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conehead
06-11-2004, 02:24 AM
Hello,
i have now L8 for about two months and tested the dynamics but i've seen that L8 has many problems with calculating. most problems with the rigid bodys. the collision settings none-box-sphere aren't helpful for collisions. what i really miss is the accuracy of the calculating like impact3.

Carm3D
06-11-2004, 03:35 AM
Does Impact3 still work for you with 8?

conehead
06-11-2004, 04:48 AM
i had a demo of impact 3 and tested it in L7.5. the rigid bodies in lightwave 8 should be as good as impact 3.

Kvaalen
06-11-2004, 05:07 AM
Originally posted by conehead
the collision settings none-box-sphere aren't helpful for collisions.

I haven't experiencent very many problems with inacurate calculations... maybe it has to do with your setting?

But I wanted to say, that I find the box, sphere, plane and obviously objects collisoin very helpful. :)

Robi
06-11-2004, 05:23 AM
Originally posted by Carm3D
Does Impact3 still work for you with 8? Yes, Impact3 works with LW8, and its a lot better than LWs Hardbody Dynamics.

Carm3D
06-11-2004, 05:37 AM
Are there any soft-body (well more specifically, cloth) alternatives to what Lightwave 8 offers? I find LW8's cloth sims with collision to be interminably slow. Thanks.

-EsHrA-
06-11-2004, 06:12 AM
same with hard-fx when using it on a rather complex object....ud need a second renderfarm to calculate those fx....

awfull slow... :(



mlon

theo
06-11-2004, 08:13 AM
I'll be shocked if someone doesn't post and write "Well, if you want more advanced effects power then you need to pay extra for that power and get a dedicated plugin".

Some joker always seems to feel better saying that in discussions about dynamics.

Robi
06-11-2004, 11:25 AM
Originally posted by Carm3D
Are there any soft-body (well more specifically, cloth) alternatives to what Lightwave 8 offers? I find LW8's cloth sims with collision to be interminably slow. Thanks. Not that I know of.

hrgiger
06-11-2004, 01:07 PM
I've had some problems with LW 8's dynamics. Not speed of calculation though, you really should use a lo poly stand in object and then use meta link to attach the motion to your high poly one. It's a snap. So, I would argue that the dynamics are not slow, just more to the point, you don't know how to use them yet.

My problem is with the collisions. I've yet to have a good setup where the cloth didn't pass through the body in quite a few spots. I've tried and tried but no matter what I do, I can't get accurate collisions. I've tried different resolutions of my mesh, triangulation, collision offsets, etc..... Nada works. I sure hope someone posts now and tells me, I just don't know how to use collisons because, I'd really like to hear that I'm doing something wrong.

Carm3D
06-11-2004, 01:48 PM
Theo,

> I'll be shocked if someone doesn't post and write
> "Well, if you want more advanced effects power then you
> need to pay extra for that power and get a dedicated
> plugin".

> Some joker always seems to feel better saying that in
> discussions about dynamics.

That's what I was hoping for. But I guess there are no cloth alternatives available for LW.

hrgiger
06-11-2004, 02:12 PM
What I'm hoping for really is that LW 8's dynamics is just laying a foundation for a much greater dynamics system. I'm hoping that Newtek doesn't feel that they got the new dynamics in 8 so there would be no need to improve them.

theo
06-11-2004, 03:49 PM
Hey Carm- don't take me wrong friend. I wasn't referring to the guy who is looking for this specifically.

Kvaalen
06-11-2004, 05:12 PM
Originally posted by hrgiger
My problem is with the collisions. I've yet to have a good setup where the cloth didn't pass through the body in quite a few spots. I've tried and tried but no matter what I do, I can't get accurate collisions. I've tried different resolutions of my mesh, triangulation, collision offsets, etc..... Nada works. I sure hope someone posts now and tells me, I just don't know how to use collisons because, I'd really like to hear that I'm doing something wrong.

Is the collision object selected before you hit calculate?

Carm3D
06-11-2004, 06:18 PM
> Is the collision object selected before you hit calculate?

Why would that make a difference?

hrgiger
06-11-2004, 07:48 PM
Yes, I'm curious, would that make a differnece?

EDIT: I just went ahead and tried it. It doesn't seem to make a difference.

Kvaalen
06-12-2004, 01:06 AM
For some reason if I have cloth or soft body dynamics applied and it's suppposed to collide with an object, for some weird reason it doesn't work unless the collision object is selected. I suppose I'm doing something wrong. BTW, I never read the docs about the dynamics... I just played with them. Maybe I should. :)

pooby
06-12-2004, 03:33 AM
But I guess there are no cloth alternatives available for LW.

That's until Syflex gets ported to Lightwave. (There are plans.)

Mind you, it's very expensive.

PHilly[Dee]
06-12-2004, 12:29 PM
Just a thot--in LW7.x, on the FX_browser panel there was an options button. That would call up a dialogue box, and there was a "resolution" setting. I know when I lowered the resolution to 5cm or less, I'd get more accurate calculations (but take a hit on calc time). Is there anything like it in 8?

Kvaalen
06-12-2004, 04:54 PM
Originally posted by PHilly[Dee]
Just a thot--in LW7.x, on the FX_browser panel there was an options button. That would call up a dialogue box, and there was a "resolution" setting. I know when I lowered the resolution to 5cm or less, I'd get more accurate calculations (but take a hit on calc time). Is there anything like it in 8?

Ahhh!... the 7.0/7.5 interface... :)

The FX browser still exists in 8, though I haven't tried to see if it helps with the new dynamics.

Dodgy
06-12-2004, 05:25 PM
In each dynamics plugin panel there's a resolution setting in the ETC tab.

Also I find it helps if your cloth object has a very even quad mesh. That is to say all the polys which make it up are roughly the same size and together very regular. Then you Parent your high poly mesh to it and use Meta link like HRG said.

The hard dynamics Box self collision type actually does proper mesh collision (I've used it with triangular objects and it's worked correctly) I think it's mis-named rather than doing just cheesy box collision.

If your cloth obejct interpenetrates, that's what the EditFX is for. I know it's not perfect like the sames from Sysflex seem to be, but it helps. I'm always a bit suspicious of sample avis anyway but I think they've delivered the goods? Anyone seen it in action?

HowardM
06-13-2004, 08:15 AM
Originally posted by Dodgy
The hard dynamics Box self collision type actually does proper mesh collision (I've used it with triangular objects and it's worked correctly) I think it's mis-named rather than doing just cheesy box collision.

Are you sure about that? Or are your pieces working correct with a collision floor, and not Self?
I cant seem to get realistic SELF collision detection from irregularly shaped objs, or broken objs...
I think Box and Sphere are just that...
:(

Dodgy
06-13-2004, 11:31 AM
Darn, you're right HM, I was deluding myself. Must have been just concidence that it seemed to work the time I checked :P

Bum, they should fix this for the next release :P

HowardM
06-13-2004, 11:56 AM
Sorry! ;p
Yeah, lets hope to god Ino reads and listens, and Newtek pays him!

Emmanuel
06-14-2004, 12:15 PM
http://www.dstorm.co.jp/FXBREAK/e/FXBREAKDocs/collision.html

I dunno if these are the same that ship with LW but there seems to be sphere, box and node...?

Are these tuts included with 8 ?http://www.dstorm.co.jp/FXBREAK/e/FXBREAKDocs/tut.htm

Dodgy
06-14-2004, 02:59 PM
That's very helpful. I can't find any of these docs on the discs.

You don't happen to know where the FXmotion docs are?

Karmacop
06-14-2004, 08:55 PM
Collision by node only works for collisions with other objects, what's being asked for is collision by node for self interacton and interaction.

Emmanuel
06-15-2004, 05:31 AM
Sorry, my mistake.

Karmacop
06-15-2004, 08:35 AM
Something that I've found makes a difference .. though doesn't fix it, is by adding hard body dynamics as well as a collision to an object. It doesn't fix everything but I find it makes the calculation more realistic ... i think anyway ...

Ztreem
06-16-2004, 02:31 PM
Here's a little test with HardFX in LW8 I put together, a couple of rings falls into a cup with node based collision. It's not perfect but works OK, I think.

HardFX Test (http://www.mistanimations.com/FXTest_Rings4.avi)

The movie file is in Xvid codec. about 500Kb.

Enjoy! :D

conehead
06-17-2004, 01:28 AM
thats one of the things i meaned. the rings arent moving right. when you look exactly you will see the rings never stop moving and move wheres is no "force". (i am austrian if you dont understand me)

Ztreem
06-18-2004, 01:56 PM
I think they move quite realistic if you don't count the last falling ring. But it's just a quick test... I will try to do a better one soon.