Unreal Engine 4 is a great piece of software. I wondered if anybody knew how the GUI editor was created. Did they use their own technology based on Windows (i doubt it though) or based on something else? Or did they build this with Qt or another library? This is a question that just keeps me wondering and i can't find a lot of info on the web. Thanks in advance!
The Unreal Engine Editor's UI is made using Slate - an in-house UI system created by Epic explicitly for this. Slate is also used as the base for UMG (the UI tool inside the editor).