### Deforming Geometry with Moving Particles Conforming to Surface

5523   4   0
Member
45 posts
Joined: 3月 2017
Offline
So the title pretty much sums up what I'm trying to achieve but I am finding myself stuck.

I understand how to attach points/particles to deforming geometry using Attribinterpolate node but the points must be static(not moving)from what I understand.

Basically I am trying to do something similar to this https://vimeo.com/210226436 [vimeo.com] but having the torus deforming/animated.
Member
28 posts
Joined: 4月 2017
Offline
Hi chanson78,

Have you tried to use the “point deform” node? I haven't done the tutorial so I'm not sure if it will work but you can try it.

Here is a file of simple setup of the point deform:

Maybe you can do your point/particle animation on the static mesh and use the point deform to follow the animated torus.

Let me know if it works.

Attachments:
pointDeform.hiplc (175.6 KB)

Member
8724 posts
Joined: 7月 2007
Offline
chanson78
I understand how to attach points/particles to deforming geometry using Attribinterpolate node but the points must be static(not moving)from what I understand.

points don't have to be static, you can update primuv attributes using ray sop minimum distance
Ray SOP
- input1: animated points following static rest geo
- input2: static rest geo
- method: Minimum Distance
- check Prim Num and Prim UVW Attribute checkboxes and name your attibutes

Attribute interpolate
- input1: ray sop from above
- input2: deforming geo
- put your Prim Num and Prim UVW attribute names into Element Number and UVW Attribute parms

alternatively you can use VEX using xyzdist() and primuv() functions to replace ray and attribinterpolate for simple or more specific cases
Edited by tamte - 2019年5月14日 14:17:12
Tomas Slancik
FX Supervisor
Method Studios, NY
Member
648 posts
Joined: 7月 2005
Offline
see attached,
direct sampling of deformation using ray sop.
exploits the unrollable torus though.

Attachments:
uvlookup.hiplc (319.8 KB)

Member
1766 posts
Joined: 5月 2006
Offline
Here's a few different methods:

http://www.tokeru.com/cgwiki/index.php?title=HoudiniDops#Pop_stick_to_surface [www.tokeru.com]