In the documentation of the UV project modifier (which like all the entries is really vague and short) it said something about using a sphere as a projector. And a picture showing the effect on two perpendicular planes. I’d really like to find out how this is done, because so far using an object as a projector just makes it project from one axis.
It would be cool if the UV project modifier could be more like in XSI, if you are familiar with it, where the methods of unwrapping are treated as movable objects, such as cylindrical and spherical projections, and they update in real time as you move them. Pretty cool for unwrapping things like chair legs and the like.
I don’t see anywhere that says the UV modifier can use spherical projection. The closest I can see is where it says:
A swirl image is loaded in the UV/Image Editor and thus known to Blender. A simple scene, shown in the middle, has a wall and a sphere with the modifier set to project the swirl from the 35mm (perspective) camera onto those two objects.
In this example, the camera is being used to project the swirl image, not the sphere.
On the same page, it says that projections from cameras can be perspective or orthographic, depending on the camera settings, whereas projections from other objects are always orthographic, which is what you’ve already seen.