Some features are super buggy on Intel iGPUs on macOS Sonoma

[marcisolti]

Describe the bug
We noticed a major regression on macOS Sonoma in our Filament implementation when using Intel iGPUs.

According to our tests, the bugs are exclusive to Sonoma. Earlier OSs do not have this issue.

Most of the artifacts are reproducable in gltf-viewer. Also, here's a video about the more interesting ones: https://youtu.be/3DD6_20G33k

List of the artifacts we noticed:

ImGui is artifacty.

TAA, FXAA, SSAO, SSR is artifacty.

DoF is also broken. DoF + TAA + Bloom combination results in a spectacular artifact.

If I turn OFF all post-processing sub-options, but leave post-processing ON, while setting MSAA 4x to OFF, I get a similar artifact. Turing post-processing OFF OR MSAA 4x ON removes the artifact.

Other important findings

• If I disable the buggy feature in gltf-viewer, sometimes I have to resize the window to remove the artifacts.
• Refractive shader with refractionMode set to screenspace is broken similarly. cubemap is ok.

To Reproduce
Try the aformentationed features in gltf-viewer on an Intel iGPU on macOS Sonoma.

Expected behavior
No artifact.

Screenshots
See above.

Logs

konczl@Leventes-MacBook-Pro-2 samples % ./gltf_viewer 
FEngine (64 bits) created at 0x7fa440024000 (threading is enabled)
FEngine resolved backend: Metal
Selected physical device 'Intel(R) UHD Graphics 630'
Supported GPU families: 
  MTLGPUFamilyCommon3
  MTLGPUFamilyMac2
Features:
  readWriteTextureSupport: true
Backend feature level: 3
FEngine feature level: 3
Requested linear format but KTX contains a sRGB format. 
Requested linear format but KTX contains a sRGB format. 
Texture Decoder has 14 background threads.

Desktop (please complete the following information):

• OS: macOS Sonoma 14.4.1
• GPU: Inter UHD Graphics 630
• Backend: Metal

Smartphone (please complete the following information):

• Device: n/a
• OS: n/a

Additional context
n/a