[pjmlp]

Metal and driver SDKs require C++.

[eridius]

Metal is Obj-C.

[pjmlp]

Then try to write Metal shaders in Objective-C.

[eridius]

Metal shaders != Metal API. Metal API is Obj-C. Metal shaders are written in MSL (Metal Shading Language). C++ is still not involved, though MSL is admittedly based on C++.

[pjmlp]

Metal API ⊇ Metal Shaders, it is useless without them.

https://developer.apple.com/metal/Metal-Shading-Language-Spe...

"The Metal programming language is a C++14-based Specification with extensions and restrictions. Refer to the C++14 Specification (also known as the ISO/IEC JTC1/SC22/WG21 N4431 Language Specification) for a detailed description of the language grammar. This section and its subsections describe the modifications and restrictions to the C++14 language supported in Metal."

Also, the MSL and Objective-C compilers are built on top of LLVM, written in C++.

[eridius]

I don't know what point you're trying to make. MSL doesn't link with the rest of your program. No matter what language you use for your program, the shaders are written in MSL. For my program if I use Rust or C++ or Obj-C or Swift or a microscopic magnet and a very careful hand, I write my Metal shaders in MSL.

[pjmlp]

1 - MSL is a set of extensions on top of C++14

2 - Metal requires MSL

3 - IO Kit is a C++ framework for macOS, iOS, iPadOS and watchOS drivers

4 - Metal GPGPU drivers are written in IO Kit

5 - Metal is useless without MSL and GPGPU drivers

6 - Ergo, Metal requires C++