View Full Version : Particles slowing down over time

11 November 2008, 04:17 PM

This seems rather elementary but I can't think of the elegant way of doing this:

I have a pflow that I want to go like this:
constant speed operator -> collision test -> gradual slow down from old speed to new speed.

I know the speed operator is keyable but how do I have it controlled by particle age and not global time?


11 November 2008, 06:33 PM
Elegant way, LOL, I'm sure there is an elegant way but this will work:)

You can do this with the particleFlow Freebies "Stop gradually" operator.

Bring the particles into a new event.
This event contains a stop gradually operator and an age test.

Set the Stop Grad to Stop Time - tick use different stop time - set the timing to whatever you set the age test timing too - adjust the event time (example: if you set it to 50, particles will come to a stop after 50 frames of being in the current event)

In the age test set to the same or close to the frame rate of the Stop Timing, to release the particles to the next event.

Link the Age Test to a new event containing your final speed op.

The only drawback is that you do not have control over the curve.

Example: Max2009

11 November 2008, 07:00 PM
Oh yeah, You could also use a drag spacewarp would give you finer control.

Or box#3 ;)

11 November 2008, 07:08 PM
If the new speed is slower I would also use a drag and a speed test to send it to a new event with the new speed set the same as the speed test.
If the new speed is faster you can speed up the particles with some force like wind and also add the speed test to make it not go any faster then the speed you want.

11 November 2008, 06:35 AM
more options for you, here's a not so elegent but technical approach with scripting...

11 November 2008, 10:04 AM
Wow! Thanks everyone for all the effort involved.

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11 November 2008, 10:04 AM
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