[giaur]

I guess you're talking about a 3D-TV compatible GUI (tab/ou, sbs) which IMO is a bit different. There is ofc a benefit to at least have support for it. If it needs to have support for a z-index is another thing.

Indeed. Not 3D- rendered models/textures etc, this doesn't make any sense. I mean really flat controls, but with different z index. With no any additional rendering required, the only need is to scale exisiting controls correctly and split (hou/hsbs). For open gl 3d rendering - I can imagine it for open gl visualisations only, not for main gui.