metal-cpp VS MoltenVK

My understanding is the proliferation of “XYZ-cpp” AI frameworks is due to the c++ support in Apple’s gpu library ‘Metal’, and the popularity of apple silicon for inference (and there are a few technical reasons for this): https://developer.apple.com/metal/cpp/

This is basically also what the "official" C++ API for Metal does (https://developer.apple.com/metal/cpp/), it's an automatically generated bindings wrapper which calls into ObjC runtime functions.

I also dabbled a bit with this idea by parsing clang AST-dumps of macOS system headers:

https://github.com/floooh/objc-ast-experiments

Unfortunately this is very brittle, and also broke on ARM CPUs, I guess the shim code needs some ABI adjustments (famously, objc_msgSend has multiple "ABI shapes": https://www.mikeash.com/pyblog/objc_msgsends-new-prototype.h...).

There's official C++-interface: https://developer.apple.com/metal/cpp/

It doesn't matter if the project driven by Microsoft or not, the cat (of automatically generated language bindings) is out of the bag. E.g. Zig is using the same approach without being an official MS project: https://github.com/marlersoft/zigwin32, and Apple has an automatically generated C++ API for Metal (https://developer.apple.com/metal/cpp/).

In the future, the question won't be "what language do I need to learn to code on this platform", but instead "are there language bindings for my favourite language".

this? https://developer.apple.com/metal/cpp/

Doesn't it just use objc/runtime.h and if anything is missing you can just add your custom api calls?

Metal has C++ bindings (which cover a full app lifecycle so you don’t have to touch Objective-C/Swift at all) but they’re based on the Objective-C memory model. There are some helper structs mimicking shared pointers, but you’ll still need to understand the basics of how an autorelease pool is used to avoid memory leaks and/or bad access crashes.

On https://developer.apple.com/metal/cpp/ check Foundation folder and all those nice Object::sendMessage().

People have already mentioned Metal, but if you want cross platform, https://github.com/gfx-rs/wgpu has a vulkan-like API and cross compiles to all the various GPU frameworks. I believe it uses https://github.com/KhronosGroup/MoltenVK to run on Macs. You can also see the metal shader transpilation results for debugging.

MoltenVK doesn't support geometry shaders for ~3 years now[0]

[0] https://github.com/KhronosGroup/MoltenVK/issues/1524

Games written with Vulkan can run on MacOS with the help of the MoltenVK [1]. You don't need to rewrite the game, just recompile for MacOS. The game can use Vulkan API but loads the MoltenVK shared library at runtime. It acts as a translation layer for Metal which is very similar to Vulkan. There are some gotchas, such as you can not use geometry shaders because Metal does not support them.

[1]: https://github.com/KhronosGroup/MoltenVK

https://github.com/KhronosGroup/MoltenVK

Translating between rendering APIs is not really the problem. The GPU design is more different than the API is.

Khronos maintains MoltenVk though, which is "official" as it gets: https://github.com/KhronosGroup/MoltenVK

...technically, Vulkan on Windows is also only supported via 3rd-parties (the GPU vendors), Microsoft doesn't support Vulkan either ;)

MoltenVK implements large parts of Vulkan on top of Metal for Apple systems. It isn't full Vulkan but it makes porting Vulkan games to OS X easier.