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mccabejc
10-04-2008, 09:25 AM
I haven't used the cloth feature in LW for a very long time, and it looks like it hasn't improved much since it was introduced many years ago. Y'know, back when it was a plugin from Japan that Newtek bought and kludged into LW.

I tried a simple, 2-D, tripled, flat planar object, set as thick cloth with self collision, and added a flat, horizontal planar collision object for it to collide with. Did an "IKB Calculate", and it crashed.

I've been monkeying with cloth on and off for a couple days, and it seems to crash a lot. When you re-select a different type of cloth preset it seems to not like it, and in general it seems pretty unstable. Not to mention how horrendously user-unfriendly it is...

Anyway, is it just me ?

OlaHaldor
10-04-2008, 09:52 AM
I've never done cloth before, but I'd like to get into it. However, I get - like you - constant crash to desktop whenever I hit the Calculate button. I'm on LW 64-bit.

mccabejc
10-04-2008, 03:14 PM
Oh, and the Abort rarely seems to work. And often the calculations go off into never-never land and you can't stop it unless you kill the Layout process.

Same as it used to do many years ago.

Y'know, this is just crazy. I'm certainly not a LW newbie, as I've been using it on and off since the Amiga days. But how the heck can Newtek expect to get anywhere with this if it can't make a simple cloth simulation a little more bulletproof for the average user?

Maybe I'm doing something goofy, since I haven't been at this lately, and as we all know the cloth interface is ridiculously non user-intuitive. But if they can't clean this up a bit after all these years they might as well give up.

mccabejc
10-04-2008, 04:48 PM
Okay, this is priceless...

I was trying to get a simple rectangular cloth object (like a towel) to fall and collide with a basket. Tried it first in LW, and the solution either crashed, or when it worked I tried numerous times to get the cloth settings so everything solved nice. And it never worked. I could never get the cloth to hang on the basket, it always fell thru and flew off to never never land.

So on a hunch I fired up Poser, loaded the exact same objects, and did an identical simulation, and VOILA !! Worked first time, every time. Solid, no crashes, and the solutions were MUCH faster than what I was getting in LW.

How embarassing for you anti-Poser guys...

Ztreem
10-05-2008, 05:14 AM
Cloth doesn't crash very often for me. You have to remember that poser got cloth simulation more recent then LW so it should be alot better, you can also use blender for cloth if you can't handle LW cloth.
If you post your objects I can do a quick test and maybe solve it for you.

Korvar
10-05-2008, 05:32 AM
Okay, this is priceless...

I was trying to get a simple rectangular cloth object (like a towel) to fall and collide with a basket. Tried it first in LW, and the solution either crashed, or when it worked I tried numerous times to get the cloth settings so everything solved nice. And it never worked. I could never get the cloth to hang on the basket, it always fell thru and flew off to never never land.

So on a hunch I fired up Poser, loaded the exact same objects, and did an identical simulation, and VOILA !! Worked first time, every time. Solid, no crashes, and the solutions were MUCH faster than what I was getting in LW.

How embarassing for you anti-Poser guys...

I've always had a problem with Poser's cloth sim - if I do anything even vaguely complex, it fails. Doesn't crash, or give me an error, or anything useful, it just stops. Really annoying.

But then, when I try and do the same sim in Lightwave, it usually just does a couple of frames and then grinds away endlessly with no obvious result.

Not a lot to choose from :)

mccabejc
10-05-2008, 09:36 AM
You have to remember that poser got cloth simulation more recent then LW so it should be alot better

I'm not sure I understand the logic on that...

Korvar
10-05-2008, 10:03 AM
I'm not sure I understand the logic on that...

I think it's something like: Newtek is making incremental changes to an old, primitive cloth sim system, while Poser started with a more modern and advanced cloth sim system. Not sure how much sense that makes :) Could be entirely reasonable, but my brain's not working well just now.

Oedo 808
10-05-2008, 10:13 AM
Hurray! Bonus points for Korvar. :thumbsup:

Ztreem
10-05-2008, 10:26 AM
I'm not sure I understand the logic on that...

Do you follow the logic that a new car built in 2008 is much better in all areas compared to a car build in 1920?
The dynamics system is newer in poser compared to LW, this doesn't have to mean anything but in this case it seems like it does. Blender is free and have cloth dynamics as well, surely better than Lw's clothFX. ClothFX in LW is not very good but works most of the time if you know what you're doing.

In your case with a towel colliding with a basket then cloth FX should work just fine.

mccabejc
10-05-2008, 11:05 AM
Do you follow the logic that a new car built in 2008 is much better in all areas compared to a car build in 1920?

Yeah, I suppose, but that's a whole 'nother argument of marketing over substance. I just don't think it's appropriate logic to use with LW.

My guess is that Newtek bought the cloth plugin from (geesh, I can't remember the name of the group from Japan who was writing dynamics plugins for LW years ago...) and the folks working on LW now don't have intimate knowledge of the zillion lines of code comprising the cloth/softbody stuff. And I think this has been the case ever since they bought it, since it is still a pretty poor excuse for cloth dynamics, and its user interface, which was pretty horrendous at inception, hasn't changed much.

I would think that over the years the LW folks would have finally figured out the code and made substantive changes/improvements, as opposed to brand new code which can take years to de-bug, especially something so complex as cloth.



In your case with a towel colliding with a basket then cloth FX should work just fine.

Uh...but it doesn't...

Ztreem
10-05-2008, 11:15 AM
Uh...but it doesn't...

It may be a user error or some other odd error, can you show some pics of what kind of effect you're after? maybe I can help you to make it in LW. ClothFX works most of the time for me, you just have to think in a simplistic way when working with it.

archijam
10-05-2008, 12:54 PM
What are we mumbling about? Post the objects orrready! :)

mccabejc
10-05-2008, 12:55 PM
...maybe I can help you to make it in LW.

Thanks for the offer Ztreem. But it's a lot easier for me to just do it in Poser. It seems like there are some built-in default parameter settings in Poser that somehow work first time without a lot of tweaking. My experience with LW is that you end up spending lots of time tweaking settings that you don't really understand.

Carm3D
10-05-2008, 01:36 PM
I bought SyFlex so I don't have to deal with ClothFX anymore.. Wooot! But anyway.. Here are some tips for you:

1. Use Collision primitives instead of polygon collisions if you can. Hugely faster, but friction doesn't behave as well to my experience.

2. Load your cloth object into Modeler. Turn off sub-divisions and save. Then turn on sub-divisions and save as an alternate object. Do your cloth calcs with the non-sub-D version and you will get MUCH BETTER RESULTS. Then save the calculation's .MDD file. Replace the object with the sub-D version.

3. Make sure your collision object is tripled (no quad-polys), and avoid sharp corners. Round out those sharp edges and your life will become easier.

4. Don't use the Calculate button on the ClothFX interface. Open the FX_Browser panel and use that one. Much easier to abort calculations with that.

5. Purchase SyFlex.

Ztreem
10-05-2008, 01:55 PM
Thanks for the offer Ztreem. But it's a lot easier for me to just do it in Poser. It seems like there are some built-in default parameter settings in Poser that somehow work first time without a lot of tweaking. My experience with LW is that you end up spending lots of time tweaking settings that you don't really understand.

OK, that's fine. Use the tool that works best for the job.

mccabejc
10-05-2008, 02:40 PM
Thanks for the tips, Carm. It's kinda funny that LW wants tripled polys, and Poser wants quads.

Poser didn't seem to have any problems whatsoever with collisions with a fairly complex object, so I think I'll stick with it. And it's FAST !!!!

Ztreem
10-05-2008, 03:03 PM
I never use tripled polys with cloth and it works just fine, subpatched objects also works just fine. Would be fun just to see what you're doing, if you don't mind showing I would love to see a pic.