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View Full Version : Odd rotation when particles come to a stop.


Leebre
11-06-2004, 04:59 PM
Has anyone ever seen this problem (http://leebert.monkeyfury.com/stuff/st/shooter2_platonics.avi) before? You'll notice that as the particles come to a stop the rotations of the objects go haywire. I'm not doing anything special, just using PGravity to cause the particles to come to a stop. Am I missing something?

Srek
11-06-2004, 05:12 PM
Hi,
seems to me you were giving the particles a spin on collision with the ground.
During movement they only seldom collide, but on standstill they will collide continously with the ground.
Cheers
Srek

Leebre
11-06-2004, 06:21 PM
Yes, I see that I am applying way too much spin at the point of collision. I've managed to make it look more realistic but I've noticed something else now. When the objects collide with the plane they seem to be colliding at their midpoint even though I have an offset specified. It isn't until after the particles come to a rest that they pop up to the offset distance.

Srek
11-06-2004, 06:45 PM
If you ar eusing polygon objects as particles and collider maybe try the geometry option for the collision node.
Cheers
Srek

Leebre
11-07-2004, 03:36 PM
Srek, I would my partcles to have a cwetain amount of spin when they hit the ground and while most of them come to a stop there are a few that keep vibrating. Is there some way for me to force a particle to stop spinning at a certain time?

Srek
11-07-2004, 04:53 PM
Yes of course.
See attached image for an example. It reduces the particles spin by 5% on each frame.
Of course you can simply set it to 0, but this is to aprupt to be usefull in most cases.
Cheers
Srek

Leebre
11-08-2004, 04:18 AM
Hmm...I still get a vibrating movement with some of the particles. If you are interested this is an example file (http://leebert.monkeyfury.com/stuff/c4d/shooter_nostop.c4d).

Srek
11-08-2004, 08:00 AM
How about putting the stopped particles in a different group where you set velocity and spin to zero so they don't move and collisions can't happen anymore.
Cheers
Srek

Leebre
11-08-2004, 01:41 PM
Good idea. I'm currently putting them in a group when they hit the ground so that I can start to decrease their spin at that time. I'll pass them into another group once their velocity nears zero and see what happens. Thanks for the help!

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