RE: hair dynamics and other oddities

["Kim Aldis" <XSI(at)kim-aldis.co.uk>]

The problem arises because hair hasn’t been given a rest state and it’s behaving this way because you’re probably jumping from a frame late in the animation back to the start frame. (it’s not helped in screen grab by xsi jumping to the end frame before going to the start frame).

 

Do this if you’re rendering or screen grabbing:

 

Go to start frame, clear the cache and reset dynamics. Set caching to write. Now jump to the end frame and let it calculate into the cache. Now set the cache back to write only. You’re good to go.

 

If you’re just playing back just clearing the cache and resetting dynamics is enough.

 

If you want dynamics I’d think about rigging the hair. Possibly something  like a lattice driven by a cloth anim might be enough.

 

 

From: owner-xsi(at)Softimage.COM [mailto:owner-xsi(at)Softimage.COM] On Behalf Of Frank Lenhard
Sent: 19 November 2006 19:41
To: xsi
Subject: hair dynamics and other oddities

 

heya,

i got a nice haircut on the characters head. now i want to apply dynamice and make it move a bit. its nothing fancy, just straight hairs hanging down from the top of the head not touching the shoulders.
i got everything figured out so far but one thing.
when i apply the dynamics and start the caclulation, some hairs left and right of the face pop and position themself a bit further away from the face. the hairs on the backside dont do this. and it destroys my haircut ofcourse.
when i reset the dynamics it jumps back to the old place, but as soon as i press play, whoop, hairs are displaced.
what is causing this? i messed with lots of values, but it seems to be out of control. i just need to press the dynamics button and they pop.

another thing i came across is a problem with the split hair command. it work exactly ONE time, and then never again!
i make a new hair system, brush them to the left and right. checking the Group Id's i see thats all Group 0.
then i select half the bunch and split them. as expected they get into group2 and the rest stays group0. no interpolation.

but as soon as i want to split another bunch, or shatter or do something else, they always revert back to group2. all of them. and when they where in group2 once, they never go back to group0. therefore no way for me to split them again. because split wont do anything any more, but move hairs into group2, which they are all in already :/
and confirmation or workaround for this?


thanks guys!

ciao
franky