Particles that die on contact with a surface ?

# 1 16-03-2008 , 02:17 AM

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Particles that die on contact with a surface ?

Hi everybody

I have a question regarding maya particles.

Ok I have a scene with a swimming fish (my great white shark)
I have created a particle emitter which uses instances of a soft body nurbs sphere to simulate bubbles.

I have placed this just below the camera and parented it to the camera so it will move where the camera moves.

Its to give the impression of somebody breathing underwater.

Ok I have created an expression that will kill any particles that rise above the water line so that maya doesn't get bogged down with tones of geomtry.

Ok the problem is... My camera moves quickly when the shark attacks (camera moves backwards very quickly) and in turn the bubbles get sucked into his mouth. Now I have added the shark geometry to collide with the bubble particles so the bubbles gather inside his mouth as he swims.

Now is there a way or expression I could write that will say to the particles. You must die when you touch this surface ??

I have tried the following to sort this problem out, I have increased the speed of the particles towards the end of the animation so that the particles move up over the snout instead of in his mouth.

Also I have tried adding an air field inside the sharks mouth so that it will blow out the bubbles so they dont get too many.

But is there a way to have the exra particles die on contact with the surface ??

if anybody can help that would be great.

thanks

Andy Gee

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# 2 16-03-2008 , 02:30 AM

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why not create a sphere or other collision object that entirely blocks the shark's mouth, but then hide the object or make it non-renderable?

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# 3 16-03-2008 , 02:39 AM

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Simple solutions

That will work I suppose

I just wanted to know if there was way of killing particles on contact of an object ?

thanks

Andy Gee

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# 4 16-03-2008 , 02:47 AM

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there's gotta be, but i'm gonna assume that some coding might be involved... i haven't tinkered with particles since my particle animation class... that was about 7 or 8 years ago =P

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# 5 16-03-2008 , 02:56 AM

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Check the help under Particle Collision Events to be sure, but I believe that if you create a particle collision event you can just leave the three checkboxes for "Emit" "Split" and "Random # Particles" off.

Then just set the "Num Particles" slider to 0.

Try that, and let us know if it helped at all user added image

Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS
izzylong.com

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# 6 16-03-2008 , 02:56 AM

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Hey Neo Strider

will try your method out

Thanks

Andy Gee

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# 7 16-03-2008 , 03:02 AM

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Hey ragecgi

Will try that out, Just looking at the particle collision event thing.

but not sure how to use it.

Just wanted to ask is there a way to have 2 emitters have 2

particle collision geo connectors for 1 object ??

I know that you can have multiple geo collisons for different

objects in your scene, was wondering if you can do it the other

way, multiple emitters with different collsion states for a single

object ?

thanks

Andy Gee

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# 8 16-03-2008 , 05:28 AM

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Originally posted by Andy Gee
Just looking at the particle collision event thing.....but not sure how to use it.

Originally Posted by

No prob

Find out more about how to use the Particle Collision Event Editor in the help by hitting F1 while in Maya and browsing to:

Using Maya
>Dynamics and Effects
>Particles
-Particle Collisions

There are at least 4 tutorials in there along with the standard help text to help you get what you want user added image

....multiple emitters with different collision states for a single object ?

Originally Posted by

Yep

Automatically when you click "Create New Event" an incremental number value is assigned to the new event, and added to the events list on the right, per particleShape.

You can even assign global procedures/expressions to the events as well, all within the editor.

Good luck, and remember to read all the help regarding the Particle Collision Event Editor, as it helped me to double check my answers here user added image

Good luck!

Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS
izzylong.com

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