void build(utymap::meshing::Polygon& polygon)
{
ClipperLib::ClipperOffset offset;
ClipperLib::Path path;
path.reserve(polygon.points.size() / 2);
auto lastPointIndex = polygon.points.size() - 2;
double min = std::numeric_limits<double>::max();
for (std::size_t i = 0; i < polygon.points.size(); i += 2) {
auto nextIndex = i == lastPointIndex ? 0 : i + 2;
utymap::meshing::Vector2 v1(polygon.points[i], polygon.points[i + 1]);
utymap::meshing::Vector2 v2(polygon.points[nextIndex], polygon.points[nextIndex + 1]);
min = std::min(min, utymap::meshing::Vector2::distance(v1, v2));
path.push_back(ClipperLib::IntPoint(static_cast<ClipperLib::cInt>(v1.x * Scale),
static_cast<ClipperLib::cInt>(v1.y * Scale)));
}
offset.AddPath(path, ClipperLib::JoinType::jtMiter, ClipperLib::EndType::etClosedPolygon);
ClipperLib::Paths solution;
// NOTE: use minimal side value as reference for offsetting.
offset.Execute(solution, -(min / 10) * Scale);
// NOTE: this is unexpected result for algorithm below, fallback to flat roof.
if (solution.size() != 1 || solution[0].size() != path.size()) {
return FlatRoofBuilder::build(polygon);
}
buildMansardShape(polygon, solution[0], findFirstIndex(solution[0][0], polygon));
}
static ClipperLib::Path toClipperPath(const GeometryCoordinates& ring) {
ClipperLib::Path result;
result.reserve(ring.size());
for (const auto& p : ring) {
result.emplace_back(p.x, p.y);
}
return result;
}
ClipperLib::Path
Slic3rMultiPoint_to_ClipperPath_reversed(const Slic3r::MultiPoint &input)
{
ClipperLib::Path output;
output.reserve(input.points.size());
for (Slic3r::Points::const_reverse_iterator pit = input.points.rbegin(); pit != input.points.rend(); ++pit)
output.emplace_back((*pit)(0), (*pit)(1));
return output;
}