Fast generation of curved perspectives for ultra-wide-angle lenses in VR applications
Classic ultra-wide-angle perspectives are not realistic and often misleading, nevertheless, they have to be used in many applications where the viewer needs a survey of the scene. Current hardware, however, only supports classic perspectives. We present a fast polygon-oriented algorithm that allows the use of curved perspectives in order to overcome several drawbacks, but at the cost of non-linearity. Space is projected onto a sphere rather than onto an image plane. The spherical coordinates are then interpreted two-dimensionally. We discuss the advantages and drawbacks of several approaches to curved perspectives. Time measurements show that real-time animation of reasonably complicated scenes can still be done; the overhead (additional cost of CPU-time) is less than 20%. Thus, curved perspectives are a good choice in virtual reality applications where ultra-wide-angle lenses have to be used.
curved perspectives wide-angle lenses orthogonal projection stereographic projection cylindrical projection mollweide projection eckert projection