DOOM 3 BFG: Textures flickering on OS X Sonoma (Apple M3)

[psihonavt]

Hi,

I'm running DOOM3 BFG Steam version on MacBook Air M3 (Sonoma) using the RBDOOM 1.6.0 I downloaded from macsourceports.
While the game runs totally fine, there are some problems with textures rendering:

I tried all available graphic options in the Settings menu, but to no avail. I attached the console output if that would be of help. I'd appreciate any help on to how to fix my textures 🙂

d3bfg.log

[SRSaunders]

Thanks for reporting this. Are the texture problems only on your character’s hands or weapons? If so you can try setting the cvar r_useGPUSkinning to 0. This can be done in your autoexec.cfg file that is read during launch.

Please let me know the result since I thought this problem was solved, at least on M1. I don’t have an M3 so can’t test there at this time.

[psihonavt]

@SRSaunders setting r_useGPUSkinning to 0 fixed the flickering, thanks! And to answer your question – yes, the texture problems appear on NPSs/enemies as well.

I'd be happy to help you debug this issue.

[SRSaunders]

@psihonavt thanks for offering to test this on your M3 setup. However I suspect a possible driver issue as the culprit.

Earlier versions of macOS and/or MoltenVK showed this problem on M2 Max, and possibly M1 Pro (see #763). And back in January 2024 I observed the same problem on my M1 and had to disable GPU Skinning for Apple Silicon (see #854). However, as of Feb 2025, using later OS/driver versions, the problem disappeared and I removed the workaround (see #974).

The macsourceports.com version bundles fairly up-to-date RBDoom3BFG code and MoltenVK versions (MVK 1.2.11). And in my case I am running Sequoia 15.5 on my M1 Air test machine. No issues running the macsourceports.com build on that. Another macsourceports.com user reported a different issue (#1000) but no mention of flickering textures.

However, I am still interested in figuring out this problem expecially if it has reoccurred on a different M-series variant. If you are able, you could try building the game from source using the rpsubsets-and-pc branch in this repo. This is the default for macOS and detailed build instructions are documented in the README. I would be interested in whether the issue appears for debug builds (using cmake-xcode-debug.sh) vs. release builds (using cmake-xcode-release.sh). Also, are you running the most recent version of Sonoma with up-to-date OS and driver versions?

[SRSaunders]

@psihonavt I decided to try and recreate the issue with an older build of RBDoom3BFG with an older Vulkan SDK, but running against a modern macOS version on my M1 Air.

I used:

1. RBDoom3BFG commit 8f84e54 (Oct 12, 2023)
2. Vulkan SDK 1.3.250.1 (June 29, 2023) containing MoltenVK 1.2.4
3. macOS Sequoia 15.5 (May 12, 2025) on M1 Air

I built for Release and flickering did not occur with skinned textures, i.e. with r_useGPUSkinning = 1 (on). This is in contrast to several years ago with the same lineup running on an older macOS version (Ventura 13.5 rel. July 24, 2023) where flickering occurred. This seems to indicate it's the macOS version and/or the associated Metal driver for Apple Silicon that was at fault. Please make sure your version of Sonoma is up-to-date. If this does not help, then just run with r_useGPUSkinning = 0. I would not bother with the build-from-source test I suggested above.

[psihonavt]

Thanks! I'll attempt building from source later this week, just out of curiosity.

…

On Tue, Jul 22, 2025, 10:18 AM SRSaunders ***@***.***> wrote: *SRSaunders* left a comment (RobertBeckebans/RBDOOM-3-BFG#1041) <#1041 (comment)> @psihonavt <https://github.com/psihonavt> I decided to try and recreate the issue with an older build of RBDoom3BFG plus an older Vulkan SDK, but running against a modern macOS version. I used: 1. RBDoom3BFG commit 8f84e54 <8f84e54> (Oct 12, 2023) 2. Vulkan SDK 1.3.250.1 (June 29, 2023) 3. macOS Sequoia 15.5 (May 12, 2025) I built for Release and flickering did not occur with skinned textures, i.e. with r_useGPUSkinning = 1 (on). This seems to indicate it's the macOS version and/or the associated Metal driver that is at fault. Please make sure your version of Sonoma is up-to-date. If this does not help, then just run with r_useGPUSkinning = 0. I would not bother with the build-from-source test I suggested above. — Reply to this email directly, view it on GitHub <#1041 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAFLXKQEZ2SORWHRSMUMDGL3JZW5XAVCNFSM6AAAAACB5BHB7KVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTCMBTHE2DINBTGI> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[psihonavt]

@SRSaunders I built it from source from the latest commit in rpsubsets-and-pc, and the flickering is still there:

MoltenVK: dyld[94163]: <450BA480-03A0-3321-8F09-B615A3C20A14> /opt/homebrew/Cellar/molten-vk/1.3.0/lib/libMoltenVK.dylib
VulkanSDK Vulkan Instance Version: 1.4.313
Metal Support Metal 3

I've tried building the game with an older SDK, but it didn't work due to absent VK_EXT_layer_settings extension in earlier versions. Next, I'll try to build from an older commit (I tried once, but was spooked by the number of errors 😁)

And just to reiterate, I've been playing the game with disabled gpu skinning, and it's been a blast. I'm messing around out of curiosity. Also, a question: you mentioned that my OS X Sonoma might have an older Metal driver. How can I check the driver version?

Thanks!

[SRSaunders]

@psihonavt thanks for pursuing this further. Building from the latest commit in rpsubsets-and-pc using an up-to-date VulkanSDK is the right thing to do.

My test using an older commit+SDK was only to check if I could reproduce the issue on my M1 Air against a modern macOS, and I couldn't. That was my way of narrowing down the issue. I wouldn't try that yourself since multiple things have changed in the code base and you may have trouble with dependencies - I know how to solve those but it may be difficult for you.

I'm glad you can play the game with GPU skinning disabled. The only question I still have is the specific version of Somona you are using and the machine. Is Sonoma the most recent update, or are you using an older patch level? And are you using an M3 Air 13" (how many CPU/GPU cores) or an M3 Air 15"? Thanks.

[psihonavt]

I have a 15'' M3 Air. My OS X has the latest update available from Apple (14.7.6).

[SRSaunders]

I have a 15'' M3 Air. My OS X has the latest update available from Apple (14.7.6).

I was hoping you were using an older release level of Sonoma, with older Metal drivers for Apple Silicon as a plausible reason for the issue. However, you are using the most up-to-date version/drivers so that should not be the reason.

You are the first person to report the flickering issue on Apple Silicon > M2. There was a previous report by an M2 user with a different problem, but they did not report any graphics corruption. And flickering does not occur on my M1. I wonder if there is a Metal or MoltenVK issue with M3 and/or M4 chips that I have not seen due to lack of hardware. Perhaps it's time for me to buy an M4 machine for dev/testing.

In the mean time keep using r_useGPUSkinning = 0 until I can duplicate the problem and try to correct or work-around.