diff options
| -rw-r--r-- | svg-flatten/src/svg_geom.cpp | 70 |
1 files changed, 64 insertions, 6 deletions
diff --git a/svg-flatten/src/svg_geom.cpp b/svg-flatten/src/svg_geom.cpp index 3825775..da9d78d 100644 --- a/svg-flatten/src/svg_geom.cpp +++ b/svg-flatten/src/svg_geom.cpp @@ -91,6 +91,64 @@ enum ClipperLib::JoinType gerbolyze::clipper_join_type(const pugi::xml_node &nod return ClipperLib::jtMiter; } +/* Some debugging helpers */ +static double toplevel_winding_direction(PolyNode &ptree) { + double sum = 0.0; + size_t sz = ptree.Contour.size(); + for (size_t i=0; i<sz; i++) { + size_t j = (i+1) % sz; + double x1 = ptree.Contour[i].X, y1 = ptree.Contour[i].Y; + double x2 = ptree.Contour[j].X, y2 = ptree.Contour[j].Y; + sum += (x2-x1)*(y2+y1); + } + return sum; +} + +static void dump_ptree(PolyNode &ptree) { + /* dumps node count, winding direction and tree structure */ + double sum = toplevel_winding_direction(ptree); + char sign = '.'; + if (sum > 0) { + sign = '+'; + } else if (sum < 0) { + sign = '-'; + } + + cerr << sign << ptree.Contour.size() << "["; + for (size_t i=0; i<ptree.ChildCount(); i++) { + if (i > 0) { + cerr << ","; + } + dump_ptree(*ptree.Childs[i]); + } + cerr << "]"; +} + +static void dump_clipper2svg(Path &path, string stroke) { + /* dumps the ptree to SVG */ + /* use together with + cerr << "<svg width=\"200\" height=\"200\" xmlns=\"http://www.w3.org/2000/svg\">" << endl; + ... + dump_clipper2svg(...); // can be used multiple times + ... + cerr << "</svg>" << endl; + */ + + size_t sz = path.size(); + if (sz == 0) { + return; + } + + cerr << "<path fill=\"" << stroke << "\" d=\"M "; + for (size_t i=0; i<sz; i++) { + if (i>0) { + cerr << " L "; + } + cerr << (path[i].X / 1e7) << ", " << (path[i].Y / 1e7); + } + cerr << " Z\"/>" << endl; +} + static void dehole_polytree_worker(PolyNode &ptree, Paths &out, queue<PolyTree> &todo) { for (int i=0; i<ptree.ChildCount(); i++) { PolyNode *nod = ptree.Childs[i]; @@ -127,21 +185,21 @@ static void dehole_polytree_worker(PolyNode &ptree, Paths &out, queue<PolyTree> * until we find a point that has a different X coordinate than our starting point. If we can't find one * because the polygon only consists only of points on a vertical line, we can safely discard it and do * nothing since it has zero area anyway. */ - for (size_t i=0; i<nod->Childs[0]->Contour.size(); i++) { - if (nod->Childs[0]->Contour[i].X == nod->Childs[0]->Contour[0].X) { + for (size_t i=1; i<nod->Childs[0]->Contour.size(); i++) { + if (nod->Childs[0]->Contour[i].X == nod->Childs[0]->Contour[i-1].X) { continue; } - /* We now have found that Contour[0] - Contour[i] has a non-zero horizontal component, and is a + /* We now have found that Contour[i-1] - Contour[i] has a non-zero horizontal component, and is a * candidate for our cut. However, we have to make sure that the first point is left (lower X * coordinate) of the second point, or the cutting polygon we create here would have a * self-intersection, which with high likelihood would lead to a new hole being created when cutting. */ - int a=0, b=i; - if (nod->Childs[0]->Contour[i].X < nod->Childs[0]->Contour[0].X) { + int a=i-1, b=i; + if (nod->Childs[0]->Contour[i].X < nod->Childs[0]->Contour[i-1].X) { /* Swap points */ a = i; - b = 0; + b = i-1; } Path tri = { { bbox.left, bbox.top }, nod->Childs[0]->Contour[a], nod->Childs[0]->Contour[b], { bbox.right, bbox.top } }; c.AddPath(tri, ptClip, true); |