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Creature
01-25-2007, 01:26 PM
Is it possible with cinemas shaders (cause I've been trying for a few hours now with no result) or is there a plugin which gives me a shader like this:

What I want to have is a scene consisting of two colours. Black is the basic colour so everything should be black by default. Now when an object is in front of another one it changes its colour to white but only in those areas where it is overlapping. See attached example.

I also can't think of an easy way to do this in post (using Fusion) and I'm kinda lost here. Maybe I tried for too long and I'm gone blind by now.
Erik Heyninck
01-25-2007, 02:19 PM
You tried proximal, eventually with a ghost object?
Creature
01-25-2007, 02:26 PM
Yes, but Proximal doesn't take the camera vector in account so when I set everything up that it looks OK at the first frame and I move the camera around it would mess the effect up.

Oh btw I need to animate both the camera and the objects here. Harden than I thought...
nutriman
01-25-2007, 03:12 PM
I've never tried but I imagine that it can be done in post when you have it rendered out with object ids and
set the mix mode to umm....difference (also try the others) for the overlapping object.
Maybe you need to render out the overlapping object seperately.
Creature
01-25-2007, 03:27 PM
Finally found a solution in post - after thinking about it hard for half a day it (of course) is one of the most simple things to do.

Render out the objects in different passes all in black, apply a brightness/contrast node to the object in front (the cylinder in my example attached to my first post) and up the brightness to make it white, use the alpha-channel of the back object (the cube) as a mask on the brightness/contrast. Done

Stupid thing that I wasted such a lot of time on huge Xpresso-setups that don't work when the solution is so simple. Ah well, that's the way life is :)
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