So here is what i would like to try to do:
Say i have two game objects A and B
They have a bunch of children, i want object A and all its children meshes to render in black and white but B to be normal. Is this possible with post processing at all ? If so how do you do it?
If not - how would something like this be achieved?
The two camera method:
Put A and it’s children on a separate new layer and render them with a camera that only renders that new layer and has your black-and-white post effects. Then render the scene with a second camera that renders all layers except your new layer. Make sure you set the post effects camera to render first and the second camera to not clear what the first camera renders.
that will render the first camera on top of everything else, even if they’re behind a wall or occluded by some object.
What you need is to use stencils. Sadly it’s not a commonly used method and it appears to be a bit tricky.