void divide_and_conquer(const pointVec_t &P, pointVec_t &H,
point_t p1, point_t p2, bool buffered) {
assert(P.size() >= 2);
pointVec_t P_reduced;
pointVec_t H1, H2;
point_t p_far;
if(buffered) {
p_far = divide<SplitByCP_buf>(P, P_reduced, p1, p2);
} else {
p_far = divide<SplitByCP>(P, P_reduced, p1, p2);
}
if (P_reduced.size()<2) {
H.push_back(p1);
#if USECONCVEC
appendVector(P_reduced, H);
#else // insert into STD::VECTOR
H.insert(H.end(), P_reduced.begin(), P_reduced.end());
#endif
}
else {
divide_and_conquer(P_reduced, H1, p1, p_far, buffered);
divide_and_conquer(P_reduced, H2, p_far, p2, buffered);
#if USECONCVEC
appendVector(H1, H);
appendVector(H2, H);
#else // insert into STD::VECTOR
H.insert(H.end(), H1.begin(), H1.end());
H.insert(H.end(), H2.begin(), H2.end());
#endif
}
}
void quickhull(const pointVec_t &points, pointVec_t &hull) {
if (points.size() < 2) {
hull.insert(hull.end(), points.begin(), points.end());
return;
}
point_t p_maxx = extremum<FindXExtremum::maxX>(points);
point_t p_minx = extremum<FindXExtremum::minX>(points);
pointVec_t H;
divide_and_conquer(points, hull, p_maxx, p_minx);
divide_and_conquer(points, H, p_minx, p_maxx);
hull.insert(hull.end(), H.begin(), H.end());
}
void divide_and_conquer(const pointVec_t &P, pointVec_t &H, point_t p1, point_t p2) {
assert(P.size() >= 2);
pointVec_t P_reduced;
pointVec_t H1, H2;
point_t p_far = divide(P, P_reduced, p1, p2);
if (P_reduced.size()<2) {
H.push_back(p1);
H.insert(H.end(), P_reduced.begin(), P_reduced.end());
}
else {
divide_and_conquer(P_reduced, H1, p1, p_far);
divide_and_conquer(P_reduced, H2, p_far, p2);
H.insert(H.end(), H1.begin(), H1.end());
H.insert(H.end(), H2.begin(), H2.end());
}
}
void quickhull(const pointVec_t &points, pointVec_t &hull, bool buffered) {
if (points.size() < 2) {
#if USECONCVEC
appendVector(points, hull);
#else // STD::VECTOR
hull.insert(hull.end(), points.begin(), points.end());
#endif // USECONCVEC
return;
}
point_t p_maxx = extremum<FindXExtremum::maxX>(points);
point_t p_minx = extremum<FindXExtremum::minX>(points);
pointVec_t H;
divide_and_conquer(points, hull, p_maxx, p_minx, buffered);
divide_and_conquer(points, H, p_minx, p_maxx, buffered);
#if USECONCVEC
appendVector(H, hull);
#else // STD::VECTOR
hull.insert(hull.end(), H.begin(), H.end());
#endif // USECONCVEC
}
point_t divide(const pointVec_t &P, pointVec_t &P_reduced, const point_t &p1, const point_t &p2) {
SplitByCP splitByCP(p1, p2, P_reduced);
point_t farPoint = std::for_each(P.begin(), P.end(), splitByCP);
if(util::verbose) {
std::stringstream ss;
ss << P.size() << " nodes in bucket"<< ", "
<< "dividing by: [ " << p1 << ", " << p2 << " ], "
<< "farthest node: " << farPoint;
util::OUTPUT.push_back(ss.str());
}
return farPoint;
}
void appendVector(const pointVec_t& src, pointVec_t& dest) {
std::copy(src.begin(), src.end(), dest.grow_by(src.size()));
}
point_t extremum(const pointVec_t &points) {
assert(!points.empty());
return std::for_each(points.begin(), points.end(), FindXExtremum(points[0], type));
}
void appendVector(mutex_t& insertMutex, const point_t* src, size_t srcSize,
pointVec_t& dest) {
mutex_t::scoped_lock lock(insertMutex);
dest.insert(dest.end(), src, src + srcSize);
}
void appendVector(mutex_t& insertMutex, const pointVec_t& src, pointVec_t& dest) {
mutex_t::scoped_lock lock(insertMutex);
dest.insert(dest.end(), src.begin(), src.end());
}