Hello, I’m observing a strange behaviour of the engine in rendering gaussian splatting models. It seems that the shader can’t align the splatts with the camera position. Here the test 3d model with version 7: [image] Here the same model with version 8.3 [image] many thanks!

Should be fixed : GS SH View Direction by CedricGuillemet · Pull Request #16804 · BabylonJS/Babylon.js · GitHub Please test the PR snapshot in case I missed something!

I’m looking into this while Cedric is on vacation. I’m currently trying to understand why the inversions were implemented. Are the screenshots using the MardiGrasDragon_1M.splat model? …or one of the other formats (.spz or .ply)?

Hey – I can help here. It seems both ply, compressed ply and spz are inverted when the have spherical harmonics. Before .ply supported spherical harmonics, the .ply files loaded in the correct orientation. Similarly, .splat files (no SH support) also come in the correct way. FYI, you can just inve…

Thank you @SonnyC56 , the model is the one used for test in the various playground above: https://firebasestorage.googleapis.com/v0/b/story-splat.firebasestorage.app/o/users%2FmFNJrfet99Qv9mMX2OC6hewy1xC2%2Fsplats%2FMardiGrasDragon_1M.ply?alt=media&token=d1be5a6f-d733-4de5-ab83-f39eac40a995 What I’d…

I see MardiGrasDragon_1M.ply is oriented correctly in older versions of Babylon.js until PR 16433 got merged. It’s not clear to me what the correct fix is, and Cedric says earlier in this thread that he’s not sure how to fix it, yet. I can back that PR out to go back to the previous behavior, but i…

Please do not kill SH support for plys haha - It might be a good idea to try just inverting when we detect SH in the splat

No worries we wont :wink: We will wait for Cedric to see how he wants to handle it

Hi All, just to recall that the issue still persist in 8.13. Simple test: load the dragon with supersplat and you see it correctly oriented. [image] Load the same file with Babylonjs sand box and you’ll see it upside down. [image] Thank you.

Gaussian Splatting seems to not work since version 8

Bugs

SonnyC56 May 1, 2025, 8:13pm 32

.ply gained sphereical harmonics support and once it did it is inverted like the spz is with SH

From babylonjs v 8.13.1 the compressed PLY GS with SH looks wrong

Topic		Replies	Views
From babylonjs v 8.13.1 the compressed PLY GS with SH looks wrong Bugs gaussian-splatting	6	174	December 12, 2025
Include Gaussian splatting models in .babylon files Feature requests	12	381	October 21, 2024
Help needed on Gaussian Splatting model poor quality Questions	8	177	December 31, 2025
New feature: Niantic .SPZ Gaussian Splatting and Spherical Harmonics Announcements	22	1196	September 10, 2025
Artifacts with compressed .PLY Gaussian Splat file Bugs	5	214	December 18, 2025

Gaussian Splatting seems to not work since version 8

Related topics