obs-studio: 30.2.3 -> 31.0.1

[lukegb]

This is a bump for OBS Studio from 30 to 31, which is a little bit more involved than most. There is a change from the "old" build system to a newer build system, which is still CMake-based but has been reworked to make use of the CMake presets system.

There are a few patches we (seem to) no longer need, so they've been dropped, but I haven't had a chance to test how this goes on macOS.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[fpletz]

Have you tested browser sources? For me, trying to add a browser source to the scene freezes the dialog window. Maybe we need to bump cef?

[lukegb]

Hrm, I tested it on my x86-64 box and browser sources worked fine, although I didn't add a new one or try to open its settings - maybe that's the issue. I'll take a look.

[fpletz]

Another issue I just discovered is that there doesn't seem to be WHIP/WebRTC support. I'll investigate.

[lukegb]

Browser sources still work fine for me (my output path is /nix/store/jaw30w2bh6jc52vvxk5bkkzgbbwhm02x-obs-studio-31.0.0, and the drv is /nix/store/w7nqccjcbaq7s34xafvjv5ndz0z6zfhp-obs-studio-31.0.0.drv), building at 061bcda.

WHIP is indeed missing.

[lukegb]

https://github.com/obsproject/obs-studio/blob/a0e4e3734126a7e76a871fa671be952de5c13dd8/CMakePresets.json#L75-L78 the ubuntu preset sets ENABLE_WEBRTC false, for whatever reason...

[lukegb]

On /nix/store/4vv6m7p0smvj17galaa3pibd6l3ix583-obs-studio-31.0.0 (from /nix/store/dkzk1ivb38s1ycq5yab7914h68arm4cy-obs-studio-31.0.0.drv), I get WHIP support, and the browser source doesn't seem to make OBS hang for me.

That said... it does seem to start making OBS consume 100% CPU if I add a browser source, even if I then remove it. It doesn't happen with 30.2.3, though, even with the new build system.

I bumped libcef to 127.0.6533.120 (since OBS 31.0 apparently is using 127.0.6533), but it still does it. It might be obsproject/obs-studio#11485, or thereabouts.

[lukegb]

OK, dropping obsproject/obs-browser@98d94a4 avoids the CPU spike but then reintroduces the problem with keyboard inputs causing OBS to crash in custom browser docks (which... are only enabled under X11, which confused me for a bit while trying to work out why the menu options don't show up on Wayland).

[fpletz]

I can confirm that WHIP is working now, thanks!

However, no matter what I try from your comments, my OBS unfortunately keeps hanging when I try to add a browser source or add a browser dock. 🫤

[benaryorg]

Since you're already touching the libcef related parts in this PR, could we maybe also get an overridable flag to disable the browser? Given that the entire obs-studio closure is 3.6 GiB in size and 1.8 GiB of those are libcef which some people probably aren't even using it would be nice to be able to optionally get rid of it (most rms in the fixup phase will fail when the files don't exist which makes overrideAttrs more than tedious).
I was working on a patch to make the browser support optional when I stumbled upon this here which touches the vast majority of the flags anyway, so I thought I'd mention it.

I mean.… my entire desktop system has a closure size of around 11 GiB, and 10% of those are libcef just because of obs-studio which doesn't sit right with me (and my Hydra is throwing diskspace warnings at me).
If you'd prefer I can provide a patch either on top of this PR or master, given I already wrote the latter, either here or in a separate PR.

[luzpaz]

JFYI, v31.0.1 released (https://github.com/obsproject/obs-studio/releases/tag/31.0.1)

[fpletz]

Since browser sources don't work for me either on 30.2.3 nor 31.0.x without bringing in #317589, I think we can go ahead an merge this with browser support disabled for now.

[fxzzi]

nvidia nvenc support seems to also be missing from this release as mentioned in #382666