Hello there.

so it's been a year since i started using unity and made some games with it, just to get my feet wet.

I do enjoy making games, but my dream is to build a game engine from scratch, but an idea came to my mind and if it's achievable, i can make the process of creating a game engine much much faster, and the idea is to treat the unity game engine as a framework.

to my knowledge, the unity engine is very modular and extending it is very easy. I know that the engine is written in C++, with the following exceptions:

1-they expose a .NET api so that we don't have to go trough the pain of writing our games in c++.

2-The editor application's UI is written in C#, using mostly the same API that they expose to game developers.

so i want to start small, is it possible to create completely new Editor UI (custom project window, custom Hierarchy, Custom Inspector, Custom "Every window that is currently available ) and create thin wrappers around lots of Unity's functionality?

that way I can use any functionality I want and need, but have the ability to add my own custom tools.

i really need your experience and knowledge to just tell me if it's even possible.

Thank you very much for your time in advance.

“My dream is to build a car from scratch. Is it possible to do this by starting with a brand new Ford and calling it raw materials?” :-)

You can create pretty much any additional editor UIs you like on top of Unity (or rather, “using Unity”), and you can abstract most of the functionality and use your own wrapper instead in your games. After using it for a year, you should have a decent understanding of this, or at least follow the tutorials and documentation. If you are doing this to serve the need of some specific game project, that would even make sense. But if you basically want to reimplement Unity on top of Unity, maybe that's not the best way to go about it, especially not at a level of experience where you have to ask about it.

If you want to write some games, use the finished engine and add a few extensions if you need them. If you want to write an engine, and either have the experience for it or is willing to commit the time to it, then write an engine.