I have an iPad app I am working on and one possible feature that we are contemplating is to allow the user to touch an image and deform it.
Basically the image would be like a painting and when the user drags their fingers across the image, the image will deform and the pixels that are touched will be "dragged" along the image. Sorry if this is hard to understand, but the bottom line is that we want to edit the content of the texture on the fly as the user interacts with it.
Is there an effective technique for something like this? I am trying to get a grasp of what would need to be done and how heavy an operation it would be.
Right now the only thing I can think of is to search through the content of the texture based on where was touched and copy the pixel data and do some kind of blend on the existing pixel data as the finger moves. Then reloading the texture with glTexImage2D periodically to get this effect.
Any kind of insight or info is appreciated.