I have been posting on here like crazy trying to get my fragment shader code to work. I finally stumbled upon something that might fix what is wrong.
I am trying to use OpenGl ES 2.0 on Android to manipulate the camera preview. To do this, I need to load my own texture to the fragment shader. Thus, I have the camera's texture as a samplerExternalOES, and my own texture as a sampler2D. I saw one reply saying there is a bug with trying to use both these texture types in one fragment shader. Can anyone shed some light on this for me? Why can't you use a samplerExternalOES and a sampler2D texture in the same shader? And what would be the best way around this problem?