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Wopmay
09-30-2008, 09:25 PM
Hi. Can anyone please help me figure out how to prevent dynamic objects from endlessly moving long after they should have stopped?

Specifically, I have a glass window pane that shatters into pieces that then crash to the floor. It looks great except no matter what I try, the pieces continue to wiggle around on the floor forever. Or -- they hit the floor and freeze, which doesn't work either.

What am I missing?

Thanks.

W

Dirk
10-01-2008, 02:08 AM
What settings do You use for the floor collision object?

Surrealist.
10-01-2008, 02:13 AM
Have you tried "stop by stabilizer"?

Wopmay
10-01-2008, 10:59 AM
What settings do You use for the floor collision object?

Sure. These are close to the default values. It seems that no matter what I do, the parts never settle. Changing rotation settings in the glass reduces it but then the pieces fail to fall over.

Any ideas would be greatly appreciated.

Wopmay
10-01-2008, 11:01 AM
Have you tried "stop by stabilizer"?

No. I saw that but --- What is the stabilizer? Where do I get one? Is it expensive? :-)

Surrealist.
10-01-2008, 10:15 PM
LOL! It is just a setting.(Stabilizer being most likely the thing the object is hitting) Usually stops the endless bouncing around.

Wopmay
10-02-2008, 10:50 AM
Thanks. I tried your suggestion of Stop by Stabilizer but no relief. These things just keep hopping around like Mexican Jumping Beans.

Any other ideas?

Dirk
10-03-2008, 04:52 AM
Have You tried Sticky instead of bounce for the collision plane?

zippitt
10-03-2008, 09:49 AM
If you selected the option stop by stabilizer on the collision tab of the glass object it should stop wiggling. I have this problem many times. It sounds like you already tried that though.

If your gravity is really high try tweaking it to see if things stop jumping so much.

Wopmay
10-03-2008, 10:21 AM
Okay. Two good suggestion, less gravity and sticky surface. I'll give then a try. Right now, I have to undo some "refinement" of the glass pieces. I've made the mesh a little too accurate. It's taking forever to calculate.

W

jaxtone
10-03-2008, 12:56 PM
Wopmany!

Now itīs hard to say since you only posted an image of the planes properties!
It could be good to know the glass pieces properties as well to get the whole picture so to say!

One thing you could try is to increase the friction power a little bit, try to change it 20 units at a time so you can see the difference. The Bounce/Bind Power could be a little bit lower but its hard to say as long as the settings for the glass is hidden.

Wopmay
10-04-2008, 06:31 PM
Jaxtone!

Here you are.

This is what I have at the moment. Works a little better. But still wiggles around. Some of the pieces never fall over.

After days of fiddling I'm beginning to think the best thing to do is shorten the shot. Not the best solution, though.

Sticky surface didn't change much, by the way.

What to do? Actually go in and key frame each piece at the end?

Thanks

Surrealist.
10-05-2008, 01:50 AM
You can also make another collision object and set it to event then on the dynamic object you can set it to stop by event. Simply animate the event through the pieces and they'll stop.

What is the shot for? What has to happen? I would be thinking editing at this point for sure.

Ztreem
10-05-2008, 07:55 AM
I wouldn't recomend to have any roughness on the collision object as it makes it harder for the pieces to come to a stop.

stevecullum
10-05-2008, 08:21 AM
Perhaps you should try the ODE dynamics plugin...seems to give better results.

http://www.newtek.com/forums/showthread.php?t=81376

serge
10-05-2008, 09:15 AM
Perhaps you should try the ODE dynamics plugin...seems to give better results.
It will definitely give better results, but it'll be tedious to setup since ODEfl doesn't know 'parts'. So, each piece has to be a separate object for which you have to apply the plugin (unless many of the objects are similar, so you can clone). And if you want to tweak the settings you'd have to go through each object.

With that said, I'd still choose ODEfl over HardFX for this scene :). ("Stop by stabilizer" sucks.)

Wopmay
10-05-2008, 11:08 AM
You can also make another collision object and set it to event then on the dynamic object you can set it to stop by event. Simply animate the event through the pieces and they'll stop.



Thanks, Surrealist, I'll try the Event object as well.

This is only a test. The real scene has a lot of other things going on so maybe the glass will get lost in the confusion.


I wouldn't recomend to have any roughness on the collision object as it makes it harder for the pieces to come to a stop.

Okay. Good tip. I'll see what happens.


Perhaps you should try the ODE dynamics plugin...seems to give better results.

http://www.newtek.com/forums/showthread.php?t=81376

Looks good but Windows only so far.

Thanks to all who helped. While there doesn't seem to be a magic bullet here, at least I figure there isn't some secret button I'm overlooking. I'm going to assume the calculation is only an estimation and good only up to a point.

W

Surrealist.
10-05-2008, 11:53 AM
Take a look here (http://www.newtek.com/forums/showthread.php?t=89863) and maybe he can give you some tips.

serge
10-05-2008, 12:09 PM
...I'd still choose ODEfl over HardFX for this scene ...
I have to take that back. ODEfl also has "start by collision", but, unlike HardFX, the glass pieces will move immediately because they touch the pieces right next to them.

Surrealist.
10-05-2008, 12:11 PM
Also if it is an action sequence a cutaway would get you out of it and you could cut back to the pieces all stopped.

serge
10-05-2008, 12:23 PM
Also if it is an action sequence a cutaway would get you out of it and you could cut back to the pieces all stopped.
Indeed. This is probably the best 'workaround'.

Dirk
10-05-2008, 05:27 PM
Hey Wopmay,

hope this helps:

http://www.newtek.com/forums/showthread.php?p=761198#post761198

Wopmay
10-14-2008, 08:18 PM
Hey Wopmay,

hope this helps:

http://www.newtek.com/forums/showthread.php?p=761198#post761198

Sorry to drop the thread. Had to pay the rent, you know.

Anyway.

Now I'm laughing my tush off. Following your suggestion, I turned off gravity when the pieces began to settle down and they do exactly what I'd expect them to do -- float away.

:D

Must be doing something wrong. Will re-investigate your method when I get my brain wrapped around this scene again.

W

ivanze
10-14-2008, 08:24 PM
That's what happened to me. They look like if they were outerspace. :)

Surrealist.
10-15-2008, 03:08 AM
That is picked up in the other thread with some more settings and sample scenes.

Castius
10-15-2008, 03:55 AM
Turn up your rotation spin resistance. You can also mess with some torque setting to try to reduce some rotation that way as well..

Red_Oddity
10-15-2008, 04:28 AM
It's a shame LWs HBDs need such crude hacks and still don't look 'right', not like shattering something with NRB, Bullet or PhysBam.
Ahwell, everything in time, i guess we'll get some proper (supported) HBD engine implementation from NT someday.

Until then, i do my HBDs in Maya and export it back to LW.

Dirk
10-15-2008, 05:14 AM
Must be doing something wrong. Will re-investigate your method when I get my brain wrapped around this scene again.

W

You turn the gravity off in one frame -that's not going to work, since the parts need to lose their movement energy. Try an envelope that turns down gravity in 10 to 20 frames.

If Your collision object's bounce setting is higher than 100%, give that an envelope, too, and bring it down to 100%. Do this some frames before you turn gravity off.

One more option is to use a wind effector set to "drag". If it shall affect the whole scene, set it to "no Falloff". Give it an envelope, too. There is an example scene in the other thread.

Wopmay
10-15-2008, 10:50 AM
Turn up your rotation spin resistance. You can also mess with some torque setting to try to reduce some rotation that way as well..

Thanks. I'll try that.

erikals
03-19-2009, 09:49 AM
hi, fast question here,
does anyone know if it support parts? so that i can make 40 objects collide at once?
or does each object have to be assigned a setting?