void polish_intersections(std::vector<std::pair<double, double> > &xs,
D2<SBasis> const &A, D2<SBasis> const &B)
{
for(unsigned i = 0; i < xs.size(); i++)
intersect_polish_root(A, xs[i].first,
B, xs[i].second);
}
/**
* This uses the local bounds functions of curves to generically intersect two.
* It passes in the curves, time intervals, and keeps track of depth, while
* returning the results through the Crossings parameter.
*/
void pair_intersect(Curve const & A, double Al, double Ah,
Curve const & B, double Bl, double Bh,
Crossings &ret, unsigned depth=0) {
// std::cout << depth << "(" << Al << ", " << Ah << ")\n";
OptRect Ar = A.boundsLocal(Interval(Al, Ah));
if (!Ar) return;
OptRect Br = B.boundsLocal(Interval(Bl, Bh));
if (!Br) return;
if(! Ar->intersects(*Br)) return;
//Checks the general linearity of the function
if((depth > 12)) { // || (A.boundsLocal(Interval(Al, Ah), 1).maxExtent() < 0.1
//&& B.boundsLocal(Interval(Bl, Bh), 1).maxExtent() < 0.1)) {
double tA, tB, c;
if(linear_intersect(A.pointAt(Al), A.pointAt(Ah),
B.pointAt(Bl), B.pointAt(Bh),
tA, tB, c)) {
tA = tA * (Ah - Al) + Al;
tB = tB * (Bh - Bl) + Bl;
intersect_polish_root(A, tA,
B, tB);
if(depth % 2)
ret.push_back(Crossing(tB, tA, c < 0));
else
ret.push_back(Crossing(tA, tB, c > 0));
return;
}
}
if(depth > 12) return;
double mid = (Bl + Bh)/2;
pair_intersect(B, Bl, mid,
A, Al, Ah,
ret, depth+1);
pair_intersect(B, mid, Bh,
A, Al, Ah,
ret, depth+1);
}
//same as below but curves not paths
void mono_intersect(Curve const &A, double Al, double Ah,
Curve const &B, double Bl, double Bh,
Crossings &ret, double tol = 0.1, unsigned depth = 0) {
if( Al >= Ah || Bl >= Bh) return;
//std::cout << " " << depth << "[" << Al << ", " << Ah << "]" << "[" << Bl << ", " << Bh << "]";
Point A0 = A.pointAt(Al), A1 = A.pointAt(Ah),
B0 = B.pointAt(Bl), B1 = B.pointAt(Bh);
//inline code that this implies? (without rect/interval construction)
Rect Ar = Rect(A0, A1), Br = Rect(B0, B1);
if(!Ar.intersects(Br) || A0 == A1 || B0 == B1) return;
if(depth > 12 || (Ar.maxExtent() < tol && Ar.maxExtent() < tol)) {
double tA, tB, c;
if(linear_intersect(A.pointAt(Al), A.pointAt(Ah),
B.pointAt(Bl), B.pointAt(Bh),
tA, tB, c)) {
tA = tA * (Ah - Al) + Al;
tB = tB * (Bh - Bl) + Bl;
intersect_polish_root(A, tA,
B, tB);
if(depth % 2)
ret.push_back(Crossing(tB, tA, c < 0));
else
ret.push_back(Crossing(tA, tB, c > 0));
return;
}
}
if(depth > 12) return;
double mid = (Bl + Bh)/2;
mono_intersect(B, Bl, mid,
A, Al, Ah,
ret, tol, depth+1);
mono_intersect(B, mid, Bh,
A, Al, Ah,
ret, tol, depth+1);
}
