void simplify_polygons(const Slic3r::Polygons &subject, Slic3r::ExPolygons* retval, bool preserve_collinear)
{
PROFILE_FUNC();
if (!preserve_collinear) {
Polygons polygons;
simplify_polygons(subject, &polygons, preserve_collinear);
union_(polygons, retval);
return;
}
// convert into Clipper polygons
ClipperLib::Paths input_subject;
Slic3rMultiPoints_to_ClipperPaths(subject, &input_subject);
ClipperLib::PolyTree polytree;
ClipperLib::Clipper c;
c.PreserveCollinear(true);
c.StrictlySimple(true);
c.AddPaths(input_subject, ClipperLib::ptSubject, true);
c.Execute(ClipperLib::ctUnion, polytree, ClipperLib::pftNonZero, ClipperLib::pftNonZero);
// convert into ExPolygons
PolyTreeToExPolygons(polytree, retval);
}
Polygons
Polygon::simplify(double tolerance) const
{
Polygon p = *this;
p.points = MultiPoint::_douglas_peucker(p.points, tolerance);
Polygons pp;
pp.push_back(p);
simplify_polygons(pp, pp);
return pp;
}
// this only works on CCW polygons as CW will be ripped out by Clipper's simplify_polygons()
Polygons
Polygon::simplify(double tolerance) const
{
// repeat first point at the end in order to apply Douglas-Peucker
// on the whole polygon
Points points = this->points;
points.push_back(points.front());
Polygon p(MultiPoint::_douglas_peucker(points, tolerance));
p.points.pop_back();
Polygons pp;
pp.push_back(p);
simplify_polygons(pp, &pp);
return pp;
}
ExPolygons simplify_polygons_ex(const Polygons &subject, bool preserve_collinear)
{
if (! preserve_collinear)
return union_ex(simplify_polygons(subject, false));
// convert into Clipper polygons
ClipperLib::Paths input_subject = Slic3rMultiPoints_to_ClipperPaths(subject);
ClipperLib::PolyTree polytree;
ClipperLib::Clipper c;
c.PreserveCollinear(true);
c.StrictlySimple(true);
c.AddPaths(input_subject, ClipperLib::ptSubject, true);
c.Execute(ClipperLib::ctUnion, polytree, ClipperLib::pftNonZero, ClipperLib::pftNonZero);
// convert into ExPolygons
return PolyTreeToExPolygons(polytree);
}
