Trick for animating partial visibility

[ockham]

Here's a little trick for "opening up" part of an object that doesn't have separate materials. I used this on Sparky's bones for the Big Cat. I'm doing anatomy courseware and needed to "open" each side of the skull to show a brain inside.

The trick involves the P variable node. In this case I set the Z value of the variable to 1 and the others to 0, because the skeleton is placed sideways. Note that the P variable doesn't have any connection to U and V of the figure; it's solely based on the directions in the scene.

The animation or flipping is done with the two numbers in the Add node. Everything else is constant.

 

[English Bob]

Awesome. Noted!

Edited to add: I can imagine driving the p node x, y, and z inputs with some math nodes to make a more complex intersection... Hmm...

 

[ockham]

Yes. If nothing else, you could certainly animate the active one (Z here) for a sort of 'peel-back' effect.