On the game I'm developing (with cocos2d) I had some arbitrary chipmunk polyShapes on the game scenes, that are working fine, currently I'm rendering just the border. But what I need is to texturize them like this:

Currently I had implemented this generating a texture2D with the textureMgr and then I tried to apply (not very well) that with some openGL calls. Is there any better/easier way to texturize an polygon inside cocos2d?