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Amhras
07-14-2009, 12:07 PM
Okay, I've got my debris objects driven by a particle system, that works great. I have the ground collision working. Now the problem is getting my debris objects not just to spin, but to stop spinning when they hit the ground.

I tried using the "Random Scale and Rotation" in the dynamics panel of the particle emitter, which works great while the debris is in motion, but when the debris comes to rest the objects are still spinning like out of control buzzsaws. Any ideas of how I can do this without having to hand key over 100 objects? Been trying everything I can think of, but thus far no luck.

DBMiller
07-14-2009, 01:33 PM
If you don't have one already, you will probably need a collision plain with high friction for the debris to catch hold of.

Amhras
07-14-2009, 02:53 PM
I do have a collision plain set up, tried with both the Friction and Fix params at ridiculously high levels. Neither parameter effects the rotation, only position.

Mr Rid
07-14-2009, 05:49 PM
Afraid this PFX approach will not yield anything convincing for what it sounds like you are trying to do. The last time I tried this, when the particles touch a collision ground they suddenly pop to their default 0,0,0 rotation, then spin in wacky ways. Particles laying on a collision ground set to 'bounce' will never come to rest. Have you considered HardFX pieces instead?

Amhras
07-15-2009, 04:03 PM
The hardFX works pretty good(Tho making so many copys manually is a bit of a pain in the butt) but I'm still left with the problem that the debris never comes to rest. They continually vibrate on the collision plane.... Any idea how to lock them down?

Mr Rid
07-15-2009, 04:38 PM
The hardFX works pretty good(Tho making so many copys manually is a bit of a pain in the butt) but I'm still left with the problem that the debris never comes to rest. They continually vibrate on the collision plane.... Any idea how to lock them down?

Um... use Maya? :) Jittery dynamics can be a big problem in LW. Under Collision tab, be sure you have 'Stop by Stabilizer,' selected. In the FX_Browser menu, under Option, adjusting the resolution may or may not make a difference depending on your particular set up.

wildr3d
07-15-2009, 05:00 PM
Try looking through this thread, Dirk has some excellent examples of achieving stable hardfx sims.

http://newtek.com/forums/showthread.php?t=89874

bazsa73
07-16-2009, 12:58 AM
Yes, the good old friction ploy.
Maybe you could try editFx, a bit lame but you shall see.

prometheus
07-20-2009, 08:44 AM
I wonder if anyone has tried out using houdini apprenticeīs new dynamics.

I did some test sometime ago crackin up some boxes and simulated the
dynamics in houdini and then exported the sim out to mdd and it worked fine
to import in lightwave as I recall...and the houdini sims are way more realistic
and comes to rest in a natural way.

I havent had the time to test it anymore so far, once I get the time and
a new computer up and running I would love to try the new ODE dynamics in houdini and see if it exports properly to lightwave through mdd.

http://www.youtube.com/watch?v=1gkk9zQFr3Q

Michael

dandeentremont
07-21-2009, 10:03 AM
I wonder if anyone has tried out using houdini apprenticeīs new dynamics.

I did some test sometime ago crackin up some boxes and simulated the
dynamics in houdini and then exported the sim out to mdd and it worked fine
to import in lightwave as I recall...and the houdini sims are way more realistic
and comes to rest in a natural way.

I havent had the time to test it anymore so far, once I get the time and
a new computer up and running I would love to try the new ODE dynamics in houdini and see if it exports properly to lightwave through mdd.

http://www.youtube.com/watch?v=1gkk9zQFr3Q

Michael

MMMM.... Donuts....

joelaff
07-21-2009, 12:26 PM
Friction will get you most of the way there. Adjust the friction for both the plane and the debris. Use very low roughness values as well.

But to get it all the way stopped you can use DPKit's BDD player with the time remapping feature to bring your BDD data to a halt. Note that you might want to calc at a higher frame rate and then speed it up in BDD PLayer so that you have more actually calculated samples when you begin to slow things down.

prometheus
07-21-2009, 01:16 PM
Donīt know if itīs the donuts or houdini that makes me drool arghh..

houdini 10 smashing good time
http://www.youtube.com/watch?v=S-BZSfmTkpo


http://www.youtube.com/watch?v=xUt5OS-agUM

http://www.vimeo.com/4511014

some fur and smoke
http://www.vimeo.com/5432910

Homer melting:)
http://www.vimeo.com/4414156

some houdini rigid body basics for beginners.
http://www.youtube.com/watch?v=3yImVRM2Bqg&feature=related

thereīs more cool houdini tutes from this guy on how to create forests with L-systems similar to those videos on sidefx homepage, but Im already out of topic for this thread.


Michael

Mr Rid
07-21-2009, 09:30 PM
Nothing beats Extreme Loading for structural physics-
http://www.youtube.com/watch?v=hDBsSht1_VA&feature=channel_page

Blastcode-
http://www.blastcode.com/gallery/sample.php?pid=105

Rayfire & Physex-
http://www.youtube.com/watch?v=8qslD29O_1A
http://www.youtube.com/watch?v=lmBQ60Acsbg&feature=related
http://www.mirvadim.com/index.php?id=videos