Another possibility for the structure, where one half of the structure is a circular room on to which half of the image sequence is projected normally. The other half is a long "unrolled" wall built to follow the stretching of the projected image as it distorts laterally along the flat surface.

Again, this might ideally be built into the corner of a room, with the outside wall of the circular section facing into the corner.

Material-wise, the circular portion could be constructed from pegboard, as in drawing 2. The unrolled wall, which would be facing out into the main space, could be built from translucent coreplast, and support a rear projection of the image that viewers would be able to see before entering the structure.