Has anyone ever rolled their own UI in C++ with AHud::Draw() functions? It wouldn’t be too complicated. DrawText(), DrawTexture(), and DrawMaterial() would get you 90% there.
Could compose the HUD WPF Xaml style but with C++ only. Zero blueprints needed. 
Visual designers shouldn’t have to screw with c++ or xml. If I am looking for some adobe or figma guy for UI and UX I’m 99% sure it is not someone programming because a good combination appears to be rare. I’d personally get rid of the binary files and UMG with fire and prefer a text based approach similar to CSS, or an editor writing that “CSS”. It’s an entirely different topic though. If the team just perfects the core that is under UMG (Slate) and stops breaking it / not testing it, then a lot of the frustration with both systems would already be gone.
Look at how I handle my widget design for Melonade , it’s pure and simple no nonsense css. doesn’t get any cleaner. I don’t need 5 editor windows and bloated UAssets to make an app.
Try doing that in UMG and compare the effort and amount of data on your disk to the few lines of css I wrote there (did not even use textures!)
Guys, my forehead has keyboard key indents all over it. I’ve been slamming my head against UMG issues.
So no response and currently the Bug Reporting category has been closed for non fortnite users. Soooooo…
