So I've wanted to look into about development on consoles, specifically for Xbox.
As it currently stands Microsoft provides three different (major) SKUs:
- Xbox One with and without the Kinect
- Xbox One S
- Xbox One X, or Scorpio
Dammit Microsoft, Scorpio is a much better name. Why did you have to ruin it and appeal to gamers with online names like xXxQuickScopesU4LolzxXx or xxxXXxPwnedxXXxxx.
With these three SKUs, that means hardware differs between them, similar to Playstation how they have the Playstation 4 and Playstation 4 Pro, or Playstation 3 and Playstation 3 Slim, or Microsoft themselves with the Xbox 360 Premium, Xbox 360 Arcade, Xbox 360 Elite, Xbox 360 Slim. Sweet Jesus...
Xbox takes the standard Xbox One as the equivalent PS4, Xbox One S as the somewhat underpowered PS4 Pro. And finally Scorpio (That's what I'm calling it now), as the more powerful PS4 Pro.
Where the Xbox One S upscales the output resolution of the game to 4k (Providing a 4k TV is also present), Scorpio quite literally outputs native 4k. Much like a PC would if a 4K monitor/display was connected.
So then, three different SKUs, three different hardware targets. In terms of developing for the console, the big game engines such as Unity, Unreal, CryEngine, Lumberyard (CryEngine but Amazon) are all supported. Although there really is nothing stopping you from creating your own engine that uses DirectX as the rendering process, since OpenGL isn't really supported. You know Microsoft made Xbox, Microsoft made DirectX. Xbox == DirectX...
But even still, developing for a game on Xbox One means you have to support Xbox One S and Scorpio. That's Xbox's policy, Leave nobody behind. This support my come natively if you program your custom engine right and it can scale with more CPU cores (MULTITHREADING!!! WOOO!!!), performance per core, and or GPU upgrades. The good thing about the large game engines that support the console also generally support the whole scale-ability factor.
Even if you already have a game out for the Xbox One and want to support the upcoming Scorpio release of later this year, a patch will have to be made to squeeze out that extra 5 TFLOPS of performance it can produce.
Small note, the accepted answer on this stackoverflow question helped get an understanding for what platforms support OpenGL/DirectX for custom engines.