Re: cloth rigging - how to?

["Tim Leydecker" <BauerOink(at)gmx.de>]

> Hey Tim,
> wasnt wondering how to attach deformers to a mesh - thats easy enough.
> its rather how to have them attached to the deformed mesh, and have them
> deform the mesh in turn, without doubling the deformation.

The hands on approach I tried to outline does that,
it´s not a good idea to plot a point of the deformed
mesh and parent the deformer (like a lattice) to that
input (copied to a Null) if you plan to change the source
input anim again but it´s good enough if all you want is
to change something like the general rotation of a
mesh ontop of a sim in a hurry, like in "now".

I´ll also look into Steve´s article and scops today,
having the mixer, corrective shapes and working
out with pointcaches on my plate anyway in general.

Cheers

tim


----- Original Message ----- 
From: "peter boeykens" <peter_b(at)skynet.be>
To: <XSI(at)Softimage.COM>
Sent: Tuesday, September 25, 2007 10:05 PM
Subject: Re: cloth rigging - how to?


I think if you're a smart cookie you can get straight to the
positions of points over time, using the object model.

But each time I needed this its fast enough making a constraint manually or 
even typing a few commands to set it up "en masse".


Hey Tim,
wasnt wondering how to attach deformers to a mesh - thats easy enough.
its rather how to have them attached to the deformed mesh, and have them 
deform the mesh in turn, without doubling the deformation.

looks like expressions on the static kinestate is going to be the way.


 ----- Original Message ----- 
 From: Steven Caron
 To: XSI(at)Softimage.COM
 Sent: Tuesday, September 25, 2007 9:14 PM
 Subject: Re: cloth rigging - how to?


 "No constraints required, no cycles, quite fast."

 without constraints how are you.. "copying translation values" ? and how 
are you "hanging" the deformer on to the null? expressions maybe?

 steven


 On 9/25/07, Tim Leydecker < BauerOink(at)gmx.de> wrote:
   A hands on approach to get a deformer to follow an
   allready animated - or worse - a vertice baked mesh
   is to copy the translation values of one vertice/point
   onto a Locator/Null object (after snapping it to that
   vertice) then "hang" the deformer onto that Null.

   It´ll travel with your simulated mesh (until you change
   the sim obviously) and by that allows "local" deformations
   regardless of stackorder or deformation order.

   No constraints required, no cycles, quite fast.

   Good enough to let´s say, rotate some sim´ed
   mesh with clean values, might even be good
   enough to substract "offset" from "origin" to
   get a "local" effect. Sorry for all those ".",
   can´t put it better, I´m still dizzy from brooding
   over the above the last few, long days. done.

   Cheers

   tim

   P.S: When you guys test Moondust, make sure
   animation plotted to points is _easily editable and
   layerable (time remap, SRT ontop, re-useable).


   ----- Original Message -----
   From: "Steven Caron" <carons(at)gmail.com>
   To: < XSI(at)Softimage.COM>
   Sent: Tuesday, September 25, 2007 8:24 PM
   Subject: Re: cloth rigging - how to?


   > using the static kine state is stable in my experience...here is how 
we
   > have
   > been using it here at blur.
   >
   > http://www.xsi-blog.com/archives/209
   >
   > steven
   >
   > On 9/25/07, peter boeykens <peter_b(at)skynet.be > wrote:
   >>
   >> Hi Ben,
   >> will see if I can get the driven static kinestate to work - the way I
   >> understand you, this should be indeed what I'm after. Hope XSI agrees 
:-)
   >>
   >> Speaking of cloth sims - from what I understand syflex has such a 
thing
   >> as
   >> a
   >> target pose (not initial state!) - the shape a cloth would assume if 
not
   >> under influence of any forces. But not in the XSI implementation :-(
   >> Anyone can confirm this?
   >>
   >> > You have to constrain two things to the cloth:
   >> > 1) Your deformer
   >> > 2) A "base" null that represents the "undeformed" position. When 
the
   >> > deformer hasn't been moved these two things follow the cloth in the
   >> > exact same position.
   >> >
   >> > Then drive the static kinestate of your deformer with the base 
null.
   >> > This will make the deformations relative to the base null rather 
than
   >> > the predeformed position when the operator was applied, which is 
what
   >> > static kinestate is by default. This is analogous to bind pose in
   >> > Maya.
   >> >
   >> > Also I've had luck with copying the cloth mesh and rigging it, then
   >> > using a simple scripted op to do a "blend" between them. You can 
even
   >> > get really fancy and read a weight map if you like.
   >> >
   >> > for each point in position array:
   >> > alpha = weightmap * slider value
   >> > lerp(mesh1.point mesh2.point, alpha)
   >>
   >> what's "lerp"?
   >>
   >> and how can I access a point's weightmap value?
   >> (its probably RTFM - will dig into the scripting reference tomorrow,
   >> sounds
   >> like it can come in handy.)
   >>
   >>
   >>
   >> >
   >> >
   >> > On 9/20/07, peter boeykens <peter_b(at)skynet.be > wrote:
   >> >> trying to find a good workflow for rigging cloth.
   >> >>
   >> >> at the moment I am cage deforming the highres cloth geometry with 
the
   >> >> syflex
   >> >> simulated cloth. Its all good.
   >> >> now Im trying to layer deformations on top of the simulation.
   >> >>
   >> >> What I would like to get now, is a layer of (few) manipulators, 
driven
   >> by
   >> >> the simulated cloth.
   >> >> I guess I'll cluster constrain nulls to the cloth, and then parent 
my
   >> >> manipulators under those nulls - but Im open for other 
suggestions.
   >> With
   >> >> those manipulators I'd like to "sculpt" on top of the simulation.
   >> >>
   >> >> I do not want to simply envelope the highres to the manipulators,
   >> >> since
   >> I
   >> >> wont get the precision I'm getting from the cage. But if I'm
   >> >> enveloping
   >> >> the
   >> >> highres to the manipulators on top of the cage I'l get a "double"
   >> >> deformation.
   >> >>
   >> >> It works fine if the layer of my manipulators is not deformed by 
the
   >> >> cloth,
   >> >> sculpting locally around the default pose of the cloth, but its 
not
   >> >> intuitive at all working that way.
   >> >>
   >> >> Any suggestions how to approach this?
   >> >>
   >> >> ---
   >> >> Unsubscribe? Mail Majordomo(at)Softimage.COM with the following text 
in
   >> >> body:
   >> >> unsubscribe xsi
   >> >>
   >> >
   >> >
   >> > -- 
   >> > -Ben Barker
   >> > ---
   >> > Unsubscribe? Mail Majordomo(at)Softimage.COM with the following text 
in
   >> body:
   >> > unsubscribe xsi
   >>
   >> ---
   >> Unsubscribe? Mail Majordomo(at)Softimage.COM with the following text in
   >> body:
   >> unsubscribe xsi
   >>
   >


   ---
   Unsubscribe? Mail Majordomo(at)Softimage.COM with the following text in 
body:
   unsubscribe xsi




---
Unsubscribe? Mail Majordomo(at)Softimage.COM with the following text in body:
unsubscribe xsi