tolerenca strip around triangles

[avlonder]

Hello again,

I would like to have some kind of tolerance strip around the triangles for the ray casting.
Is this already present in trimesh / pyembree / embree?
It doesn't seem to be the case because some rays that should hit an edge of a simple cube are not hitting it.

I looked into ray_pyembree.py.
Maybe _ray_offset_factor does the trick?

BR,
Arne

[mikedh]

Hey, yeah unfortunately our logic to collect every hit using embree is a bit cheesy (more info on why it is required in RenderKit/embree#188). Trimesh's native raytracer is a LOT slower (50x or so) but does collect every hit robustly as far as I've seen. If you load meshes with use_embree=False it will use the native one:

In [1]: import trimesh

In [2]: m = trimesh.load('trimesh/models/featuretype.STL')

In [3]: b = trimesh.load('trimesh/models/featuretype.STL', use_embree=False)

In [4]: m.ray
Out[4]: <trimesh.ray.ray_pyembree.RayMeshIntersector at 0x7f4bba344eb8>

In [5]: b.ray
Out[5]: <trimesh.ray.ray_triangle.RayMeshIntersector at 0x7f4b96449438>

[mikedh]

This is actually the same problem seen as #242. Consolidating to that issue for now, thanks for the report!