// InfiniteAreaLight Method Definitions
InfiniteAreaLight::InfiniteAreaLight(const Transform &LightToWorld,
const Spectrum &L, int nSamples,
const std::string &texmap)
: Light((int)LightFlags::Infinite, LightToWorld, MediumInterface(),
nSamples) {
// Read texel data from _texmap_ and initialize _Lmap_
Point2i resolution;
std::unique_ptr<RGBSpectrum[]> texels(nullptr);
if (texmap != "") {
texels = ReadImage(texmap, &resolution);
if (texels)
for (int i = 0; i < resolution.x * resolution.y; ++i)
texels[i] *= L.ToRGBSpectrum();
}
if (!texels) {
resolution.x = resolution.y = 1;
texels = std::unique_ptr<RGBSpectrum[]>(new RGBSpectrum[1]);
texels[0] = L.ToRGBSpectrum();
}
Lmap.reset(new MIPMap<RGBSpectrum>(resolution, texels.get()));
// Initialize sampling PDFs for infinite area light
// Compute scalar-valued image _img_ from environment map
int width = 2 * Lmap->Width(), height = 2 * Lmap->Height();
std::unique_ptr<Float[]> img(new Float[width * height]);
float fwidth = 0.5f / std::min(width, height);
ParallelFor(
[&](int64_t v) {
Float vp = (v + .5f) / (Float)height;
Float sinTheta = std::sin(Pi * (v + .5f) / height);
for (int u = 0; u < width; ++u) {
Float up = (u + .5f) / (Float)width;
img[u + v * width] = Lmap->Lookup(Point2f(up, vp), fwidth).y();
img[u + v * width] *= sinTheta;
}
},
height, 32);
// Compute sampling distributions for rows and columns of image
distribution.reset(new Distribution2D(img.get(), width, height));
}
// InfiniteAreaLight Method Definitions
InfiniteAreaLight::InfiniteAreaLight(const Transform &LightToWorld,
const Spectrum &L, int nSamples,
const std::string &texmap)
: Light(LightFlags::Infinite, LightToWorld, nullptr, nSamples) {
// Read texel data from _texmap_ and initialize _Lmap_
Point2i resolution;
std::unique_ptr<RGBSpectrum[]> texels(nullptr);
if (texmap != "") {
texels = ReadImage(texmap, &resolution);
if (texels)
for (int i = 0; i < resolution.x * resolution.y; ++i)
texels[i] *= L.ToRGBSpectrum();
}
if (!texels) {
resolution.x = resolution.y = 1;
texels = std::unique_ptr<RGBSpectrum[]>(new RGBSpectrum[1]);
texels[0] = L.ToRGBSpectrum();
}
Lmap.reset(new MIPMap<RGBSpectrum>(resolution, texels.get()));
// Initialize sampling PDFs for infinite area light
// Compute scalar-valued image _img_ from environment map
int width = resolution.x, height = resolution.y;
Float filter = (Float)1. / std::max(width, height);
std::unique_ptr<Float[]> img(new Float[width * height]);
for (int v = 0; v < height; ++v) {
Float vp = (Float)v / (Float)height;
Float sinTheta = std::sin(Pi * Float(v + .5f) / Float(height));
for (int u = 0; u < width; ++u) {
Float up = (Float)u / (Float)width;
img[u + v * width] = Lmap->Lookup(Point2f(up, vp), filter).y();
img[u + v * width] *= sinTheta;
}
}
// Compute sampling distributions for rows and columns of image
distribution.reset(new Distribution2D(img.get(), width, height));
}
MedianCutEnvironmentLight::MedianCutEnvironmentLight(const Transform &light2world,
const Spectrum &L, int ns_, const string &texmap)
: Light(light2world, ns_), impl(new MedCutEnvImpl {nullptr, nullptr, ns_}) {
int width = 0, height = 0;
RGBSpectrum *texels = NULL;
// Read texel data from _texmap_ into _texels_
if (texmap != "") {
texels = ReadImage(texmap, &width, &height);
if (texels)
for (int i = 0; i < width * height; ++i)
texels[i] *= L.ToRGBSpectrum();
}
if (!texels) {
width = height = 1;
texels = new RGBSpectrum[1];
texels[0] = L.ToRGBSpectrum();
}
impl->radianceMap = new MIPMap<RGBSpectrum>(width, height, texels);
impl->width = width;
impl->inv_w = 1.0f/(width-1);
impl->height = height;
impl->inv_h = 1.0f/(height-1);
impl->createDistantLight = [this](const RGBSpectrum& s, float cy, float cx) {
ParamSet p;
float rgb[3];
s.ToRGB(rgb);
p.AddRGBSpectrum("L", rgb, 3);
const float theta = impl->inv_h*cy * M_PI
, phi = impl->inv_w*cx * 2.f * M_PI;
const float costheta = cosf(theta), sintheta = sinf(theta);
const float sinphi = sinf(phi), cosphi = cosf(phi);
const Point wi(-sintheta*cosphi, -sintheta*sinphi, -costheta);
p.AddPoint(string("to"), &wi, 1);
#if DEBUG >= 1
fprintf(stderr, "rgb (%f,%f,%f)\n", rgb[0], rgb[1], rgb[2]);
#endif
return CreateDistantLight(this->LightToWorld, p);
};
impl->solid_angle = ((2.f * M_PI) / (width - 1)) * (M_PI / (1.f * (height - 1)));
#if DEBUG >= 1
fprintf(stderr, "solid_angle = %f\n", impl->solid_angle);
#endif
for (int y = 0; y < height; ++y) {
float sinTheta = sinf(M_PI * float(y + 0.5f)/height);
for (int x = 0; x < width; ++x)
texels[y*width + x] *= impl->solid_angle * sinTheta;
}
// Initialize energy sum array; the array is shifted for (1,1)
// i.e. (0,*) and (*,0) are inserted 0-boundaries
fprintf(stderr, "[+] [%10.2f] Initializing sum array\n", clock()*1.0/CLOCKS_PER_SEC);
#if DEBUG >= 3
for (int y = 0; y < 5; ++y) {
for (int x = 0; x < 5; ++x) {
fprintf(stderr, "%.2f ", texels[y*width+x].y());
}
fprintf(stderr, "\n");
}
fprintf(stderr, "\n");
#endif
vector<vector<float>> acc(height+1, vector<float>(width+1));
for (int y = 0; y < height; ++y)
for (int x = 0; x < width; ++x)
acc[y+1][x+1] = acc[y+1][x] + texels[y*width + x].y();
#if DEBUG >= 3
for (int y = 0; y < 5; ++y) {
for (int x = 0; x < 5; ++x) {
fprintf(stderr, "%.2f ", acc[y][x]);
}
fprintf(stderr, "\n");
}
fprintf(stderr, "\n");
#endif
for (int x = 1; x <= width; ++x)
for (int y = 1; y <= height; ++y)
acc[y][x] += acc[y-1][x];
#if DEBUG >= 3
for (int y = 0; y < 5; ++y) {
for (int x = 0; x < 5; ++x) {
fprintf(stderr, "%.2f ", acc[y][x]);
}
fprintf(stderr, "\n");
}
fprintf(stderr, "\n");
#endif
// initialize median cut
printf("[+] [%10.2f] Calculating median cut\n", clock()*1.0/CLOCKS_PER_SEC);
subdivide(this->impl, 1, texels, acc, 0, 0, width-1, height-1);
printf("[+] [%10.2f] Done with %d lights\n", clock()*1.0/CLOCKS_PER_SEC, static_cast<int>(impl->ls.size()));
delete[] texels;
// Initialize sampling PDFs for environment area light
// Compute scalar-valued image _img_ from environment map
float filter = 1.f / max(width, height);
float *img = new float[width*height];
for (int v = 0; v < height; ++v) {
float vp = (float)v / (float)height;
float sinTheta = sinf(M_PI * float(v+.5f)/float(height));
for (int u = 0; u < width; ++u) {
float up = (float)u / (float)width;
img[u+v*width] = impl->radianceMap->Lookup(up, vp, filter).y();
img[u+v*width] *= sinTheta;
}
}
// Compute sampling impl->distributions for rows and columns of image
impl->distribution = new Distribution2D(img, width, height);
delete[] img;
}