I'm trying to figure out if what we're trying to do is realistically feasible.
Basically, I want to make it seem as though the skyscrapers at night in a downtown area are having video of Trees/forests projected onto them turning the buildings into a more organic space. It's a bit similar to projection mapping but all done in post.
Projection mapping generally strives to hide the artifice of its fixed perspective. It sounds like you actually want to show it off?
You could treat it as traditional projection/camera mapping and simply move the camera away from the projector. If you go this route, check out Ben Rollason's Projection script [link].
Depending on the precise effect you are going for, and whether you use a 3D camera, you could also just use Corner Pin or CC Power Pin to create some fake perspective.
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