Closed alranel closed 12 years ago
Straight skeleton- track all skeleton segments that emanate from split and polygon collapse events.
See http://farm6.static.flickr.com/5009/5367603854_debc713f34.jpg from http://twak.blogspot.com/2011/01/degeneracy-in-weighted-straight.html for example
Model: https://idisk.mac.com/raldrich//Public/Reprap/raldrich_x-struder.stl
Slice with Slic3r 0-5-2, with default settings.
In layers 11-14, support structures are missing from the belt clamps - most likely because the features are too thin for Slic3r to render.
At the very least, it would be nice if Slic3r displayed the minimum supported feature size for a given extrusion width.
(By the way, the bridge issues in that model seem to be resolved.)
Another test case -- The "bird nose" here: http://www.thingiverse.com/thing:13628 also has supports that fail to render.
Thank you, we don't need anymore test cases :) The problem is well defined.
I explained the problem here: https://github.com/alexrj/Slic3r/wiki/Skeletonization
Definition: a thin wall is a part of your model whose thickness in the XY plane is <= extrusion width.
Slic3r currently ignores them and produces no extrusion. This is because it tries to draw an outline for the part (that is, 2*extrusion width). We need an algorithm to detect these parts and one to generate a single-path extrusion for them
Detection of thin-walls: inset polygons, then outset them again, and do the difference between the original ones and the result; what's missing are thin walls.
Now the question is: given a thin polygon (with variable thickness and direction), how can we detect its backbone?