splats display wrong side when moving out of screen

[kmeirlaen]

I'm not sure how to describe this, so here is a video...

2026-06-10.10-04-26.mp4

And from the other side:

2026-06-10.11-16-30.mp4

Any way to solve this?

[mrxz]

By default Spark sorts the splats radially. This has the benefit that rotating the view (without moving) doesn't require (re)sorting. So if you turn around you would see the sign rendered properly. What happens when you move the camera backwards such that the sign comes into view is that it's being rendered with stale ordering, while a new sort operation is kicked off. Until that sort finishes you'll see an incorrect result.

Interestingly, for the videos you've posted that means being on the other side of the sign, while rendering it in an outdated order (from the other side of the sign), which is precisely inverse of what it should be, hence seeing the wrong side of the sign.

Any way to solve this?

Sorting performance should see an improvement in the next release (see #327), which should reduce the time the incorrect result is visible. It won't completely eliminate the issue, though, as rendering won't wait for the sorting to complete.

You can try and see if disabling radial sorting (sortRadial: false) results in a better experience for your use-case. For the movement in the videos this would instead result in the sign "popping" into view after a sort. This is due to the fact that the non radial sort also culls splats behind the camera during the sorting stage. But this also means turning around quickly can show previously culled areas for the same span of time, which is generally worse.

[kmeirlaen]

Thanks! I look forward o the new release...

[joaomelorodrigues]

Not sure if related, but in the video i rotate a bit faster and get this issue:

Screen.Recording.2026-06-10.at.16.40.45.mov-converted.mp4

(I'm using the latest main branch with dist built that contains lodTraverseMode types)