Remove embreex dependency for mac M1

[nepfaff]

The embreex dependency seems to prevent trimesh working on mac with arm chips. This has been discussed here to some extent.

As embree seems to mainly be an intel raytracer, would it be possible to not require this dependency for mac with M1/ arm architecture and disable the features that depend on it on these systems?

[nepfaff]

I just realized that it is not part of the core requirements but of the recommended extras. Sorry for that!

In this case, would it be possible to have an additional group "easy_arm" or similar which includes all recommended dependencies that also work on arm chips? People developing on Mac M1 is becoming more and more common.

[BuildBackBuehler]

+1 for this. Just spent 30 mins installing embree (no X) as a result of the failed install. Hopefully I can incorporate/integrate its library in a way that Trimesh can take advantage of it lol

Or I saw a mention of a Rust alternative, I'd love that, presuming its platform agnostic

[coderforlife]

Also prevents trimesh[easy] install on Linux with arm (e.g. Raspberry Pi). The comment thread linked mentions Apple M1 support is available in embree. So it seems that there are a few options:

• provide embreex wheels for Mac OSX arm and Linux (if possible, but I understand that it may not be possible)
• replace embreex with another solution (the linked thread mentions a few)
• move embreex from easy to recommended to stop preventing easy installation on two large machine categories