void test02_roughTransmittance() {
RoughTransmittance rtr(MicrofacetDistribution::EBeckmann);
ref<Random> random = new Random();
for (int i=0; i<50; ++i) {
Float alpha = std::pow(random->nextFloat(), (Float) 4.0f)*4;
Float eta = 1 + std::pow(random->nextFloat(), (Float) 4.0f)*3;
if (alpha < 1e-5)
alpha = 1e-5f;
if (eta < 1+1e-5)
eta = 1+1e-5f;
//eta = 1/eta;
Float refD = computeDiffuseTransmittance("beckmann", eta, alpha);
Float datD = rtr.evalDiffuse(alpha, eta);
cout << "Testing " << i << "/50" << endl;
if (std::abs(refD-datD) > 1e-3f) {
cout << endl;
cout << "eta = " << eta << endl;
cout << "alpha = " << alpha << endl;
cout << "diff=" << datD-refD << " (datD=" << datD << ", ref=" << refD << ")" << endl;
}
}
Float avgErr = 0.0f;
for (int i=0; i<1000; ++i) {
Float cosTheta = random->nextFloat();
Float alpha = std::pow(random->nextFloat(), (Float) 4.0f)*4;
Float eta = 1 + std::pow(random->nextFloat(), (Float) 4.0f)*3;
if (cosTheta < 1e-5)
cosTheta = 1e-5f;
if (alpha < 1e-5)
alpha = 1e-5f;
if (eta < 1+1e-5)
eta = 1+1e-5f;
//eta = 1/eta;
Float ref = computeTransmittance("beckmann", eta, alpha, cosTheta);
Float dat = rtr.eval(cosTheta, alpha, eta);
if (i % 20 == 0)
cout << "Testing " << i << "/1000" << endl;
if (std::abs(ref-dat) > 1e-3f) {
cout << endl;
cout << "eta = " << eta << endl;
cout << "alpha = " << alpha << endl;
cout << "cosTheta = " << cosTheta << endl;
cout << "diff=" << dat-ref << " (dat=" << dat << ", ref=" << ref << ")" << endl;
}
avgErr += ref-dat;
}
avgErr /= 1000;
cout << "Avg error = " << avgErr << endl;
}
void test04_roughTransmittanceFixedEtaFixedAlpha() {
ref<Timer> timer = new Timer();
RoughTransmittance rtr(MicrofacetDistribution::EBeckmann);
Float eta = 1.5f;
Float alpha = 0.2f;
rtr.setEta(eta);
rtr.setAlpha(alpha);
cout << "Loading and projecting took " << timer->getMilliseconds() << " ms" << endl;
ref<Random> random = new Random();
Float refD = computeDiffuseTransmittance("beckmann", eta, alpha);
Float datD = rtr.evalDiffuse(alpha, eta);
if (std::abs(refD-datD) > 1e-3f) {
cout << endl;
cout << "alpha = " << alpha << endl;
cout << "diff=" << datD-refD << " (datD=" << datD << ", ref=" << refD << ")" << endl;
}
Float avgErr = 0.0f;
for (int i=0; i<1000; ++i) {
Float cosTheta = random->nextFloat();
if (cosTheta < 1e-5)
cosTheta = 1e-5f;
Float ref = computeTransmittance("beckmann", eta, alpha, cosTheta);
Float dat = rtr.eval(cosTheta, alpha, eta);
if (i % 20 == 0)
cout << "Testing " << i << "/1000" << endl;
if (std::abs(ref-dat) > 1e-3f) {
cout << endl;
cout << "eta = " << eta << endl;
cout << "alpha = " << alpha << endl;
cout << "cosTheta = " << cosTheta << endl;
cout << "diff=" << dat-ref << " (dat=" << dat << ", ref=" << ref << ")" << endl;
}
avgErr += ref-dat;
}
avgErr /= 1000;
cout << "Avg error = " << avgErr << endl;
}
void fit(const char *name, int inverted) {
size_t resolutionIOR = RESOLUTION_IOR,
resolutionAlpha = RESOLUTION_ROUGHNESS,
resolutionTheta = RESOLUTION_THETA;
Float alphaStart = ROUGHNESS_START,
alphaEnd = ROUGHNESS_END,
iorStart = IOR_START,
iorEnd = IOR_END;
std::ofstream os(formatString("%s%i.m", name, inverted).c_str());
os << std::fixed << std::setprecision(8);
os << "alphaStart=" << alphaStart << ";" << endl;
os << "alphaEnd=" << alphaEnd << ";" << endl;
os << "iorStart=" << iorStart << ";" << endl;
os << "iorEnd=" << iorEnd << ";" << endl;
os << "alphaSteps=" << resolutionAlpha << ";" << endl;
os << "thetaSteps=" << resolutionTheta << ";" << endl;
os << "iorSteps=" << resolutionIOR << ";" << endl;
os << "transmittance={" << endl;
ref<FileStream> fstream = new FileStream(formatString("data/microfacet/%s.dat", name).c_str(),
inverted ? FileStream::EAppendReadWrite : FileStream::ETruncReadWrite);
fstream->setByteOrder(Stream::ELittleEndian);
if (!inverted) {
fstream->write("MTS_TRANSMITTANCE", 17);
fstream->writeSize(resolutionIOR);
fstream->writeSize(resolutionAlpha);
fstream->writeSize(resolutionTheta);
fstream->writeSingle(iorStart);
fstream->writeSingle(iorEnd);
fstream->writeSingle(alphaStart);
fstream->writeSingle(alphaEnd);
}
Float iorStepSize = 1.0f / (resolutionIOR-1),
alphaStepSize = 1.0f / (resolutionAlpha-1);
for (size_t i=0; i<resolutionIOR; ++i) {
Float t = i * iorStepSize;
Float ior = iorStart + (iorEnd-iorStart) * std::pow(t, (Float) 4.0f);
cout << "ior = " << ior << endl;
os << "\t{" << endl;
for (size_t j=0; j<resolutionAlpha; ++j) {
Float t = j * alphaStepSize;
Float alpha = alphaStart + (alphaEnd-alphaStart) * std::pow(t, (Float) 4.0f);
cout << "alpha = " << alpha << endl;
Float diffTrans;
Float *transmittance = computeTransmittance(name,
ior, alpha, resolutionTheta, diffTrans, inverted);
os << "\t\t{";
for (size_t k=0; k<resolutionTheta; ++k) {
fstream->writeSingle((float) transmittance[k]);
os << transmittance[k];
if (k+1 < resolutionTheta)
os << ", ";
}
os << "}";
if (j + 1 < resolutionAlpha)
os << ",";
os << endl;
delete[] transmittance;
fstream->writeSingle((float) diffTrans);
}
os << "\t}";
if (i + 1 < resolutionIOR)
os << ",";
os << endl;
cout << endl;
}
os << "};" << endl;
os.close();
fstream->close();
}
