Broken TAA with Intel Iris Xe on Windows

[Flopster101]

Basically, shimmering is seen (especially at the distance) and blocks even look a bit wobbly. I can't reproduce this with other shaders that use TAA, and it also doesn't happen on Linux (for some reason).

Here is a vid trying to show the issue: https://www.youtube.com/watch?v=B-7IcRWCwME

Increasing the quality for various of the performance options does help reduce the effect a bit, but I can't afford that on my system. One thing that looks really affected by this is light shafts, which have a lot of noise (see image below).

Version: r5.1.1 Shader mod: Iris 1.6.10

[EminGT]

Thank you for the detailed report. Sadly, this is such a weird driver issue that I don't think I can do much about it without getting my hands on some Iris Xe hardware and messing with random things for many hours, which can't happen anytime soon

[Flopster101]

Thank you for adding the option to disable TAA on Complementary 5.2.1 as it certainly does help mitigate the wobbly and shimmering image issue while standing still (even if it makes the noise more visible, as expected).

[Flopster101]

I found a fix/workaround.

Editing file shaders/lib/pipelineSettings.glsl and changing the value of colortext2Fomat from RGBA16 to RGBA16F the issue seems to be fixed for me:

const int colortex2Format = RGBA16F;         //taa & previous depth

I uploaded a video to demonstrate it: https://youtu.be/fqJ_4rrZaTs

I got the idea to try that by looking through the code of RethinkingVoxels (where TAA works fine, and I know it's based on Complementary), which already uses that value starting from this commit.

[EminGT]

OH! Thank you so much. It was a simple issue after all. I'll release a fix version soon

[Flopster101]

Awesome, I'll be waiting for that :)

For future reference, this Intel support article seems to document this behavior: https://www.intel.com/content/www/us/en/support/articles/000093274/graphics.html

And since it only affects the Windows version of the drivers, I guess they "fixed" it on MESA.