void NavigationPolygon::make_polygons_from_outlines() {
List<TriangulatorPoly> in_poly,out_poly;
Vector2 outside_point(-1e10,-1e10);
for(int i=0; i<outlines.size(); i++) {
DVector<Vector2> ol = outlines[i];
int olsize = ol.size();
if (olsize<3)
continue;
DVector<Vector2>::Read r=ol.read();
for(int j=0; j<olsize; j++) {
outside_point.x = MAX( r[j].x, outside_point.x );
outside_point.y = MAX( r[j].y, outside_point.y );
}
}
outside_point+=Vector2(0.7239784,0.819238); //avoid precision issues
for(int i=0; i<outlines.size(); i++) {
DVector<Vector2> ol = outlines[i];
int olsize = ol.size();
if (olsize<3)
continue;
DVector<Vector2>::Read r=ol.read();
int interscount=0;
//test if this is an outer outline
for(int k=0; k<outlines.size(); k++) {
if (i==k)
continue; //no self intersect
DVector<Vector2> ol2 = outlines[k];
int olsize2 = ol2.size();
if (olsize2<3)
continue;
DVector<Vector2>::Read r2=ol2.read();
for(int l=0; l<olsize2; l++) {
if (Geometry::segment_intersects_segment_2d(r[0],outside_point,r2[l],r2[(l+1)%olsize2],NULL)) {
interscount++;
}
}
}
bool outer = (interscount%2)==0;
TriangulatorPoly tp;
tp.Init(olsize);
for(int j=0; j<olsize; j++) {
tp[j]=r[j];
}
if (outer)
tp.SetOrientation(TRIANGULATOR_CCW);
else {
tp.SetOrientation(TRIANGULATOR_CW);
tp.SetHole(true);
}
in_poly.push_back(tp);
}
TriangulatorPartition tpart;
if (tpart.ConvexPartition_HM(&in_poly,&out_poly)==0) { //failed!
print_line("convex partition failed!");
return;
}
polygons.clear();
vertices.resize(0);
Map<Vector2,int> points;
for(List<TriangulatorPoly>::Element*I = out_poly.front(); I; I=I->next()) {
TriangulatorPoly& tp = I->get();
struct Polygon p;
for(int i=0; i<tp.GetNumPoints(); i++) {
Map<Vector2,int>::Element *E=points.find(tp[i]);
if (!E) {
E=points.insert(tp[i],vertices.size());
vertices.push_back(tp[i]);
}
p.indices.push_back(E->get());
}
polygons.push_back(p);
}
emit_signal(CoreStringNames::get_singleton()->changed);
}
