to match the 3D print paths view when looking at the print from the top.
GH issues #1757 #2085 #2132 #2423 #2502 #2156 #2773 #2828 #2998 #3001
The XS was left only for the unit / integration tests, and it links libslic3r only. No wxWidgets are allowed to be used from Perl starting from now.