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View Full Version : Need Advice: How to simulate papers blown by wind



robertoortiz
05-14-2014, 09:47 AM
Hi guys,
I am working on a shot that requires to have a series of 81/2 X 11 papers beign blown off by the wind.
I curious on how you guys would handle this challenge.

thanks,
-R

Surrealist.
05-14-2014, 09:58 AM
I'd need a lot more specifics than that. Blown from a table? Initially in a stack? Laying around on top of one another at the start? Basically a full shot/shots description.

robertoortiz
05-14-2014, 02:05 PM
It is fantasy scene.
The shot is about a table sliding down a snowy mountain.
The table has stacks of papers beign blown by the wind and leaving a trail behind it.
-R

ernpchan
05-14-2014, 02:35 PM
Fx linker?

It seems like you'll run out of paper pretty quickly once they're all blown off the table.

Tranimatronic
05-14-2014, 03:17 PM
your stack of papers is basically a cube (with maybe a morph so it looks like it is sliding). Parent an emitter to the cube. Do a particle sim. Replace particles with "sheet'o paper geo". As the stack shrinks, translate the cube into the table. Do a few morphs on the "sheet'o paper" (based on particle age - starts flat and ends flat, curls as it flies) ta daah

Mr Rid
05-15-2014, 03:55 AM
I would first attempt a straight forward clothFX or Syflex sim. This example uses square cards, 4 polys each, with leaf shaped clip maps- https://www.youtube.com/watch?v=P4iCtdFcJao If cloth is problematic in your situation, then consider workaround techniques. Depends if you need pages to peel off one at a time, or all at once.

You might take a look at Jen's classic "confetti" scene, downloadable here under "Dynamics" - http://www.celshader.com/gallery/md/

http://www.celshader.com/gallery/md/confetti02.mov

Surrealist.
05-16-2014, 09:11 AM
One of my attempts off the top of my head would be to use an animated displacement texture with key frames (layer opacity) on subdivided sheets set to world coordinates. For full control I'd simply animate each one by hand (translation and rotation) and let the displacement texture be my wind resistance etc. which could be animated to start when the paper starts to move. From there it is up to your skill to animate the paper realistically. But let the texture do the clothy effects. And and when the cloth lands animate the opacity back down.

Probably the simplest approach with the most amount of control. And when you add up the hours dealing with dynamics, for something so simple, this one comes out ahead I think.