STL to SDF evaluation

[Megidd]

At the point {X: -0.8164382918936324, Y: 2.542909114087213, Z: 5.006102143191411}, the SDF value for the teapot model is returned as a positive number. It means the point is outside the teapot. But we are sure that the point is definitely inside the teapot.

Reproduce

The bug is reproduced by PR #73.

Side effects

The bug has side effects observed here: #68 (comment)

[Megidd]

The approximate coordinates for the neighbor points around the problematic {X: -0.8164382918936324, Y: 2.542909114087213, Z: 5.006102143191411} point are shown below. They all have negative SDF values, that is expected.