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View Full Version : gradient seems to animate in 3D space

Ernest Burden
05-10-2006, 09:55 PM
Using a gradient with turbulance to create a noise pattern in RGB as a driver for displacement seemed like such a grand idea. It works wonderfully...until you do animation. Then it causes the displacement to animate about, even though the object is standing still. I want a 3D pattern so that copies of the same object will react to the 3D noise and displace randomly depending on where they are. I used this to make the bottome of curtains be different, even though they were an instance. It works perfectly in a still. But run frames and it dances about like there's a heavy wind. I had thought it was due to the 'random seed' of different CPUs while rendering animation frames, but I just tested it on one machine (one single-core CPU) and the bumps move every frame.

Are there any settings that will do what I wanted?

http://acmedigital.com/temp/disp-moves.jpg


The reason for the RGB noise is that displacement is really just an up/down effect on a normal, but use the RGB/world mode and it displaces in 3D space based on the color. So its perfect for adding variation to fabrics and organic objects that will not tile with every new instance or copy of itself.
LucentDreams
05-10-2006, 11:29 PM
try changing frequency to 0% :thumbsup:
Ernest Burden
05-11-2006, 12:08 PM
try changing frequency to 0% :thumbsup:

Kai

Thank you, that is it. I had played with that setting but forgot it with regard to animation. The noises have settings for 'animation speed' and 'movement' while the gradient/turbulence does not, so I had thought that it could NOT be animated (lack of setting to do so) and that 'frequency' referred to a pattern in the turbulance. But you are absolutely correct, setting to zero locks the deformation down.

Anyway, this technique allows for introducing variation into copied objects like seat cushions and hanging fabrics. As I said it works on instanced objects, too, so long as you use world space. So its infinite variety with a single material setting. very useful.

Thanks for the answer!
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