How to modify pixel data after getting the pixel information

Question

hello, I am reading pixel information using the function glreadpixel(). can any one suggest me how to do operations on them after getting them.i would be very thankful if anyone provide me a sample code to refer. Thankyou..

Answer 1

http://usuarios.lycos.es/hernandp/opengl.html

That's one example I wrote years back. Check out pixel effects demo to see how to read pixels and treat them. It's standard OpenGL and does not use any programmable shaders, so I think it's perfectly portable to the iPhone.

Hope that helps. And tell me about your iPhone port ;)