IOS5 GLKit GLView and Hit testing

Question

In the new GLKit GLView reference, there is this warning that is emphasized:

Important: Your drawing method should only modify the contents of the framebuffer object. Never attempt to read the pixel information from the underlying framebuffer object, modify or dispose of the framebuffer object, or read its other properties by calling OpenGL ES functions. Instead, rely on the properties and methods provided by the GLKView class

Previously, with EAGLView the best practice published all over was for hit testing which included the use of glReadPixels using a framebuffer which was rendered but not presented.

With GLKView the only thing that seems to come close is a "-snapshot" call to make a UIImage object from the render. Then dig out the pixels. This seems very inefficient.

Is there a "best practice" for hit testing with the new GLKit funcitons? It seems that binding and rebinding of a seperate framebuffer are possible but then I'm not sure of what the dramatic warning in the GLKView reference means.

Any ideas on the best approach for hit testing when using GLKit?

Answer 1

Check out this very informative SO post which includes sample code. I believe it is exactly what you're looking for- it worked great for me.