Crash in Project() about manifold

[kintel]

I haven't tried, but it's worth a try. Nevertheless, it wouldn't hurt adding a test for Project(), to make it easier to test things like this without doing it via OpenSCAD.

[kintel]

OpenSCAD crashes on projection() import("file.obj") with this OBJ file.
projection() in OpenSCAD currently just calls Manifold::Project()

Note: This is slimmed down from the GEB example in OpenSCAD: https://github.com/openscad/openscad/blob/master/examples/Advanced/GEB.scad

# OpenSCAD obj exporter
v -2 -0.7 -0.1
v -2 -0.7 0
v -1.9 -0.7 -0.1
v -1.9 -0.6901 -0.1
v -1.9 -0.7 0
v -1.9 -0.6901 0
v -2 -1 3
v -1.9 -1 3
v -2 -1 4
v -1.9 -1 4
v -1.9 -0.6901 3
v -1.9 -0.6901 4
v -1.7 -0.6901 3
v -1.7 -0.6901 3.2
v -2 0 -0.1
v -2 0 0
v -2 0 3
v -2 0 4
v -1.7 0 3
v -1.7 0 3.2
v -1 -0.6901 -0.1
v -1 -0.6901 0
v -1 -0.6901 3.2
v -1 -0.6901 4
v -1 0 -0.1
v -1 0 0
v -1 0 3.2
v -1 0 4
f  1 3 2
f  1 4 3
f  2 3 5
f  5 6 2
f  3 4 6
f  5 3 6
f  6 4 21
f  26 22 25
f  21 25 22
f  25 15 26
f  26 6 22
f  21 4 25
f  21 22 6
f  16 26 15
f  16 6 26
f  4 15 25
f  15 1 16
f  16 2 6
f  4 1 15
f  1 2 16
f  12 14 23
f  12 13 14
f  12 11 13
f  18 9 12
f  11 7 17
f  7 9 18
f  17 7 18
f  13 11 19
f  17 18 20
f  19 11 17
f  19 17 20
f  14 13 20
f  18 12 24
f  20 13 19
f  20 18 27
f  12 10 11
f  24 12 23
f  9 10 12
f  9 8 10
f  8 11 10
f  8 7 11
f  8 9 7
f  14 20 27
f  24 28 18
f  27 18 28
f  23 14 27
f  24 23 28
f  28 23 27

[pca006132]

if you update to the latest version of clipper2, does it work?

[elalish]

I did add Project() to a couple of samples tests: Bracelet and Sponge4. But yes, a dedicated test is also a good idea. Any chance you can dump out a GLB or OBJ we can test with?