multithreading - How to use OpenGL ES on a separate thread on iphone?

Question

The OpenGL ES rendering loop is placed on a separate thread in my iphone application. Everything goes fine except that the EAGLContext's presentRenderbuffer method fails. The result is a blank white screen. When the same code is run on the main thread, presentRenderbuffer succeeds and the graphics is properly shown. What is the correct way of doing OpenGL on a separate thread?

Answer 1

You need to create an EAGLSharegroup.

Check out this thread on sharing OpenGL contexts between threads.

UPDATE
Previous to iOS5 I shared OpenGL contexts between threads to allow asynchronous loading of textures from disk. But iOS5's CVOpenGLESTextureCaches essentially make texture uploads free so I don't need shareGroups anymore and my code is simpler and faster.