Order independent transparency Bugs with bump texture and rendering pipeline

Yes I can confirm, the second behavior also only happens on my Laptops Nvidia graphics card.

Would it be possible for one of you (@sebavan, @CraigFeldspar) to report it to the chromium bug tracker?

The thing is that I don’t know in detail, which code is causing the problems.
The first problem seems to be an issue with the dfdx/dfdy functions and the second might be somehting with trilinear filtering?
However, with OIT deactivated trilinear filtering works, so there must be something else causing side effects, which I don’t know.

If you want me to do it, it’s not a problem, but I need more information, to write a bug that can be reproduced and solved.

The issue is I have no idea either and their teams need to investigate it I guess :frowning:

Basically the behavior is not the expected one and it seems related to derivative which would also explain the mip mapping issue as it relies on derivatives internally. The main question is why would it impact only with OIT and I can not create a smaller repro.

I also have flickering in the CD_PS’s PG with my RTX3080 TI on desktop PC.

@Evgeni_Popov Which driver version did you use, when you noticed the flickering?

The same as above (516.94).

@sebavan You don’t see the flickering when zooming in this PG?

[EDIT] Interestingly, it does work in WebGPU!

[EDIT2] Choosing D3D11On12 or OpenGL for the Angle settings in Chrome://flags make it work too. So it seems it’s a problem with the default Angle setting, which is using D3D11 (so it would be a problem with the D3D11 driver of the card).

Yup looks like it, @Evgeni_Popov can you report on the chromium bug tracker and I ll pass it around to see if it can be addressed ?

Bug reported:

https://bugs.chromium.org/p/chromium/issues/detail?id=1374333

4 Likes

forwarded thanks a lot

Thank you very much for your help and investigation!

@CD_PS

Did it ever work for you ?

It did never work for me.
But I have not tried any Chrome version prior to trying the OIT implementation for the first time.

Currently I am on version 106.0.5249.119, which gets updated automatically.

FYI: Quickly checked on MacPro and MBP +AMD GPUs (old and new version Radeon) both under iOS and Win10 session, and DID NOT see the flickering. May be something specific to Nvidia drivers?!