Exaggerated contrast in 3DGS on smaller viewports

[shrimbly]

Hello. Wondering if anyone has come across this issue I'm seeing on mobile on some scenes. On a large desktop screen, this couch here looks great. But as the viewport gets smaller, something is happening with the detail of the scene, the contrast differences on the surface of the couch are being exaggerated and it feels quite 'splotchy'.

For this couch, the view from the left and right have quite different light conditions, since the space is quite dark. So I'm not sure if it's related to the training/grade, our implementation, or something else.

Link for reference: https://www.reflct.app/share-scene?token=ODQ2NWM4ZTctYjFjMC00NjcyLTk3ZTAtOGQ0NWU5NmMyYzg1OjdoVWM0MVB0elVQa0R1Q3pKbW0zbWQ=&size=4:3&automode=true

[shrimbly]

Here is a bundle cropped down to the couch only, since this is the problem area.
couch-only-sogs.zip

And a video of the issue.
https://github.com/user-attachments/assets/40bb8f17-1e0d-46aa-8bb8-25d207e0c7f4

Also, just noting that on very small viewport sizes in PostShot I am not seeing the issue.

Hope this helps!

[slimbuck]

Note: this issue was due to the scene being trained with anti-aliasing.

Our shader supports AA, but it must currently be set manually.

Postshot trains with AA by default and we need to load the AA flag from PLY header and propagate it throughout the data pipeline and set the material flag based on this.

I'm not sure how we'll handle exporting/combining multiple PLY files from SuperSplat when some have AA flag and others don't.