How can I decelerate the particles in an emitter independent of the 'birth' speed

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Level 4

1,308 points

How can I decelerate the particles in an emitter independent of the 'birth' speed

As I understand it, the 'speed' setting of the emitter determines the speed of each fresh particle that is birthed...but doesn't regulate the unified speed of all particles at once.

If there is an emitter that produced 1 particle per 30 frames, and the speed was set to reduce by 10 every second..

a particle that was birthed at 50... ..would continue moving at 50 when the next particle is birthed at 40...and that would continue moving at 40 ...while the particle that comes next will move at 30...and so on...so there would be 1 particle going at 50...one at 40..and one at 30...moving across the project....

So due to this..'ramping' and/or keying the speed to decrease in a 360 emitter produces 'rings' ....and in a line..it produced waves of lines...each one moving slower than the one that came before it..

I want to know how to decelerate the actual particles that have been birthed. Just like you would do with an object that has a 'motion path' or 'move' behavior that is set to decelerate.

There are 3 emitters I am trying to do

1 is similar to a fireworks blossom...with a 360 emitter that decelerates

1 is similar to a stream of water coming from a hose...that has a trajectory

1 is similar to a tennis ball launcher..

I have tried the 'gravity' 'wind' and 'attracted to' behaviours...and I get the feeling that I am on the right track...but nothing has been exact enough so far.

Also I have played with 'ramp' for literally hours....but I am convinced it cannot do much other create awesome looking rings...

I want to know if there is a definitive way to achieve this, or should I keep putting in the time with the 'wind' and other simulators?

Or do I just not understand the 'speed' parameter of an emitter as much as I think I do?

iMac (Retina 5K, 27-inch, Late 2015), macOS Sierra (10.12), 8gig ram, amd R9 M390, core 1%

Posted on Jan 9, 2018 2:16 PM

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Answer 1

Top-ranking reply

fox_m

Level 6

13,282 points

Jan 9, 2018 3:36 PM in response to rowie302

Try Simulations > Drag. Increase the Amount until it slows down the particles to the speed you need. You can set an out point to shorten the effect and combine it with Gravity (set an in point a few frames before the end of Drag).

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Answer 2

fox_m

Level 6

13,282 points

Jan 9, 2018 5:31 PM in response to rowie302

If you're doing a jet of water, you shouldn't use drag - only gravity. You might also experiment with Edge Collision (reduce the height slightly and turn of all but the bottom edge). Also, you pretty much want to keep Gravity active till the end. There is also the capability of keyframing the Amount(/Acceleration) of these behaviors to vary their effect over time.

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Answer 3

rowie302 Author

Level 4

1,308 points

Jan 9, 2018 4:36 PM in response to fox_m

Hello Fox_m

I can't thank you enough. I just made more progress in the last 20 minutes than I did over the last 2 days. So, now I can begin to solve the next step..... I have the right emitter motion, but the particles get sliced into segments. I am sure that I can resolve this with enough time and experimentation with the gravity and drag parameters...but before I get started, is there another operation I should include...to get a unified flow that isn't segmented?

I included the extremely rough set up of the behaviours...to show what I have in mind.

Thank you again for taking the time Fox_m

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Answer 4

rowie302 Author

Level 4

1,308 points

Jan 9, 2018 5:36 PM in response to fox_m

Hello Fox_m,

Thank you again sharing your time and expertise. I will work it out as you have recommended.

Cheers!

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