bool Polygon::containsSegment(GeoLib::LineSegment const& segment) const
{
std::vector<GeoLib::Point> s(getAllIntersectionPoints(segment));
GeoLib::Point const& a {
segment.getBeginPoint()
};
GeoLib::Point const& b {
segment.getEndPoint()
};
// no intersections -> check if at least one point of segment is in polygon
if (s.empty()) {
return (isPntInPolygon(a));
}
const double tol(std::numeric_limits<float>::epsilon());
// one intersection, intersection in line segment end point
if (s.size() == 1) {
const double sqr_dist_as(MathLib::sqrDist(a,s[0]));
if (sqr_dist_as < tol) {
return (isPntInPolygon(b));
}
const double sqr_dist_bs(MathLib::sqrDist(b,s[0]));
if (sqr_dist_bs < tol) {
return (isPntInPolygon(a));
}
}
// Sorting the intersection with respect to the distance to the point a.
// This induces a partition of the line segment into sub segments.
std::sort(s.begin(), s.end(),
[&a] (GeoLib::Point const& p0, GeoLib::Point const& p1) {
return MathLib::sqrDist(a, p0) < MathLib::sqrDist(a, p1);
}
);
// remove sub segments with almost zero length
for (std::size_t k(0); k<s.size()-1; ) {
if (MathLib::sqrDist(s[k], s[k+1]) < tol) {
s.erase(s.begin()+k+1);
} else {
k++;
}
}
// Check if all sub segments are within the polygon.
if (!isPntInPolygon(GeoLib::Point(0.5*(a[0]+s[0][0]), 0.5*(a[1]+s[0][1]), 0.5*(a[2]+s[0][2]))))
return false;
const std::size_t n_sub_segs(s.size()-1);
for (std::size_t k(0); k<n_sub_segs; k++) {
if (!isPntInPolygon(GeoLib::Point(0.5*(s[k][0]+s[k+1][0]), 0.5*(s[k][1]+s[k+1][1]), 0.5*(s[k][2]+s[k+1][2]))))
return false;
}
if (!isPntInPolygon(GeoLib::Point(0.5*(s[0][0]+b[0]), 0.5*(s[0][1]+b[1]), 0.5*(s[0][2]+b[2]))))
return false;
return true;
}
bool Polygon::isPartOfPolylineInPolygon(const Polyline& ply) const
{
const std::size_t ply_size (ply.getNumberOfPoints());
// check points
for (std::size_t k(0); k < ply_size; k++) {
if (isPntInPolygon (*(ply.getPoint(k)))) {
return true;
}
}
GeoLib::Point s;
for (auto polygon_seg : *this) {
for (auto polyline_seg : ply) {
if (GeoLib::lineSegmentIntersect(polyline_seg, polygon_seg, s)) {
return true;
}
}
}
return false;
}
bool Polygon::isPntInPolygon(double x, double y, double z) const
{
const GeoLib::Point pnt(x,y,z);
return isPntInPolygon (pnt);
}
