Emitting Particles from Layer not working

[Dwayne Neckles]

i found the trapcode forum on this site and will post there..

[Darby Edelen]

[Dwayne Neckles] “I am trying to emit particles from a layer that is 3d and its not working at all..”

This could be any number of issues. If your layer is small then you may need to turn the particles/sec value up very high to see any particles emitted. Also you cannot use a layer that has collapse transformations or continuously rasterize on.

Could you include a screenshot of your timeline and your particular settings?

Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA

[Dwayne Neckles]

Thank you so much for attempting to help me out!!

http://www.dnecklesportfolio.com/transfer/ae/particular1.png
http://www.dnecklesportfolio.com/transfer/ae/Main.mov

Its just really sparse and no where as many particles as in the tutorial

https://trapcode.com/help/particular/layer_emitter.html

[Darby Edelen]

You need to increase the particles per second. My impression of the way that Particular works with layer emitters is it samples the full width and height of the given layer at the particles/sec rate and only emits a particle when there is actually something there in the layer.

So, at 100 particles/sec, Particular checks 100 random points on the (full) layer every second. If there is no pixel information at the point it checks then a particle will not be emitted. So, for example, if you have a layer that is 1000 x 1000 pixels and is mostly transparent but has a 10 x 10 area of white at the center then 99.99% of the particles you think should be emitting do not:

1000 x 1000 layer = 1000000 pixels

10 x 10 layer = 100 pixels

100 pixels / 1000000 pixels = 0.0001 = .01% * 100 particles/sec = .01 particles per second actually emitted

Either reduce the amount of empty space in the pre-comp or increase your particles/sec dramatically!

Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA

[Dwayne Neckles]

DARBY!!!

THANK YOU SO MUCH!

Your analysis was right and your suggestion made a difference..
i just thought particular used only visible party of the comp… not the entire width..I see i was wrong..

thanks again

Dwayne

[Jeremy Allen]

Nice explaination there Darby, I didn’t fully understand how that worked either..

On a related note, do you know how velocity and gravity affect particles emitted from a layer? I was trying to do a different version of the popular “text to smoke” effects, only using pictures instead of text and a different kind of particle (same basic principle though). Once my particles were built up, I wanted to blow them towards the camera with a mix of velocity and z wind. From what I could gather, it seemed like only newly generated particles were affected by the wind and velocity, while older particles just died out in the position they were in.

Is this normal, or was I doing something wrong? Basically I wanted all the particles to start blowing once I keyframed the wind and velocity..