Use Slic3r::Geometry polyline_lines rather than duplicate implementation.
Use Slic3r::Geometry polyline_lines rather than duplicate implementation.

If it is good enough for polygons, it should be good enough for polylines.

tmotl/Slic3r,xoan/Slic3r,platsch/Slic3r,pieis2pi/Slic3r,tmotl/Slic3r,platsch/Slic3r,mcilhargey/Slic3r,lordofhyphens/Slic3r,mcilhargey/Slic3r,prusa3d/Slic3r,mcilhargey/Slic3r,alexrj/Slic3r,pieis2pi/Slic3r,curieos/Slic3r,prusa3d/Slic3r,platsch/Slic3r,xoan/Slic3r,mcilhargey/Slic3r,mcilhargey/Slic3r,alexrj/Slic3r,tmotl/Slic3r,platsch/Slic3r,platsch/Slic3r,lordofhyphens/Slic3r,pieis2pi/Slic3r,curieos/Slic3r,pieis2pi/Slic3r,platsch/Slic3r,tmotl/Slic3r,xoan/Slic3r,prusa3d/Slic3r,tmotl/Slic3r,xoan/Slic3r,prusa3d/Slic3r,curieos/Slic3r,alexrj/Slic3r,lordofhyphens/Slic3r,prusa3d/Slic3r,mcilhargey/Slic3r,prusa3d/Slic3r,curieos/Slic3r,pieis2pi/Slic3r,mcilhargey/Slic3r,prusa3d/Slic3r,lordofhyphens/Slic3r,pieis2pi/Slic3r,alexrj/Slic3r,alexrj/Slic3r,tmotl/Slic3r,xoan/Slic3r,lordofhyphens/Slic3r,xoan/Slic3r,curieos/Slic3r,curieos/Slic3r,lordofhyphens/Slic3r,alexrj/Slic3r