I’m trying to reverse this example. In this example a shader is applied to a background image, while the foreground image is not affected.
However when I try to do the opposite, that is apply the shader to the front one and ignore the back one, the back image is not visible anymore.
I tried it by modifying the following line:
More generally, I’m interested in being able to selectively apply shaders to specific images on the scene; reversing the current example is a first step in that direction.