And now for something completely different: science. On a sphere. I want one.
Ron Proctor writes:
Science on a Sphere uses four projectors to produce images and video on a sphere shaped screen. The Clark Planetarium in Salt Lake City has one -- it's something you almost have to see in person to really appreciate [see these photos and further info - Bart].
It really is just a big ball that hangs in the middle of the room with four projectors pointed at it.
The SoS system requires that crazy projection. It cuts the frame into four parts and feeds those to the four projectors around the sphere, along with some darkening around the edges to keep the blended image even. They project the image (or video) onto the sphere and it's like you have a planet (or whatever you want) floating in the middle of the room.
The workflow goes something like this:
In Blender, a six camera cluster with cameras pointing front, left, right, up, back, and down renders the scene into six 90º views. These views are stitched into the required projection by Hugin. We use a python script to get Blender to change cameras and output path during command line render and we use a shell script to tell Hugin what to do with the frames! Easy, right? ;)
(We're still figuring out the best way to do this, so the workflow might change if we find a faster/better way of doing things.)
The equidistant cylindrical projection can be seen here:
A 3D mockup of the data on a sphere can be seen here: