Color World::runBiDi(vec origin, vec direction) const {
Thing *emitter = emitters[Random::upto(emitters.size())];
std::vector<Color> cumEmtWeight;
std::vector<HitInfo> emtHits;
std::vector<Color> cumEyeWeight;
std::vector<HitInfo> eyeHits;
std::vector<int> todo;
cumEmtWeight.reserve(depth);
emtHits.reserve(depth);
cumEyeWeight.reserve(depth);
eyeHits.reserve(depth);
todo.reserve(depth);
HitInfo emtInfo;
vec emtN;
vec source;
source = emitter->randomSurfacePoint(emtN);
emtInfo.hit = true;
emtInfo.incoming = emtN;
emtInfo.normal = emtN;
emtInfo.location = source;
emtInfo.mat = emitter->getMaterial();
cumEmtWeight.push_back(emitter->getMaterial()->getColor());
emtHits.push_back(emtInfo);
bool done = false;
for (int d = 1; d < depth && !done; d++) {
HitInfo newI;
newI.follow(emtHits[d-1]);
vec newDirection = emtHits[d-1].mat->sample(emtHits[d-1].incoming, emtHits[d-1].normal);
objects->hit(&newI, emtHits[d-1].location, newDirection);
cumEmtWeight.push_back(emtHits[d-1].mat->combineColor(
cumEmtWeight[d-1] * emtHits[d-1].mat->sampledPdf(
emtHits[d-1].incoming, newDirection, emtHits[d-1].normal)));
if (newI.hit)
emtHits.push_back(newI);
else
done = true;
}
HitInfo eyeInfo;
objects->hit(&eyeInfo, origin, direction);
done = false;
if (!eyeInfo.hit)
return Color(0,0,0);
cumEyeWeight.push_back(eyeInfo.mat->getColor());
eyeHits.push_back(eyeInfo);
/*for (int d = 1; d < depth && !done; d++) {
HitInfo newI;
newI.follow(eyeHits[d-1]);
vec newDirection = eyeHits[d-1].mat->sample(eyeHits[d-1].incoming, eyeHits[d-1].normal);
objects->hit(&newI, eyeHits[d-1].location, newDirection);
cumEyeWeight.push_back(eyeHits[d-1].mat->combineColor(
cumEyeWeight[d-1] * eyeHits[d-1].mat->sampledPdf(
eyeHits[d-1].incoming, newDirection, eyeHits[d-1].normal)));
if (newI.hit)
eyeHits.push_back(newI);
else
done = true;
}*/
for (int d = 1; d < depth && !todo.empty(); d++) {
HitInfo newI;
int index = todo.back();
todo.pop_back();
newI.follow(eyeHits[index]);
vec newDirection = eyeHits[index].mat->sample(eyeHits[index].incoming, eyeHits[index].normal);
objects->hit(&newI, eyeHits[index].location, newDirection);
if (newI.hit) {
Color newc = eyeHits[index].mat->combineColor(
cumEyeWeight[index] * eyeHits[index].mat->sampledPdf(
eyeHits[index].incoming, newDirection, eyeHits[index].normal));
int ints = 1;//newc.intensity() * 5 + 1;
for (int x=0; x<ints; x++)
todo.push_back(eyeHits.size());
eyeHits.push_back(newI);
cumEyeWeight.push_back(newc * (1.0/ints));
}
else
done = true;
}
Color accum;
for (int x=0; x<emtHits.size(); x++)
for (int y=0; y<eyeHits.size(); y++) {
vec dir = eyeHits[y].location - emtHits[x].location;
double dist = dir.magnitude();
dir.normalize();
HitInfo inf;
inf.distanceOnly = true;
inf.distance = dist;
objects->hit(&inf, emtHits[x].location, dir);
if (inf.distance >= dist - EPSILON || !inf.hit) {
//hit
accum += cumEyeWeight[y] * cumEmtWeight[x] *
eyeHits[y].mat->pdf(eyeHits[y].incoming, dir * -1, eyeHits[y].normal) *
emtHits[x].mat->pdf(emtHits[x].incoming, dir, emtHits[x].normal);
}
}
return accum;
/*if (eyeInfo.hit) {
vec newn;
vec dtl = eyeInfo.location - emitter->randomSurfacePoint(newn);
return emitter->getMaterial()->getColor() * eyeInfo.mat->pdf(direction*-1, dtl, eyeInfo.normal);
}
else
return Color(0,0,0);*/
}
void World::createCache() {
Thing *emitter;
HitInfo c;
int length =0;
int resetcount = 1;
HitInfo emtInfo;
vec emtN;
vec source;
emitter = emitters[Random::upto(emitters.size())];
source = emitter->randomSurfacePoint(emtN);
emtInfo.hit = true;
emtInfo.incoming = emtN;
emtInfo.normal = emtN;
emtInfo.location = source;
emtInfo.mat = emitter->getMaterial();
colorcache.push_back(emitter->getMaterial()->getColor());
hicache.push_back(emtInfo);
bool done = false;
for (int d = 1; d < cacheSize; d++) {
int i = d - 1;
double ints = colorcache[i].intensity();
if (ints < .01 || length > 60 || done) {
emitter = emitters[Random::upto(emitters.size())];
source = emitter->randomSurfacePoint(emtN);
emtInfo.distance = 0;
emtInfo.previousDistances = 0;
emtInfo.hit = true;
emtInfo.incoming = emtN;
emtInfo.normal = emtN;
emtInfo.location = source;
emtInfo.mat = emitter->getMaterial();
int intes = 1;//emitter->getMaterial()->getColor().intensity() + 1;
for (int x=0; x<intes; x++) {
colorcache.push_back(emitter->getMaterial()->getColor() * (1.0/intes));
hicache.push_back(emtInfo);
}
resetcount++;
d += intes-1;
done = false;
length = 0;
continue;
}
length++;
HitInfo newI;
newI.follow(hicache[d-1]);
vec newDirection = hicache[d-1].mat->sample(hicache[d-1].incoming, hicache[d-1].normal);
objects->hit(&newI, hicache[d-1].location, newDirection);
if (newI.hit) {
Color newc = hicache[d-1].mat->combineColor(colorcache[d-1] *
hicache[d-1].mat->sampledPdf(hicache[d-1].incoming, newDirection, hicache[d-1].normal));
int intes = 1;//newc.intensity()*3 + 1;
for (int x=0; x<intes; x++) {
hicache.push_back(newI);
colorcache.push_back(newc * (1.0/intes));
}
d += intes-1;
}
else {
done = true;
d--;
}
}
cacheweight = (cacheSize * 1.0 / resetcount);
}
