GitHub-Proxy/Slic3r
1
0
Fork 0
mirror of https://git.mirrors.martin98.com/https://github.com/slic3r/Slic3r.git synced 2025-07-24 05:04:25 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fix a clipper bug when a line in a polyline is horizontal.

Browse Source 
Have to do a hack to prevent horizontal lines.
If someone can modify clipper to take into account this corner case,
please submit a fix. But maybe it's better to go to clipper2 directly.
Note: I tested with clipper 6.4.2, but it doesn't fix this bug.
supermerill/SuperSlicer#1624
This commit is contained in:
supermerill 2021-10-10 01:14:32 +02:00
parent 812dfdb484
commit 37838be7cf
1 changed files with 32 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
src/libslic3r/ClipperUtils.cpp
View File

@ -598,7 +598,21 @@ ClipperLib::PolyTree _clipper_do_pl(const ClipperLib::ClipType clipType, const P
// read input
ClipperLib::Paths input_subject = Slic3rMultiPoints_to_ClipperPaths(subject);
ClipperLib::Paths input_clip = Slic3rMultiPoints_to_ClipperPaths(clip);
//perform y safing : if a line is on the same Y, clipper may not pick the good point.
std::set<coord_t> bad_y;
for (ClipperLib::Paths* input : {&input_subject, &input_clip} )
for (ClipperLib::Path& path : *input) {
coord_t lasty = 0;
for (ClipperLib::IntPoint& pt : path) {
if (lasty == pt.Y) {
pt.Y+=1;
bad_y.insert(pt.Y);
}
lasty = pt.Y;
}
}
// perform safety offset
if (safety_offset_) safety_offset(&input_clip);
@ -613,6 +627,23 @@ ClipperLib::PolyTree _clipper_do_pl(const ClipperLib::ClipType clipType, const P
// perform operation
ClipperLib::PolyTree retval;
clipper.Execute(clipType, retval, fillType, fillType);
//restore good y
if (!bad_y.empty()) {
std::vector<ClipperLib::PolyNode*> to_check;
to_check.push_back(&retval);
while (!to_check.empty()) {
ClipperLib::PolyNode* node = to_check.back();
to_check.pop_back();
for (ClipperLib::IntPoint& pt : node->Contour) {
if (bad_y.find(pt.Y) != bad_y.end()) {
pt.Y-=1;
}
}
to_check.insert(to_check.end(), node->Childs.begin(), node->Childs.end());
}
}
return retval;
}