GS ratio

[CedricGuillemet]

follow up https://forum.babylonjs.com/t/gaussian-splatting-looks-bad-with-custom-aspect-ratio/50629/3
regression with #15104

[bjsplat]

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[bjsplat]

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[bjsplat]

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[RaananW]

Visually I don't see any difference. VR works in this one as well, so I am ok with this PR, but what is the change?

[CedricGuillemet]

Let's wait for CrashMaster to test the fix. I'm not sure about the fix. Maybe shader transpilation and undefined behavior.

[bjsplat]

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.

[RaananW]

Sorry, correction - this brings back the VR issue. It is essentially a rollback to the original behvior

It seems like this is a ratio issue. maybe as a temp solution until we can fully debug this, we can have two modes, one for rig cameras, one for standard behavior?

[CedricGuillemet]

I think a change needs to happen here :

Babylon.js/packages/dev/core/src/Materials/GaussianSplatting/gaussianSplattingMaterial.ts

Line 214 in 17ad523

const renderWidth = engine.getRenderWidth();

I guess, in case of VR, getRenderWidth is the size of both views and it should not. A quick check with VR is to divide the width by 2 and see how it goes. Can you do the test @RaananW ?

[RaananW]

I think a change needs to happen here :

Babylon.js/packages/dev/core/src/Materials/GaussianSplatting/gaussianSplattingMaterial.ts

Line 214 in 17ad523

const renderWidth = engine.getRenderWidth();

I guess, in case of VR, getRenderWidth is the size of both views and it should not. A quick check with VR is to divide the width by 2 and see how it goes. Can you do the test @RaananW ?

I did try that previously, and it didn't work. But let me check again to be sure

[RaananW]

Just pushed a change. Once built it will be great if everyone can check it. It changes the viewport's width (and viewport's only) when rendered in a rig camera. Seems to be fine in VR and on desktop

[CedricGuillemet]

Tested by forum users and seems all good !!!