Emit particles on time per Point

[Rob P]

Hi,

I have a POP source where points enter and stay but I do not want them to emit constantly.

Is there a way to emit particle only on time when the emitter point enter in the POP ?

 

[Atom]

Sure, just craft an Activation expression (Birth TAB) that matches the frame numbers when your emitter is is the correct location.

For instance, if the emitter is in the correct location from frames 36-96...

if($FF >35 && $FF < 96,1,0)

 

Edited October 26, 2016 by Atom

[Rob P]

Thank you for your reply Atom,

Ok for the expression but that mean that all the emission points will emit particles constantly between Frames 35-96.

However I would like my emission points just emit the first frame they enter in the POPnet. 

[dimovfx]

Emission type -> All Points

then animate Impulse Activation to be "1" at the frame you want to emit particles. or with expression $F==1 (will emit at frame 1 only)

[Rob P]

Thanks for your reply Sasho78, I understand the trick but in my case, my points source are entering in my POPnet at every frames and I want them to generate particles only the first frame when they are in the POPnet so I have to do it in a procedural way and not by specifying a specific frame.

[Daverod]

I am now in the same situation.

In my grid some prims are going from black to red. I want them to emit 100 particles just when they turn red the first time and never again.

Imagine: Two prims turned red and they emitted 100 particles each. I dont want them to keep on emitting despite that some other prims will be turning also red.

 

Did I explained?

 

Thanks in advance.

[kfu]

There is a simple solution to it, just isolate the frame when the attribute changes(Cd in my example file). Depends on your situation you may need modify it to suit your need. 

 

pop.hipnc

[Noobini]

surely you would use the Just Born Group ? To me that would be most simple solution.

So in Birth, enter a group name say, justborn in the Just born Group.

Then 'do something' to the justborn group. Simply add a pop wind, tick group, enter justborn.....adjust wind...you'll see the wind affects the new particles only at the moment they are born and that's it.

(or if you were emitting particles from newly born particles same idea with justborn...but also I'm thinking pop replicate and maybe kill original particle)