cv::Vec3f AreaLight::getIntensity(const HitRecord & hit, QVector3D &direction, const Intersectable &scene, const Sample &sample) const
{
QVector3D at = hit.getIntersectingPoint().toVector3DAffine();
QPointF p = sample.getSample();
QVector3D lightLocation = getLocation(p);
direction = at - lightLocation;
HitRecord shadowHit = scene.intersect(Ray(at, -direction.normalized(), EPSILON, direction.length() - EPSILON));
if(shadowHit.intersects() && &shadowHit.getMaterial() != this)
{
return cv::Vec3f();
}
else
{
return getIntensity(direction);
}
}
Path Renderer::createPath(const Ray& primaryRay, const Intersectable &scene, const Sample pathSamples[], cv::Vec3f alpha, int pathLength, float russianRoulettePdf, int russianRouletteStartIndex)
{
Path result;
HitRecord hit = scene.intersect(primaryRay);
for(int i = 0; i < pathLength; i++)
{
if(!hit.intersects()) return result;
float pdf;
cv::Vec3f brdf;
QVector3D outDirection = hit.getMaterial().outDirection(hit, pathSamples[i], pdf, brdf);
if(hit.getMaterial().emitsLight())
{
result.alphaValues.push_back(alpha);
result.hitRecords.push_back(hit);
return result;
}
else if(hit.getMaterial().isSpecular())
{
//Try not to terminate on refractive vertices
if(i == pathLength - 1 && pathLength < MAX_DEPTH) pathLength++;
}
else
{
result.alphaValues.push_back(alpha);
result.hitRecords.push_back(hit);
if(pdf == 0 || alpha == cv::Vec3f()) return result;
float cos = fabs(QVector3D::dotProduct(outDirection.normalized(), hit.getSurfaceNormal().normalized()));
assert(cos >= 0 && !isnan(pdf));
assert(pdf > 0 && !isnan(pdf));
alpha = alpha.mul(brdf) * (cos / pdf);
if(i > russianRouletteStartIndex) alpha *= (1 / russianRoulettePdf);
}
hit = scene.intersect(Ray(hit.getIntersectingPoint(), outDirection));
}
return result;
}
