IOS 16.6 SSAO not working properly

[shaderbytes]

Sadly - Apple… again.

Only broken on IOS. ( tested chrome and safari )
Works perfect on windows , macOS and Android

( ipad 7gen , IOS 16.6 ) Babylon.js v6.35.0

Here is a video showing the issue , its the same wierd expanding / contracting banding based on camera angle that has being an ongoing issue in babylonjs SSAO over time ( i have posted about it before , although that was an issue on all platforms at that time and it got fixed )

RPReplay Final1706548375

[sebavan]

cc @Evgeni_Popov who might have fixed as I can not seem to remember how it was done and whether the fix would be Safari compatible

[shaderbytes]

@sebavan

whether the fix would be Safari compatible

no its buggy on chrome and safari on IOS. It works perfectly on windows , macOS and android

[sebavan]

@shaderbytes

chrome and safari on IOS

Chrome and Safari are the same thing on IOS so it could definitely be this. Nobody can currently ship a real browser on IOS only a wrapper around Webkit.

[shaderbytes]

stupid IOS , making developers life a pain again haha

[Evgeni_Popov]

In fact, @fooware improved the SSAO post-process one year ago (Improved SSAO2 when samples <16. Added more control over SSAO2 denoising filter. by fooware · Pull Request #13621 · BabylonJS/Babylon.js · GitHub).

I’m not sure why there’s a problem with Apple devices (except for the obvious reason: it’s Apple device)… Try the magic engine.disableUniformBuffers = true Ah, I think we now do it automatically when we detect a specific user agent!

Also, see:

SSAO2 blur shader issues

Thanks for the file! The problem comes from the fact that the pre-pass renderer is using a 16 bits float texture for the depth and there is not enough precision. I have a PR in progress (for SSR) that will let change the precision of this texture, but in the meantime you can force using the geometry buffer: 16 bits precision (prepass renderer): [image] 32 bits precision (geometry buffer renderer): [image] I’m running against master, that is correct, right? That’s correct!

If it’s the problem, try to use the geometry buffer renderer and see if that fixes it.

[…] Hum, that should do nothing, as the depth texture is now 32 bits by default with the pre-pass renderer:

SSAO2 blur shader issues

Note that since 5.51.0, the depth texture of the pre-pass renderer is now 32 bits. So, this PG now works without the artifacts for the towel:

[…] Ok, I could reproduce on my iPhone SE with this PG:

Babylon.js Playground

Forcing half float for the depth texture on my PC produces the same result.

The iPhone is using half float for the depth texture because float texture linear filtering is not supported:

Babylon.js Playground

Touch the screen to see the value for “textureFloat” and “textureFloatLinearFiltering”. You should get true for the first (float textures are supported) but false for the second (filtering float textures is not supported).

Unfortunately, we can’t do anything about it…

[shaderbytes]

thanks @Evgeni_Popov , that thread you referenced was me

Thanks for the break down and conclusion of the half float issue. I will mark the thread as “solved” since it is answered. At least we are aware of the issue not being something that can be fixed.

( this is an old product that is still in use by clients but a new version is under development that just uses baked lighting instead )

[sebavan]

Thanks a ton @Evgeni_Popov !!!