[aras_p]

* OpenGL is a dealbreaker since modern things in it (compute etc.) don't work on iOS/Mac; and elsewhere has a lot of driver stability problems. Does not work on any consoles.

* Metal is a dealbreaker since it does not work anywhere that's _not_ Apple.

* Vulkan is a dealbreaker since it only works on Android (mobile) or requires fairly new drivers/GPU (PC). Does not work on consoles.

* Direct3D 11 is a dealbreaker since it does not exist outside Microsoft platforms, and does not have some modern stuff (async compute etc.).

* Direct3D 12 is a dealbreaker since it does not exist outside Microsoft platforms; and on PC requires Win10.

See a common pattern? All of them can be considered "dealbreakers" for one or another reason. The (perhaps sad) reality today is, that you can't cover "all platforms" with a single graphics API.

Not that it's a big issue though... making a renderer/engine that works on more than one graphics API is not that big of a deal, compared to challenges everywhere else in game development.