macOS intel with integrated gpu - strange shadows artefacts

[mockersf]

Bevy version

Current main de8edd3

Operating system & version

macOS on an intel mac with an integrated GPU
not reproduced on an intel mac with a AMD Radeon Pro 5300M or on an arm mac

What you did

cargo run --example 3d_scene_pipelined --release

What you expected to happen

To have it display properly

What actually happened

shadows-macos-intel-integrated.mp4

Additional information

I captured a gpu frame on the intel mac, loading it on the arm mac removes the artefacts from the frame

[adsick]

looks kinda nice tho

[superdump]

The lines kind of seem to be related to the edges of triangles, as if they have something to do with rasterisation or MSAA or something. The shadow maps don't use MSAA though... What happens if you disable MSAA?

[superdump]

I poked cwfitzgerald (wgpu) about this and it's apparently similar to an issue filed against the wgpu shadow mapping demo but that seems to be a driver issue when using array textures for shadow maps: gfx-rs/wgpu#103

[Davier]

There is another MSAA issue with an intel integrated gpu (but on linux) in #3593

[luisbg]

I can repro this issue. Let me know if I can help by triaging or testing a fix.

I've reproduced it in up to date in the latest and main branches.

[nfagerlund]

Here's something interesting:

• I get this bug on a 2013 13" macbook pro with "Intel Iris Graphics".
• I DON'T get it on a 2020 13" macbook pro with "Intel Iris Plus Graphics".

Both machines are running MacOS Big Sur 11.6.5. This is with the "lighting" example from Bevy's v0.6.1 tag.

[DerKarlos]

I do have the same bug (also Issue #3423)
2018 13" MacBook Air with "Intel UHD Graphics 617"

There is no bug if I use crate rend3, also using wgpu. (may not be the same version)