Butterfly subdivision produces faces with nils about geom

[postspectacular]

Butterfly subdivision principally only works with triangle meshes. so please tessellate first - i know, i know... documentation should mention this! :)

Original paper: http://www.math.tau.ac.il/~niradyn/papers/butterfly.pdf

[postspectacular]

(def m (-> (c/cuboid 80) (g/as-mesh {:mesh (gm/gmesh)})))
(def m2 (last (take 6 (iterate sd/butterfly (g/tessellate m)))))
(with-open [o (io/output-stream "foo.ply")] (mio/write-ply (mio/wrapped-output-stream o) m2))

[postspectacular]

Proposed fix: Add docstring to point out triangle / pre-tessellation requirement

[jackrusher]

Ah, of course! Thanks for the paper.

[postspectacular]

Closing this, since it's actually already mentioned :) https://github.com/thi-ng/geom/blob/master/geom-meshops/src/subdivision.org#butterfly