title: how to set/get pixel on a texture in OpenGL ES on iPhone?
body: <p>I am trying to Google for what I've mentioned in the title, but somehow I couldn't find it. This should not be that hard, should it?</p>
  
  <p>What I am looking for is a way to gain access to an OpenGL ES texture on iPhone, and a way to get/set pixel with it. What are the OpenGL ES functions I am looking for?</p>