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Vinz9
05-24-2010, 05:07 PM
Hello,

I have some particles born from the collision of other particles, I noticed that for them the creation expressions are not executed. Which is the problem since I defined random scale and id for the instancer.
Any work around? I'm using maya2009 x64 sp1.

Thanks

ps : I wanted to have debris emitted when the foot of a creature touches ground. I had some particles stuck below the foot which serve for the collision event. Will probably try a different setup.

Aikiman
05-25-2010, 09:01 AM
Not sure why Maya is bypassing the creation expressions. One workaround would be to parent emitters to the feet (or extract faces from the bottom of you foot and emit from surface) and use the xform command to get the location of the emitter in Y. When the Y axis reaches a certain threshold ie ground level, then emit particles.

Just an idea.

noticeus
05-25-2010, 09:28 AM
don't use the event editor! you're very limited in what you can achieve!

create collision attributes on your particles and use the emit command in your runtime expression to emit new particles.

with this method you have full control over your emission and which attributes you hand over from one particle system to the other.

Vinz9
05-25-2010, 12:25 PM
Not sure why Maya is bypassing the creation expressions. One workaround would be to parent emitters to the feet (or extract faces from the bottom of you foot and emit from surface) and use the xform command to get the location of the emitter in Y. When the Y axis reaches a certain threshold ie ground level, then emit particles.

Just an idea.

Good idea, that's what I did after posting the topic!

don't use the event editor! you're very limited in what you can achieve!

create collision attributes on your particles and use the emit command in your runtime expression to emit new particles.

with this method you have full control over your emission and which attributes you hand over from one particle system to the other.

I've looked a little into this it opens some possibilities, thanks!

animatedfox
05-25-2010, 01:49 PM
If you parent a roughly foot shaped nurbs sphere to the feet and add a nurbs plane where your ground plane is,
You can use the intersect surfaces command (under Edit Nurbs) to create a curve to emit from...Gives some nice varitation in the emission, as it rolls along the feet.
If you want a surface instead of a curve you can make a planar surface out of the intersection curve.
You sound like you are on your way...but just wanted to put another idea out there.
~Ben

noticeus
05-25-2010, 02:19 PM
on this note you can also use maya toon outline to create a surface for particle emission. just a thought!

Vinz9
05-25-2010, 02:36 PM
Thanks a lot for the other ideas, will probably not need that here, since it's for background animation and I'll use fluids for the foreground, but it's good to know

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