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View Full Version : Particles Keep resetting to 0 !!! what up??



jdjd
08-19-2009, 11:20 AM
Hi gang!
weird thing, not very versed on particles.... maybe ya'll can help.

Landscape scene - 7 vehicles running across landscape. Each has a parented (to each vehicle) particle emitting Null under the front axle to provide road dust. Emission is based on speed. Works great for a while, then randomly LW resets each of the emitters back to 0 particles. No particles emit. Have to reset particle count in each emitter to get them to reappear. Rinse repeat.
Particle settings Lifespan=180 Total particle count = 5000

Have saved scene under new name, saved all objects, etc. etc.

Seems to happen after a F9 render alot, but not specifically that, sometimes just scrubbing the timeline and poof, all emitters reset to 0 particles. (no envelope on channel, but will try that next)

When the particles are there, looks good, life is good. Shows all particles through whole scene, F9 render or Viper shows up pretty.
what up? any ideas?


thanks mucho mucho!
jd

4dartist
08-19-2009, 12:44 PM
I'm going to blame it on Generate by [Speed]. Considering it varies the Birth Rate based on the objects speed. So if the object stops the Birth Rate would be 0. There may be a problem with it causing the number to stick as the base number.. *shrug*. Either way, you should consider using [Sec] or [Frame].

If your car slows down or speeds up and you want your emitting particle amounts to change with it you can still use [Sec] or [Frame] but hit the E for envelope and set some keys up.

I know it doesn't fix your issue, but it may be a work around that lets you finish the animation.

SpawnSP
08-19-2009, 02:23 PM
You can try to save the particles to a .pfx file when they are OK (i think you have to save every emitter). Then the particle generator will stop to calculate them and use the particles stored on the motion file. In this case, I think that particles shouldn't disappear at all.

4dartist
08-19-2009, 02:30 PM
Yep I think that would work too, but then any changes you want to make you need to resave the particle file. Also make sure you put the current frame slider to the last frame, the .pfx file will go to the frame you are on and not beyond. (I think..)

jdjd
08-20-2009, 08:23 AM
Hey gang!
got my particle #'s by Speed working.
Just setting the appropriate numbers in each emitter THEN applying envelope (even tho I am not changing the amount over time) seems to have done the trick... I think you were right 4d in that LW is overriding my numbers when speed = 0.

All is good now, my lil desert truckies are billowing dust like mad.
thanks gang!
jd