Geometry nodes support

[seandillon92]

Support for sending instance info from geometry nodes

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[seandillon92]

Hey @sindharta here is a self-review with some changes I would like to make in this PR. On a higher level, I noticed that while the VariantData works well for manual sync, auto sync requires some state management around what is dirty or not.

A quick and dirty solution to the latest commit is to change the Transform checksum to take into account the variant data checksums.

A cleaner solution would be to create a manager class for instances, similar to the entityManager. That would allow us to create our own serializable objects for instances and additional info if required. It would also decouple the instances info from meshes, so we should be able to send scene updates for instances without re-sending the mesh data.

Let me know what you think about the plan, any feedback would be appreciated!

[sindharta]

A general question. Without this PR on the Meshsync side: 549, will Unity just simply ignore the instance info ?
Might be worth testing to ensure it doesn't crash.

[sindharta]

Another idea is, can we make a certain user interaction to set a flag for sending geometry node variant data, instead of having to calculate the checksum of all variant data.

[seandillon92]

A general question. Without this PR on the Meshsync side: 549, will Unity just simply ignore the instance info ? Might be worth testing to ensure it doesn't crash.

I think it will be safe. Unity will simply not check for the variant data. I will definitely test it before merging in any case.

[seandillon92]

Another idea is, can we make a certain user interaction to set a flag for sending geometry node variant data, instead of having to calculate the checksum of all variant data.

That's a good point. At the moment I have started moving away from the VariantData approach but if we were to merge the variant data solution, I will make sure to implement this

[seandillon92]

Implemented the Instance manager class and updated the scene exported to use it. Need to validate thread safety.

[seandillon92]

Moved to #185 to fix issue with CLA client