Anybody know how to get the opengl texture id of a RenderTexture in Unity 2.5? I have known this can be done with GetNativeTextureID () function in Unity 3.1. But I am now using Unity 2.5 and GetNativeTextureID does not exist in 2.5. I also try GetInstanceID(), but this function seems to work with Texture2D and does not work with RenderTexture.

I use windows version and start unity application with "-force-opengl" flag.