Skip to content

USDScene : Fix loading of instanced skinning with unique animation #1471

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jun 10, 2025

Conversation

johnhaddon
Copy link
Member

The skel:animationSource can be inherited from ancestor prims, allowing instanced skeletons to receive unique animation. We need to account for that when generating the object hash, otherwise objects with distinct animation will falsely share a hash.

In the comment I've mentioned that ideally ObjectAlgo would be in charge of this hashing, but I'm not 100% sure that is the case. I have a prototype which does more accurate hashing using SdfPrimSpecs, and in that USDScene tracks an inherited hash to account for value clips. It may be that it would be better to track an inherited animation hash as well, which would be hard to delegate out to ObjectAlgo.

The `skel:animationSource` can be inherited from ancestor prims, allowing instanced skeletons to receive unique animation. We need to account for that when generating the object hash, otherwise objects with distinct animation will falsely share a hash.

In the comment I've mentioned that ideally ObjectAlgo would be in charge of this hashing, but I'm not 100% sure that is the case. I have a prototype which does more accurate hashing using SdfPrimSpecs, and in that USDScene tracks an inherited hash to account for value clips. It may be that it would be better to track an inherited animation hash as well, which would be hard to delegate out to ObjectAlgo.
Copy link
Collaborator

@murraystevenson murraystevenson left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

LGTM as a reasonable way of solving this for the moment. As you mention, it'll be interesting to see how/where this would fit in a PrimSpec hashed future...

@murraystevenson murraystevenson merged commit 3f89ccc into ImageEngine:RB-10.5 Jun 10, 2025
5 checks passed
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

Successfully merging this pull request may close these issues.

2 participants