdf for the light's
// sample (ignoring visibility between the point in the voxel and the
// point on the light source) as an approximation to how much the light
// is likely to contribute to illumination in the voxel.
int nSamples = 128;
std::vector<Float> lightContrib(scene.lights.size(), Float(0));
for (int i = 0; i < nSamples; ++i) {
Point3f po = voxelBounds.Lerp(Point3f(
RadicalInverse(0, i), RadicalInverse(1, i), RadicalInverse(2, i)));
Interaction intr(po, Normal3f(), Vector3f(), Vector3f(1, 0, 0),
0 /* time */, MediumInterface());
// Use the next two Halton dimensions to sample a point on the
// light source.
Point2f u(RadicalInverse(3, i), RadicalInverse(4, i));
for (size_t j = 0; j < scene.lights.size(); ++j) {
Float pdf;
Vector3f wi;
VisibilityTester vis;
Spectrum Li = scene.lights[j]->Sample_Li(intr, u, &wi, &pdf, &vis);
if (pdf > 0) {
// TODO: look at tracing shadow rays / computing beam
// transmittance. Probably shouldn't give those full weight
// but instead e.g. have an occluded shadow ray scale down
// the contribution by 10 or something.
lightContrib[j] += Li.y() / pdf;
}
}
}
// We don't want to leave any lights with a zero probability; it's
// possible that a light contributes to points in the voxel even though
// we didn't find such a point when sampling above. Therefore, compute
// a minimum (small) weight and ensure that all lights are given at
// least the corresponding probability.
Float sumContrib =
std::accumulate(lightContrib.begin(), lightContrib.end(), Float(0));
Float avgContrib = sumContrib / (nSamples * lightContrib.size());
Float minContrib = (avgContrib > 0) ? .001 * avgContrib : 1;
for (size_t i = 0; i < lightContrib.size(); ++i) {
VLOG(2) << "Voxel pi = " << pi << ", light " << i << " contrib = "
<< lightContrib[i];
lightContrib[i] = std::max(lightContrib[i], minContrib);
}
LOG(INFO) << "Initialized light distribution in voxel pi= " << pi <<
", avgContrib = " << avgContrib;
// Compute a sampling distribution from the accumulated
// contributions.
std::unique_ptr<Distribution1D> distrib(
new Distribution1D(&lightContrib[0], lightContrib.size()));
// Store a pointer to it in the per-thread cache for the future.
(*localVoxelDistribution)[pi] = distrib.get();
// Store the canonical unique_ptr for it in the global hash table so
// other threads can use it.
voxelDistribution[hash][pi] = std::move(distrib);
return (*localVoxelDistribution)[pi];
}
Distribution1D *
SpatialLightDistribution::ComputeDistribution(Point3i pi) const {
ProfilePhase _(Prof::LightDistribCreation);
++nCreated;
++nDistributions;
// Compute the world-space bounding box of the voxel corresponding to
// |pi|.
Point3f p0(Float(pi[0]) / Float(nVoxels[0]),
Float(pi[1]) / Float(nVoxels[1]),
Float(pi[2]) / Float(nVoxels[2]));
Point3f p1(Float(pi[0] + 1) / Float(nVoxels[0]),
Float(pi[1] + 1) / Float(nVoxels[1]),
Float(pi[2] + 1) / Float(nVoxels[2]));
Bounds3f voxelBounds(scene.WorldBound().Lerp(p0),
scene.WorldBound().Lerp(p1));
// Compute the sampling distribution. Sample a number of points inside
// voxelBounds using a 3D Halton sequence; at each one, sample each
// light source and compute a weight based on Li/pdf for the light's
// sample (ignoring visibility between the point in the voxel and the
// point on the light source) as an approximation to how much the light
// is likely to contribute to illumination in the voxel.
int nSamples = 128;
std::vector<Float> lightContrib(scene.lights.size(), Float(0));
for (int i = 0; i < nSamples; ++i) {
Point3f po = voxelBounds.Lerp(Point3f(
RadicalInverse(0, i), RadicalInverse(1, i), RadicalInverse(2, i)));
Interaction intr(po, Normal3f(), Vector3f(), Vector3f(1, 0, 0),
0 /* time */, MediumInterface());
// Use the next two Halton dimensions to sample a point on the
// light source.
Point2f u(RadicalInverse(3, i), RadicalInverse(4, i));
for (size_t j = 0; j < scene.lights.size(); ++j) {
Float pdf;
Vector3f wi;
VisibilityTester vis;
Spectrum Li = scene.lights[j]->Sample_Li(intr, u, &wi, &pdf, &vis);
if (pdf > 0) {
// TODO: look at tracing shadow rays / computing beam
// transmittance. Probably shouldn't give those full weight
// but instead e.g. have an occluded shadow ray scale down
// the contribution by 10 or something.
lightContrib[j] += Li.y() / pdf;
}
}
}
// We don't want to leave any lights with a zero probability; it's
// possible that a light contributes to points in the voxel even though
// we didn't find such a point when sampling above. Therefore, compute
// a minimum (small) weight and ensure that all lights are given at
// least the corresponding probability.
Float sumContrib =
std::accumulate(lightContrib.begin(), lightContrib.end(), Float(0));
Float avgContrib = sumContrib / (nSamples * lightContrib.size());
Float minContrib = (avgContrib > 0) ? .001 * avgContrib : 1;
for (size_t i = 0; i < lightContrib.size(); ++i) {
VLOG(2) << "Voxel pi = " << pi << ", light " << i << " contrib = "
<< lightContrib[i];
lightContrib[i] = std::max(lightContrib[i], minContrib);
}
LOG(INFO) << "Initialized light distribution in voxel pi= " << pi <<
", avgContrib = " << avgContrib;
// Compute a sampling distribution from the accumulated contributions.
return new Distribution1D(&lightContrib[0], lightContrib.size());
}
