Jittering or wind in non-dynamic fur.

 
 
 
Posted by:d3d
Data created:4 June 2019

Hi,

I wasn't allowed to post in the defect forum, hopefully this is the right spot.

I am back to testing Ornatrix and have run into an issue where there is no dynamics of any kind and I translated the character in space (trying to simplify from the shot animation). But there appears to be some kind of wind-like forcer or jitter in the fur.

I have checked that remember roots are turned on in the hair from guides and the guides from mesh (one yellow and two green), and checked the emitter mesh is not set to best shape.

I checked the underlying mesh to make sure there was no jitter there, but otherwise not sure why fur without dynamics is acting like this.
Oh, I tried baking or collapsing the edit guide node, which did not work, and then tried collapsing whole stack which worked better but cause another issue of disappearing fur.

Any tips would be great, as this has me fairly worried for when we actually need to sim the fur for a bunch of characters.

Thanks,
Dax

 

For anyone that runs into this later, the normalize operator was causing extreme jitter in non-dynamic scenes. 

Tweaked the value and it stopped the wind tunnel effect. 

Hi,

Sorry, I missed this post. 

The Normalized operator is constantly trying to normalize the hair strands, so if the strands are simulated, moving around, Normalize is keep trying to do its job and normalize the new strands positions, this is why you get jittering. We are going to approach this design issue but in this case, I would instead use external guides to simulate the hair. this way Normalize can do its job normaly while another set of guides is driving the animation. See https://ephere.com/plugins/autodesk/maya/ornatrix/docs/2/Adopt_External_Guides.html and https://www.youtube.com/watch?v=nl4uuvceV8A and https://www.youtube.com/watch?v=5K_7AoGJ0NE

Jeordanis Figuereo (Product Designer. EPHERE Inc.)

Hi, 

No worries, thanks for help now. The issue here is that this is happening on characters that are not simulated,, not even with an oscillator operator. As I mentioned, they found some value that seemed to work on the normalize, but baking the guides seemed to do the trick.

So for characters we do want to use MOOV with, we bake the guides then add an edit guides node back on with MOOV above that. Seems to work so far?

Thanks