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Not random 3d objects bit 2D compatible abstractions similar to windows that render what would be a window on one face for regular apps but for 3d apps, different faces and relationship between cubes can be configured
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Sun's "Project Looking Glass" did some of this.
https://en.wikipedia.org/wiki/Project_Looking_Glass
It's the only windowing environment I have seen that uses the fact that windows have 2 faces: the front holds content, the back holds config.
It was a clever design but it didn't get far.