Splat shader Fix: Unable to obtain the position on the model using pickPosition when loading 3dgs Gaussian data

[yuqingyang0129]

Description

Issue number and link

Testing plan

Author checklist

• I have submitted a Contributor License Agreement
• I have added my name to CONTRIBUTORS.md
• I have updated CHANGES.md with a short summary of my change
• I have added or updated unit tests to ensure consistent code coverage
• I have updated the inline documentation, and included code examples where relevant
• I have performed a self-review of my code

[github-actions]

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[ggetz]

Thanks for the suggestion @h5developers.

@keyboardspecialist Would you mind taking a pass on this PR and decide if you would like to incorporate it into your branch?

[keyboardspecialist]

Yes, this is a change we already discussed making. This is necessary for not only picking, but for occlusion with other objects in the scene.

[keyboardspecialist]

Looks good. These flags are needed going forward.

[ggetz]

@h5developers I don't think we have a CLA on file for you. We need one to merge this PR. Could you please send in a Contributor License Agreement (CLA)?

[ggetz]

Hi @yuqingyang0129, I dropped a comment in #12545. Could you please make the CONTRIBUTORS.md update in this branch?