if you're interested in graphics for games at some point you will have to learn D3D/GL there is no doubt about it. As an API OpenGL is still revalent (unfortunatley...) mostly because of the mobile market (if you are interested in that market). For desktops and consoles the picture is different.

If writing your own framework for developing games is the *right* thing to do, I really don't know.

If you've been doing XNA for 2 years it should be pretty easy to learn OpenGL.

If you want to stay with C# just Google for C# OpenGL, and either way OpenGL is simple so even if you decide against it in the end it will probably be worth it to try it out for a week or two, shouldn't take you many days to get something going.

If you want to get a game finished efficiently on more than one platform then writing your own framework is not the right thing to do, so if you're not in it for the technical parts but want to release finished products go with an engine (but I still recommend spending those couple of weeks on OpenGL, good to know what it's about :)).

Shalom,

OpenGL is relevant if you want to go "inside" the engines and simulators.

It depends on your goal, if you want to publish games I don't think starting to build another engine will suite you.

If you really like the experience and want to learn, OpenGL is the way to go. (I've been very happy with practicing low level apis!).

Cpp or Java: I personally like CPP for real time applications, it's really dynamic and suitable for low level apis where you need to manage your own memory.

with Java you have to address more frequently issues with the CPU and memory managment because it has its own memory managment system.

Shalom,

OpenGL is relevant if you want to go "inside" the engines and simulators.
It depends on your goal, if you want to publish games I don't think starting to build another engine will suite you.
If you really like the experience and want to learn, OpenGL is the way to go. (I've been very happy with practicing low level apis!).

Cpp or Java: I personally like CPP for real time applications, it's really dynamic and suitable for low level apis where you need to manage your own memory.
with Java you have to address more frequently issues with the CPU and memory managment because it has its own memory managment system.

For games using OpenGL you can check here for example: https://en.wikipedia.org/wiki/List_of_OpenGL_programs

Especially under open source games there should be indie games.

Or just go to Steam and search for indie games for Linux, though you probably have to do some more searching for each title to know whether or not they use a pre-existing engine.

2D is a good place to start, like any type of sprite-based game with shader-effects.

Someone has to write/maintain Unity, Unreal 4, Game Make, etc. Those things don't code themselves... yet.

Obviously, what I meant was if it is still relevant for me as an Indie game developer, or will it be the possession of AAA engine developers only?

Any way, I think I'm going to re-write one of my old 2D XNA games in cpp :)

Thanks