Metal is a nice low-level API and you can have a tiny (<1MB) library, that can efficiently emulate modern OpenGL on top of Metal. E.g. for WebGL purposes, all

Metal is a nice low-level API and you can have a tiny (<1MB) library, that can efficiently emulate modern OpenGL on top of Metal. E.g. for WebGL purposes, all web browsers on Windows emulate OpenGL on top of Microsoft DirectX.