[gattis]

Well, QT does use GPU pipeline for all its rendering, in every backend there is, including OpenGL.

Every widget in my app above is custom as well, it was meant for a raspberry pi and a tiny touch screen. If visually customizing an existing QT widget isn't enough, you just go one or two abstractions up their tree, inherit from there, and make it do what you want using not only custom code but you can grab from many smaller QT parts. For instance in my app you grab cables out of modules and plug them into other modules, which is not a common UI thing. You just grab some of QTs bezier shape rendering stuff and draw the cables with it, and it was trivial to add gravity and make the cables springy.

It's these tools and maturity that are going to end up making your life easier on a project like this. If you go with a young framework that exists just because some sassy guy is very opinionated about how you should be forced to manage things like state and mutability, you will end up having to ram things in, and mostly working from scratch.