That is possible to do. Simply render the UI in perspective mode, instead of 2D You can use mouse-ray and polygon intersection to get the cursor coordinates inside the perspective UI. Also, the UI is exactly as good as your drawing skills are, hehe. Fully transparent futuristic green glowy thing, or plain boring Windows style, just for few examples. Drag and dropping is supported in window and scrollbar-components at least. Pagecontrol was left unfinished for now.
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