|
Thanks a lot Juan - that comes very handy for this
one :)
- Morten
----- Original Message -----
Sent: Thursday, March 30, 2006 5:15
PM
Subject: RE: How to control Particle
instance orientation?
hi,
or
try my script.
it
plots curves and optionally creates nulls path-animated on
them.
you
don't have to tag you particles, just select the cloud and run
script.
(and
the curves are nicely put into a hierarchy...)
...quick and clean solution
;-)
(oh,
and dying particles are taken into account)
Juan
-----Original Message-----
From: adrian
[mailto:adrian.wyer(at)fluid-pictures.com]
Sent: 30 March 2006
16:04
To: XSI(at)Softimage.COM
Subject: Re: How to control
Particle instance orientation?
no it doesn't help with orientation, but it
DOES provide a much quicker way of getting paths from particles
Adrian Wyer
Fluid Pictures
----- Original Message -----
Sent: Thursday, March 30, 2006 3:46
PM
Subject: Re: How to control Particle
instance orientation?
I am not sure I follow Adrian - that provides
me with paths, but not the orientation for my fish: I'd have to manually
set paths for them all afterwards no!?
- Morten
----- Original Message -----
Sent: Thursday, March 30, 2006 4:28
PM
Subject: Re: How to control
Particle instance orientation?
enter tag point mode, tag all your
particles on the LAST frame on your animation
hit 'plot->curve'
tada!
a
Adrian Wyer
Fluid Pictures
----- Original Message -----
Sent: Thursday, March 30, 2006
3:21 PM
Subject: Re: How to control
Particle instance orientation?
Problem solved - Kim's mail sparked an
idea in my tired brain.
I tried plotting the particle motion
this morning, using Brads particle plotting tool, but there is no
simple way to control or fix the roll along a swimpath when dealing
with xyz curves :( - so I had almost abandoned that path.
Kims mail made me think it over and I
just thought of converting position curves to Path after plotting the
particle animation, and after removing rotation keyframes and
activating tangency and upvector in the Path Constraint all is good -
only caveat is I have to do that manually, but alas I can select them
all and do it on a multiple ppg. So there is a suggestion for an
improvement on Brads CGS_Plot Particles: plot to path animation with
options for activating tangency and upvector.
Thanks guys - note for Brads Sim thread
on XSIbase: we want better (read full) oriantation control for
particles!
Morten Bartholdy
3D & VFX
Artist
----- Original Message -----
Sent: Thursday, March 30, 2006
3:46 PM
Subject: RE: How to control
Particle instance orientation?
I had to deal with this a year or so
ago. You're right, the particle orientatin will flip. You're also
right about orientation being a problem with deformed
particles.
My solution was to build a scripted
op onto the particles that did the orientation properly, using an up
vector. It wasn't that hard, but then it's only not hard if you have
the relevant skills.
K.
From: owner-xsi(at)Softimage.COM
[mailto:owner-xsi(at)Softimage.COM] On Behalf Of Morten
Bartholdy
Sent: 30-March-2006 14:38
To:
XSI(at)Softimage.COM
Subject: Re: How to control Particle
instance orientation?
Hi Eric,
I suppose you mean deforming the
cloud to get a swimming school of fish rather than use goals!? I
guess it is worth a try, I just see a problem with particle
orientation when the particlecloud is deformed. I don't
recall if there is a script somewhere to fix that.
Morten
----- Original Message -----
Sent: Thursday, March 30,
2006 3:00 PM
Subject: Re: How to control
Particle instance orientation?
Morton,
Have you tried deforming your cloud with a cage deformer or
a lattice instead of directly on a curve?
I usually use a lattice deformed on a curve, it appears
less rigid. Also you can get a lot of nice secondary
anmation by attaching a slow shape jitter or a wave or even
animated cluster centers on point along the curve. I am
not sure what this will do to the up vectors, but I suspect it
might handle it differently. Worth a try.
Eric
Freelance 3-D Animator, F/X Artist
----- Original Message ---- From: Morten
Bartholdy <xsi(at)colorshopvfx.dk> To:
XSI(at)Softimage.COM Sent: Thursday, March 30, 2006 3:17:19
AM Subject: Re: How to control Particle instance
orientation?
Hi Mathieu,
Yes the roll provides active
control - actually if I for instance leave the roll at
90, which should make the fish swim on their side, they flip for
every turn in the goals path, which makes me think there is some
upvector control in play under the hood.
In my test scene I have the goal
following a path which is roughly shaped like an S. For every
turn the particles bank or roll and I have yet to find a way to
avoid or control that precisely. Actually it seems the amount of
roll is not the same for every turn. The trouble is that if I
try controlling it by keyframing the Rotation Velocity Roll, the
fish in the front rolls before the one in the back of the
school, which is why I'd rather find a sort of upvector
contraint.
You can see the problem in this
movie:
Notice how the particles are
actually being orientated with something like an upvector
constraint as the goal takes effect shortly after emission, and
at the right turn they roll almost on their side. This is
directly influenced by the sharpness of the turn on the path, a
bit like the orientation problems when extruding a curveprofile
on a curve.
Any hellp is much
appreciated.
Morten Bartholdy
3D & VFX
Artist
----- Original Message -----
Sent: Wednesday, March
29, 2006 5:30 PM
Subject: RE: How to
control Particle instance orientation?
Doesnt
the roll parameter from the Rotation Velocity control that?
Maybe Im misinterpreting your question but seem to me thats
the control to play with. The other way would be to create a
scripted particle event and control the orientation from a
script. Im not sure if Im being very helpful here so feel free
to elaborate a bit more on the problem if you want more
help.
Mathieu
Leclaire
R&D
Programmer
Hybride
Technologies
-----Original
Message-----
From:
owner-xsi(at)Softimage.COM
[mailto:owner-xsi(at)Softimage.COM]On Behalf Of Morten
Bartholdy
Sent: Wednesday, March
29, 2006 2:35 AM
To:
XSI(at)Softimage.COM
Subject: How to control
Particle instance orientation?
Hi
all,
I am
creating a school of fish using of instances on particles
following a goal, and it is sort of working alright. Problem
is to control the upvector of the instances - the
fish roll on their path when the goal changes direction.
I have Align on velocity on and this is working fine, the
instances direction use rotation, and face direction use
rotation which I am not quite sure has an effect on the
instances, but apart from plotting and controlling the
upvector directly, is there something for controlling the roll
I have missed?
Morten
Bartholdy
3D & VFX Artist
|
