DXVK 2.5 - 2.5.2

[phantom485x]

Please describe your issue as accurately as possible.

On Source Engine games (Black Mesa and a HL2 build I'm working on) the lightning flickers and fps drops randomly occurs when using Reshade, it doesn't matter witch shader is active the problem persists until I disable them all. I also tried disabling them one by one and the problem persists even if one shaders remains active, no matter witch one.
2.4.9 works without problem, this bug seems to originate in the version 2.5.

In the video you can see the exactly how the flickering looks in game and also after re-enabling the Reshade profile my fps was down from 30 to 20 until i reloaded the shaders once more. The GPU usage also goes down to 60-65% (cca. 320w) from 100% (cca. 550w) when the fps drop is present.
I get the exact same behavior in Black Mesa too.

Software information

Half-Life 2 custom build based on MMod 1.3 & Black Mesa

System information

• GPU: STRIX 4090 OC
• Driver: GeForce Game Ready Driver 566.36
• Wine version: none
• DXVK version: 2.5 to 2.5.2

Apitrace file(s)

https://drive.google.com/open?id=1k2tNPZqWLCqblmi-OCFfwAIvaOmGWA7N&usp=drive_fs

[Blisto91]

Hi there and thank you for the issue. It seems we do not have access to download the apitrace

[phantom485x]

Oh, sorry abut that, it should work now

[Blisto91]

Which version of reshade are you using? Vulkan or dx9?

[phantom485x]

vulkan

[Blisto91]

Are there any specific areas in Black Mesa i should be looking at or does it take time to occur? I tried playing around with some standard shaders on both Intel and AMD without anything weird so far.

[phantom485x]

Try the Xen maps. It does happens more often there. A particularly bad one is the last chapter 5 from Blue Shift mod. I get constant lighting breaking in the first map

[Blisto91]

I have played Chapter 5 from the Blue Shift mod for a little while now but still haven't noticed anything. Might have to try on Nvidia next time i switch GPU unless you are able to get a apitrace of the issue.

Could you try giving the dx9 version of reshade a go along with dxvk? Just install the dx9 version of reshade like you normally would and then put the dxvk dll in a separate folder somewhere (doesn't matter where). Then setup the environment variable RESHADE_MODULE_PATH_OVERRIDE to point at the folder with the dxvk dll, which will make it use it instead of the regular system one.

[phantom485x]

Hy, sorry for not responding sooner. I tried what you have suggested and sadly the depth buffer is not detected by Reshade anymore with the dx9 approch. I did a lot of testing with dxvk and dx9 versions and found this:

dx9

• no more flickering
• all shaders that have nothing to do with depth work fine
• depth buffer is not detected by Reshade
• all shaders that use depth like MAXO and RTGI don't work correctly

dxvk 2.5.2

• flickering (caused by the depth buffer breaking) in certain scenarios
• all shaders break when the flickering occurs even the ones that have nothing to do with depth
• using the clear option in the buffer settings seems to help in one scenario but the problem pops again somewhere else. I could trace it to 1 draw call causing this.
  For example on d2_eli_01 map when looking in one direction in the buffer menu I can check CLEAR 3 witch shows only 1 draw call and that fixes the flickering but if I turn 180 degree the flickering is back, now looking at the buffer again CLEAR 3 shows 0 draw calls and CLEAR 5 witch had 0 calls before has 1 now. Checking 5 will fix the problem in the direction I'm facing now but will automatically unchecks 3 and if I turn back is the same story again. On other maps the CLEAR numbers may be others like 4 and 7 or 3, 5, 6 but is always the same. That draw call is always showing alone and always changes locations when you move and turn.

dxvk 2.4.9

• no flickering
• all shaders work
• tried to simulate the same conditions and the draw call shows and behaves the same as in 2.5.2 but it does not brake the depth buffer

[Blisto91]

When you say dx9 is that with or without dxvk?

[phantom485x]

With dxvk 2.5.2 and dx9 version for Reshade
dxvk 2.5.2 and 2.4.9 are both witth their respective dxvk versions and reshade vulkan version

[doitsujin]

Is there any indication that this is actually our bug, or does Reshade just make assumptions about the way we deal with depth buffers that simply don't hold true in 2.5?

Depth buffer related changes in 2.5 include not setting SAMPLED_BIT unless necessary, as well as dynamically recreating depth images with different usage flags if needed. If that is a problem for Reshade, that needs to be fixed on their end.

[phantom485x]

I sincerely don't know, my understanding about how this all works is fairly limited. All I know is that when I updated DXVK this problem appeared so I supposed it had to do with something on your end. But you are completely right it might be a ReShade related problem, I don't know.
Anyway I'm going to stick with 2.4.9 for now and test new releases of DXVK and ReShade. Maybe it will get fixed by one of the updates sometime in the future.
Thanks for the assistance and Happy New Year!