CI: Add capability for native Apple Silicon and Universal binary builds

[PatTheMav]

Description

Adds the necessary changes to build OBS on macOS for x86_64, arm64, and universal binary builds. Heavy lifting is done by cmake itself (via the CMAKE_OSX_ARCHITECTURES flag) which allows compilation for single or dual architectures.

Notes:

• This PR requires all the work done in the cmake overhaul PR, which is why its commits/changes are included here. Once that PR is merged, the rebase will make those additional changes disappear
• For the time being this doesn't work with browser source enabled (which it is by default) as we don't have a native patched CEF build for arm64 available
• That said, with browser source functionality disabled, this will compile a fully native Apple Silicon build
• This PR uses the recently updated obs-deps version that contains universal libraries
• Dependencies are not expanded to /tmp anymore but instead in the obs-build-dependencies directory used by all other build dependencies. This avoids the issue of obs-deps disappearing at reboot (as macOS empties /tmp) and also makes use of the new obs-deps not using absolute path IDs in signature anymore

Motivation and Context

• Future-proof OBS for Apple Silicon machines
• Proper multi-arch handling for macOS
• Dependency cleanup

How Has This Been Tested?

• Universal, x86_64, and arm64 builds created on x64_host
• Builds running on their native archs
• Universal builds running on both archs with their native runtimes
• Further tests pending

Types of changes

• New feature (non-breaking change which adds functionality)
• Code cleanup (non-breaking change which makes code smaller or more readable)

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.

[PatTheMav]

@GeorgesStavracas Can you make sense of this? The Flatpak step complains:

Build failed: Error: ENOENT: no such file or directory, open 'CI/flatpak/com.obsproject.Studio.json'

But the file is clearly there: https://github.com/PatTheMav/obs-studio/blob/universal-build/CI/flatpak/com.obsproject.Studio.json.

[iambenmitchell]

That said, with browser source functionality disabled, this will compile a fully native Apple Silicon build

So I assume we can now use BUILD_BROWSER=OFF to compile OBS for Apple Silicon? Where would I go about specifying this flag?

[Fenrirthviti]

It is a cmake flag.

[iambenmitchell]

It is a cmake flag.

Yes but how do I actually apply it? Is it possible to apply it to the CI build script? Because I tried making a directory in the root called build and then running:

cmake -DCMAKE_OSX_DEPLOYMENT_TARGET=10.13 -DDISABLE_PYTHON=ON -BUILD_BROWSER=OFF ..

But I got a luajit error. And there was no bottle to install it. Compiling it from source gave me an error so I gave up

[RytoEX]

It is a cmake flag.

Yes but how do I actually apply it? Is it possible to apply it to the CI build script? Because I tried making a directory in the root called build and then running:

cmake -DCMAKE_OSX_DEPLOYMENT_TARGET=10.13 -DDISABLE_PYTHON=ON -BUILD_BROWSER=OFF ..

But I got a luajit error. And there was no bottle to install it. Compiling it from source gave me an error so I gave up

LuaJIT has nothing to do with the browser source. LuaJIT is used in the obs-scripting module. You need the latest LuaJIT 2.1 branch which should be included in our dependencies package. We don't use brew for dependencies.

Otherwise, you can disable the scripting module entirely by setting ENABLE_SCRIPTING to OFF, or disable Lua support by setting ENABLE_SCRIPTING_LUA to OFF.

[PatTheMav]

This PR is based on the CMake rework - to disable browser sources you have to pass a value for the ENABLE_BROWSER_SOURCE cache variable.

CMake cache variables are passed using the -D switch (so in full you have to pass -DENABLE_BROWSER_SOURCE=OFF.

[RytoEX]

Hi, is there a tutorial on how to use this PR to build/download binaries for apple silicon powered Mac? Thx!

Download the latest builds from the master branch by checking for the latest build from the obs-studio repository's main page.

1. Click the green check mark.
2. Click "Details" on any entry listed in the menu that appears.
3. Click "Summary" on the page that loads.
4. Scroll to the bottom of the page and download the macos-arm64 build, currently labeled "obs-macos-arm64".
   

[Chiitoo]

I didn't have a chance to test this before merge in recent times (I guess I might have only tested #4560), so I only now noticed that VST will be required always. Sort of.

I do see the ENABLE_VST at https://github.com/obsproject/obs-vst/blob/master/CMakeLists.txt#L39 but that doesn't help if the module isn't there during build. This might be mostly an issue with source-based packaging only, so I wonder how desirable it will be if I (or someone else) includes the check in OBS Studio itself like how it used to be.

[gxalpha]

This looks intentional to me (and honestly there really isn't a reason to not have a submodule cloned).
However, we're looking to merge obs-vst into the main repo anyways, so this will just resolve itself.

[Chiitoo]

Well, if nothing else, it seems like unnecessary traffic. :]

Looking more into it, it seems the same would happen if obs-browser is missing. Both of them are behind 'ENABLE_PLUGINS', but it's either all or nothing then.

[mrfruteroPR]

Is it posible to use the NDI and VLC playlist plugins?

[gxalpha]

All built in plugins (like VLC) work.
Third-party plugins, like NDI, have to be updated by their authors first.