@GeoffN, the problem is that there's literally nobody on the university that knows the topic.
I know that DirectX is not a game engine. I already started developing the engine and I'm using DirectX for the rendering. I managed to create a good base for 'game engine algorithms' to introduce as I can already render objects with physics, textures and lights, handle inputs and update the game logic. I'm also familiar with other engines, as previously I developed a few game projects (mainly in UE4), but now I want to try something new and in lower level programming. Unfortunately, I still can't come up with a proper thesis.