Fun with Particles

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me too have to work early tomorrow….here 2am….
talk later
cya!
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To transfer your velocity attribute from you particles to the spheres you are copying to them you should enable Use Template Point Attributes in the Attribute folder on your Copy SOP. This allows you to transfer specific attributes to the copied geometry. To make use of the velocity in DOPs you need to enable Inherit Velocity from Point Velocity on the RBD object. This will impart the objects in DOPs with the velocity from the spheres.

However, for what you guys are trying to accomplish, emitting rigid body spheres from a particle system, you would probably be better off using the RBD Point Object. I made some changes to the file and attached it.

Instead of copying spheres to the particles and feeding them to DOPs, it takes the particles and instances the sphere onto each one when it is created in DOPs.

I made some changes to the popnet as well. Since in DOPs a gravity force is being applied, the velocity values from POPs aren't translating well to RBD so I increased velocity and added a gravity force. I also added a birth group that will kill off each particle the next frame. This is necessary or each particle will attempt to create a new sphere every frame. The activation is set to $F > 0 so the preroll will still work.

Also, in DOPs I disabled Make Objects Mutual Affectors on the RBD Solver to decrease sim time at the cost of the spheres colliding with each other.

Of course, depending on the situation you might find that just doing collisions using POPs is sufficient.

Attachments:
particles_rbd_point.hipnc (1.4 MB)

Graham Thompson, Technical Artist @ Rockstar Games
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Pretty!
Chris McSpurren
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hey Graham,

its always a pleasure to have a look at your solutions,
i'm glad there are so many helpful people in this forum!

regards,
Manu
http://vimeo.com/user2522760 [vimeo.com]
http://stormbornvfx.com/ [stormbornvfx.com]
Manuel Tausch
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graham

Thanks for explanation…ill work on that and return with it
thanks again
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