A simple app to demonstrate how to distort an image using OpenGL ES 2.0 on iOS. The image is disorted by applying a quad over the image and then mapping the quad back to a rectangle. Based on Face-Squash, an XNA demo created by @bschwind.
Build and run the app using Xcode in either the simulator or a physical device.
The red handles represent the corners of the image. Moving the handles distorts the image.