Softwarp is a software technique to warp an image so that it can be projected on a curved screen.
There are several techniques to auto calibrate the warping by projecting a pattern and using cameras and/or sensors.
The information from the sensors is sent to the software so that it can analyze the data and calculate the curvature of the projection screen.
The softwarp can be used to project virtual views on curved walls and domes.
A problem with using several projectors on the same screen is that the edges between the projected images get about twice the amount of light.