n-point image deformation

by Marek Dvorožňák for GNU Image Manipulation Program

During image editing it's very useful to have a possibility to deform an image in a way so that it behaves like a real world object (or object made of a rubber). At present there are many image deformation methods allowing us to do that. Some of them are implemented as tools in various software - for example Puppet Warp in Photoshop. I propose to implement a method into GIMP which behaves similarly to these methods but is more intuitive (easier to use), more predictable and should be fast enough.