View Full Version : Particle collision problem

03 March 2009, 12:22 PM
Hi guys,

I have created a particle system for a simple animation. However, a problem occurs when the particles collide with a deflector, after the collision there is slight offset of each particle. Any ideas how I can fix it? File can be download from HERE (

Thank you

03 March 2009, 10:01 PM
Use light text :)

Well it has to move in order to register the collision AFAIK. The amount of movement is quite small. If you notice the movement follows the shape of the spherical deflector you are using. So is the a way to fix it? Store the particle position and id and use that information when a particle gets to the new event. Script it or use a box#3 op.

03 March 2009, 09:34 AM
Making the integration step smaller might help, depending on how precise you really need it to be.

03 March 2009, 06:05 PM
Nooch, haha, that is the first thing I checked :) It seems to be directly related to the deflector collision registration, the particles move 0.01 of a unit upon collision and in the direction/shape of the deflector. It is a miniscule amount but they do move. They only fix I can think of is to just move them back to their original location.:shrug:

03 March 2009, 04:33 AM
The effect is due to the option "Continue" for Collides. This is to ensure that the particles gets to the other side of the fence upon collision and is able to continue its movement without interlocking with the deflector. Try "Stop" option and see what happens.

Oleg B.

03 March 2009, 03:42 PM
Now you are making me think I'm crazy...Still moves :(

03 March 2009, 09:13 PM
Thanks for all advice. I managed to fix it when I used inside Collision Test "Will Collide = 0" inset of "Collides = Continue". Works fine so far.

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03 March 2009, 09:13 PM
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