I've a working 360 video viewer built using Rajawali/Google VR. I'm trying to modify it to display a texture which is the output of a non Rajawali GL program, rather than displaying the StreamingTexture from the video directly (i.e. within onDrawEye I'm using a separate GL program and passing it a texture ID, it's rendering to a framebuffer with an attachment which'll be used as the texture on the sphere).
The problem I am having is that however I manage the textures (either directly with OpenGL, or using Rajawali's texture classes), they are empty within my inner GL program (i.e. black/no output when embedding into a sampler). The only thing that works is if I add the texture to a material on some dummy object visible within the scene - then the texture is available within my separate program - but that's not what I want. I've tried just adding the texture to the TextureManager, but it's insufficient to keep it around. What I'm trying to do is extremely simple and works fine without Rajawali or the GVR machinery.
What's causing even textures I'm generating and managing myself to be compromised? I don't have a minimum failing example, but could put one together with some effort.