flow particles around moving surface

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Kris Rivel

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Sep 12, 2013, 9:51:02 AM9/12/13
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I have a character walking around that has flocking particles flowing around the mesh.  It looks great...but when the character moves, the particles "slide" to the back...responding I guess to the mesh/bodies momentum forward.  Is there any way to prevent that?  I want them to flow around but not respond to the mesh's movement in space.  I'm  using a get closest location, get point and particle position, into a linear interpolate then into a set particle position...with an align to surface to handle the up vector.  Any ideas?  

Kris

Christian Freisleder

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Sep 12, 2013, 10:29:29 AM9/12/13
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hey Kris,
if it is a simulated ice tree you could get the closest location on
the previous frame and the current frame, subtract the pointpositions
from each other and add this vector to your current point pos. Now do a
new closest location search with the new pos vector as an input and you
should have a compensation for your momentum on a per point basis.
Not sure it works though.
hope that helps.

christian

Kris Rivel

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Sep 12, 2013, 12:05:35 PM9/12/13
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Thanks...trying that and it doesn't seem to work...maybe I'm not doing it properly :-/

Kris Rivel

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Sep 12, 2013, 12:22:03 PM9/12/13
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BTW...I should clarify...I don't want the particles to go "around...avoid" the mesh...they are flowing ON the mesh.

olivier jeannel

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Sep 12, 2013, 12:45:36 PM9/12/13
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Hi Kris,

This is from another subject on the list . I can't recall the exact title, but it was about strands flowing on deformed geometry.
Here's  a scene with strands  flowing  on a deformed mesh.
https://www.dropbox.com/s/ac7p42bs8qzoelk/StrandDeform_Location.rar

Hi Eduardo,
Lucky you I kept the files :D
Here is a rar file with 3 different scenes. The most elaborate with animation Location is the one named "StrandDeform_Location".
The 2 others were tests made by me.

Cheers,

Olivier


Le 08/05/2013 15:14, Eduardo Andrade a écrit :
Hi Olivier,

How are you doing? My name is Eduardo and I'm from Brazil. I was looking for on the internet about stick strands in a geometry animation and I found you thread on the softimage list. I saw that Edy shown a great solution about this problem and provided a link with the file scene, but the link is broken. So, I would like to know if you could send it to me. Thanks in advance.

Cheers,

Eduardo

Kris Rivel

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Sep 12, 2013, 12:58:29 PM9/12/13
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Thanks Olivier!!  This makes them stick great and follow the animated mesh...but...my flocking simulation I had on my particles is gone...they're basically stuck in place.  Any suggestions?

olivier jeannel

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Sep 12, 2013, 2:05:35 PM9/12/13
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On top of my head, if your flocking is velocity based you could try something like this :

Maybe the GetClosestLocation could be replaced with something more elaborated :/

Scene is here, scrub the time line it's "velocited" and follows deformation :
https://www.dropbox.com/s/8k96t7bxkwtv8y0/Velocity_Reinterpret.scn

Kris Rivel

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Sep 12, 2013, 2:28:16 PM9/12/13
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Actually...got your strand version working.  Just re-ordered a node or two and it works great.  Now I just need to introduce a blend as the particle start off on one shape, then move to this one...that "shouldn't" be too tough.  This new demo scene is great but when I apply it, the particle seem to slow down or stop their flocking when the character moves...but they do stick!...just wanted you to know.  I really appreciate it!

Kris
dddidiff.png

olivier jeannel

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Sep 12, 2013, 2:31:18 PM9/12/13
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Well I just replayed the scene again and it's not so good, I admit... It's sliding a bit with violent mouvement..




Le 12/09/2013 20:05, olivier jeannel a écrit :
On top of my head, if your flocking is velocity based you could try something like this :

olivier jeannel

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Sep 12, 2013, 2:41:52 PM9/12/13
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Happy I could help :)
I found the reinterpret location working nice when the object is rotating, you can see it's not sliding.
Finally I wonder if the defaut I found was not just because of the Turbulize velocity that tends to coagulate a bit).



Le 12/09/2013 20:28, Kris Rivel a écrit :
Actually...got your strand version working.  Just re-ordered a node or two and it works great.  Now I just need to introduce a blend as the particle start off on one shape, then move to this one...that "shouldn't" be too tough.  This new demo scene is great but when I apply it, the particle seem to slow down or stop their flocking when the character moves...but they do stick!...just wanted you to know.  I really appreciate it!

Kris
On Thu, Sep 12, 2013 at 2:05 PM, olivier jeannel <olivier...@noos.fr> wrote:
On top of my head, if your flocking is velocity based you could try something like this :

Maybe the GetClosestLocation could be replaced with something more elaborated :/

Scene is here, scrub the time line it's "velocited" and follows deformation :
https://www.dropbox.com/s/8k96t7bxkwtv8y0/Velocity_Reinterpret.scn












Le 12/09/2013 18:58, Kris Rivel a écrit :

Kris Rivel

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Sep 12, 2013, 3:40:32 PM9/12/13
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Yeah really appreciate it.  I'll send back a test scene so you can see what I changed...works really nice now...thanks!

Gerbrand Nel

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Sep 13, 2013, 3:53:47 AM9/13/13
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Hey list
I have this irritating problem, and I was hoping you guys knew what
might cause it, and how to fix it.
I've rigged this character, and the interaction is a bit weird.
When I navigate around the geometry, everything is real time.
When I select a part of the rig and start transforming, there is a few
seconds of "dead softimage" and then it wakes up and works in real time
again.
This happens every time I start transforming on a new axis.
Any ideas?
Thanks people :)
G

wavo

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Sep 13, 2013, 4:15:49 AM9/13/13
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Noo!  (...only if it has  a lot of polygons),

do you use linked shapeanimation or is it subdivided, is the delay  in camera-view or in every view?!

Did you merge it in a new Scene?!
Wireframe or shaded, heavy geo?!

W
--


Walter Volbers
Senior Animator

FIFTYEIGHT 3D
Animation & Digital Effects GmbH

Kontorhaus Osthafen
Lindleystraße 12
60314 Frankfurt am Main
Germany

Telefon +49 (0) 69.48 000 55.50
Telefax +49 (0) 69.48 000 55.15


mailto:wa...@fiftyeight.com
http://www.fiftyeight.com


--------------------------------------------------------
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Eine Kooperation der escape GmbH und der FIFTYEIGHT3D GmbH

http://www.ESC58.de

Matt Morris

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Sep 13, 2013, 4:34:13 AM9/13/13
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Are you referencing the mesh in ice at all? I've found that can cause delays sometimes.

Gerbrand Nel

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Sep 13, 2013, 4:55:04 AM9/13/13
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It happens on all views, shaded and wireframe.
I'm emitting particles and strands on the mesh, but its all hidden.
I tried the merge into new scene, but I still have the lag.
This is 2013 btw.. I'll check 2014, but we cant move the project there for now :(
I was hoping there was a display setting I was missing.

Thanks for the input guys
G

wavo

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Sep 13, 2013, 5:10:40 AM9/13/13
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... in case that  the character has more than one deformer (e.g. shape envelope push etc. )
 turn it of step by step to see where is the vault
sorry, i would also delete the particlestuff only to expulse!

but i guess you checked this already

W

Martin

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Sep 13, 2013, 5:14:40 AM9/13/13
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Any broken links? I had some delays working with broken Synoptics. Nothing like this though.

Martin

pet...@skynet.be

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Sep 13, 2013, 5:47:24 AM9/13/13
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hiding the particles and strands is not going to simulate them but that doesn’t mean the ICE tree is totally inactive.
such a lag on every single interaction with a geometry sounds *exactly* like what I’d expect from a hidden ICE tree.
it’s traversing the tree to see if everything’s hooked up properly (the lag) and then does nothing with it (fast interaction) – which is not ideal.
 
try to break the link with the mesh in the ICE tree by pointing to some other geo that you’re doing nothing with – I’d bet the lag is gone.
 
in more complex trees I try to make it easy to switch the input geometry – such as avoiding several getters pointing to the same geometry, and putting a passthrough between the getter and the rest of the tree. Or use a group as input (if possible) and remove/add the mesh from the group as needed – without having to go in the ICE tree.

olivier jeannel

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Sep 13, 2013, 6:22:58 AM9/13/13
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I had massive slowdown with getting 150 Matrices in a hierarchy because of 4 unfrozen Center operators in the modeling stack. :/

Gerbrand Nel

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Sep 13, 2013, 6:30:10 AM9/13/13
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Yup. it was my ICE trees
Thanks guys
G

julien carmagnac

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Sep 13, 2013, 7:47:26 AM9/13/13
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Hello list,

And do you know what is going wrong in your ICE (If you think that's an anormal behavior) ?

I already have interaction lag with ICE tree and I find that's due to the use of group in ICE Tree.
I've post this on si-community http://www.si-community.com/community/viewtopic.php?f=15&t=3009&hilit=+group+ICE+lag
Just curious to know if your problem is similar.

Thanks.


2013/9/13 Gerbrand Nel <nag...@gmail.com>

Gerbrand Nel

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Sep 13, 2013, 8:47:40 AM9/13/13
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I do have groups of curves defining a vector field on the mesh, so it might be that :)
G

On 2013/09/13 01:47 PM, julien carmagnac wrote:
Hello list,

And do you know what is going wrong in your ICE (If you think that's an anormal behavior) ?

I already have interaction lag with ICE tree and I find that's due to the use of group in ICE Tree.
I've post this on si-community http://www.si-community.com/community/viewtopic.php?f=15&t=3009&hilit=+group+ICE+lag
Just curious to know if your problem is similar.

Thanks.


2013/9/13 Gerbrand Nel <nag...@gmail.com>
Yup. it was my ICE trees
Thanks guys
G

On 2013/09/13 12:22 PM, olivier jeannel wrote:
I had massive slowdown with getting 150 Matrices in a hierarchy because of 4 unfrozen Center operators in the modeling stack. :/


Le 13/09/2013 11:47, pet...@skynet.be a �crit�:
hiding the particles and strands is not going to simulate them but that doesn�t mean the ICE tree is totally inactive.
such a lag on every single interaction with a geometry sounds *exactly* like what I�d expect from a hidden ICE tree.
it�s traversing the tree to see if everything�s hooked up properly (the lag) and then does nothing with it (fast interaction) � which is not ideal.
�
try to break the link with the mesh in the ICE tree by pointing to some other geo that you�re doing nothing with � I�d bet the lag is gone.
�
in more complex trees I try to make it easy to switch the input geometry � such as avoiding several getters pointing to the same geometry, and putting a passthrough between the getter and the rest of the tree. Or use a group as input (if possible) and remove/add the mesh from the group as needed � without having to go in the ICE tree.
�
Sent: Friday, September 13, 2013 10:55 AM
Subject: Re: interaction lag
�
It happens on all views, shaded and wireframe.
I'm emitting particles and strands on the mesh, but its all hidden.
I tried the merge into new scene, but I still have the lag.
This is 2013 btw.. I'll check 2014, but we cant move the project there for now :(
I was hoping there was a display setting I was missing.

Thanks for the input guys
G
On 2013/09/13 10:34 AM, Matt Morris wrote:
Are you referencing the mesh in ice at all? I've found that can cause delays sometimes.
On 13 September 2013 09:15, wavo <wa...@fiftyeight.com> wrote:
Noo!� (...only if it has� a lot of polygons),

do you use linked shapeanimation or is it subdivided, is the delay� in camera-view or in every view?!


Did you merge it in a new Scene?!
Wireframe or shaded, heavy geo?!

W


Am 9/13/2013 9:53 AM, schrieb Gerbrand Nel:
Hey list
I have this irritating problem, and I was hoping you guys knew what might cause it, and how to fix it.
I've rigged this character, and the interaction is a bit weird.
When I navigate around the geometry, everything is real time.
When I select a part of the rig and start transforming, there is a few seconds of "dead softimage" and then it wakes up and works in real time again.
This happens every time I start transforming on a new axis.
Any ideas?
Thanks people :)
G



--


Walter Volbers
Senior Animator

FIFTYEIGHT 3D
Animation & Digital Effects GmbH

Kontorhaus Osthafen
Lindleystra�e 12

60314 Frankfurt am Main
Germany

Telefon +49 (0) 69.48 000 55.50
Telefax +49 (0) 69.48 000 55.15


--------------------------------------------------------
ESC58
Eine Kooperation der escape GmbH und der FIFTYEIGHT3D GmbH

http://www.ESC58.de



�
--
www.matinai.com





julien carmagnac

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Sep 13, 2013, 9:08:13 AM9/13/13
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Ok Thanks for you return Nel,

I suggest you to put many "Instance Shape" than curve and use a build array node to get all.

In any case
I'm glad to not be the only one with this problem (sorry ;) ).
If anyone here seen this problem and is on the beta, maybe he can report it to Autodesk?

Friendly.


2013/9/13 Gerbrand Nel <nag...@gmail.com>
I do have groups of curves defining a vector field on the mesh, so it might be that :)
G

On 2013/09/13 01:47 PM, julien carmagnac wrote:
Hello list,

And do you know what is going wrong in your ICE (If you think that's an anormal behavior) ?

I already have interaction lag with ICE tree and I find that's due to the use of group in ICE Tree.
I've post this on si-community http://www.si-community.com/community/viewtopic.php?f=15&t=3009&hilit=+group+ICE+lag
Just curious to know if your problem is similar.

Thanks.


2013/9/13 Gerbrand Nel <nag...@gmail.com>
Yup. it was my ICE trees
Thanks guys
G

On 2013/09/13 12:22 PM, olivier jeannel wrote:
I had massive slowdown with getting 150 Matrices in a hierarchy because of 4 unfrozen Center operators in the modeling stack. :/


Le 13/09/2013 11:47, pet...@skynet.be a écrit :
hiding the particles and strands is not going to simulate them but that doesn’t mean the ICE tree is totally inactive.
such a lag on every single interaction with a geometry sounds *exactly* like what I’d expect from a hidden ICE tree.
it’s traversing the tree to see if everything’s hooked up properly (the lag) and then does nothing with it (fast interaction) – which is not ideal.
 
try to break the link with the mesh in the ICE tree by pointing to some other geo that you’re doing nothing with – I’d bet the lag is gone.
 
in more complex trees I try to make it easy to switch the input geometry – such as avoiding several getters pointing to the same geometry, and putting a passthrough between the getter and the rest of the tree. Or use a group as input (if possible) and remove/add the mesh from the group as needed – without having to go in the ICE tree.
 
Sent: Friday, September 13, 2013 10:55 AM
Subject: Re: interaction lag
 
It happens on all views, shaded and wireframe.
I'm emitting particles and strands on the mesh, but its all hidden.
I tried the merge into new scene, but I still have the lag.
This is 2013 btw.. I'll check 2014, but we cant move the project there for now :(
I was hoping there was a display setting I was missing.

Thanks for the input guys
G
On 2013/09/13 10:34 AM, Matt Morris wrote:
Are you referencing the mesh in ice at all? I've found that can cause delays sometimes.
On 13 September 2013 09:15, wavo <wa...@fiftyeight.com> wrote:
Noo!  (...only if it has  a lot of polygons),

do you use linked shapeanimation or is it subdivided, is the delay  in camera-view or in every view?!


Did you merge it in a new Scene?!
Wireframe or shaded, heavy geo?!

W


Am 9/13/2013 9:53 AM, schrieb Gerbrand Nel:
Hey list
I have this irritating problem, and I was hoping you guys knew what might cause it, and how to fix it.
I've rigged this character, and the interaction is a bit weird.
When I navigate around the geometry, everything is real time.
When I select a part of the rig and start transforming, there is a few seconds of "dead softimage" and then it wakes up and works in real time again.
This happens every time I start transforming on a new axis.
Any ideas?
Thanks people :)
G



--


Walter Volbers
Senior Animator

FIFTYEIGHT 3D
Animation & Digital Effects GmbH

Kontorhaus Osthafen
Lindleystraße 12

60314 Frankfurt am Main
Germany

Telefon +49 (0) 69.48 000 55.50
Telefax +49 (0) 69.48 000 55.15


--------------------------------------------------------
ESC58
Eine Kooperation der escape GmbH und der FIFTYEIGHT3D GmbH

http://www.ESC58.de

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