Hi,

Now that 9.5 has shipped and some love was given to Cloth, anyone have any success? The new shelf tools are nice for Constraints (pinning cloth to a moving RBD guy worked great and easily) but I'm struggling to simply get the cloth to hit the RBD guy.

Can't post my file unfortunately, if people have had success I'll keep plugging away

Cheers,

Peter B

Hi Peter

I think your cloth IS colliding but the solver steps are to few to calculate a correct collision

in the cloth solver start with a minimum substeps of 5
also modify the volume offset of the cloth in the collisions tab

this settings will depend a lot in you cloth speed and scale etc.

Hey Varomix,

Yes, I cranked up the steps in the Cloth solver, and got some colliding but it still looks like ass. I'll see if I can tear down the file and post it up. It's just a guy in a simple shirt bowing.

Thanks for the help!

Cheers,

Peter B

See this thread for some cloth collision tips. You've probably tried ‘em already, but just in case you hadn’t:
http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=13068 [sidefx.com]

Hey,

OK, I admit defeat. In the attached I have a deforming torso bending forward. I just want the shirt to act like a shirt.

I've tried the RBD object as volume and not, a wide variety of settings on the Cloth Solver node (which is incompletely documented, btw) subdividing the shirt more etc.

All I get are insanely slow sims that look like … er, not a shirt.

If the Cloth stuff isn't up to a shirt, that's cool, I think it'd be good to just let people know it can't be done. If it can be done, then I'd like to see it

Cheers,

Peter B

Peter, your file doesn't seem to open correctly in 9.5 master (osx & linux). I suspect it's because of the gzip compression. Would you mind posting it without? Would love to take a look.

cheers,
Abdelkareem

Hey,

Try "gzip -d' on the file

Cheers,

Peter B

Hi

oh man!!

yeah I played with the file for a while and I couldn't get any good results, and the sim is so damn slow, I actually tried last night at home for about 2 hours and nothing, the body interpenetrates the body etc, I thought that it will be easier at work in the morning, fresh, in my powerful workstation, but no, same story, tweak stuff for about an hour and nothing, I was getting very frustrated so I thought that I'll give it a try in maya.

In ten minutes I had a useful result, need tweaking, think it took me more time to export the models, add some bones and set some keyframes than the actual cloth setup, made the shirt triangles, made a cloth object, made the skin a cloth collision object, selected the SHIRT PRESET for the cloth, hit play, looks nice, modified the collision offset a little, and done.

I don't wanna sound bad here, I just wanna see both sides of this, I love houdini, I'm doing lots of thing in it now, but I thing cloth still needs some work, or maybe there's a setting we didn't tweak to make it super fast.

I won't let this go, I'm gonna keep testing till I get a nice result, maybe later today @ my break.

Yeah, I've tried too. PolyCapped the ends of the body, Trail SOP to compute its velocity. And the result it slowness and crazycloth. What else can we do? A shirt is Cloth 101.

I've found that if you increase substeps, things get worse. The collision gets more violent.

Hey guys,

thanks for trying! I'm going to give up for now, it's just too slow to even test with unfortunately. Maybe 9.6 will have some additional cloth love

Cheers,

Peter B

I looked at the files that you provided.

I found that there is a problem with the interaction between cloth and deformable volumes: Cloth points receive far too great an impulse as a result of the collisions with the deforming volume. The slowness of the simulation is a direct consequence of this.

I logged this issue as bug 31990.

Thank you very much for providing files and taking the time to look into this.

Michiel

Hey Michiel,

Cool, glad it's an identified bug. If you can fix it in 9.5 I'd be happy to keep experimenting!

As Jason pointed out, this is pretty much Cloth 101 Do you guys have a similar scene file (i.e. character moving around with a shirt and/or pants) tuned for quality/performance that you can share even in undocumented form?

Cheers,

Peter B

Hi Peter,

A fix for this should go into 9.5. I don't have any files with dressed characters that I'm allowed to share. However, as soon as the problem is fixed, I can optimize the settings for the shirt example that you posted in this thread and post it again.

Michiel

Hi Michiel,

Cool, sounds good! I own all that content so feel free to post it up here for all to learn from. If you want I can send more of the character with pants too, which you can throw up on the Exchange once you have it working if you want to share some examples.

Cheers,

peter B

I also have some characters that I could share, anything I can help with, just let me know.

and once again, Side Effects shows everyone else what a good company does, they listen the users, nice.

thanks

Looks like there have been quite a few bug fixes to cloth over the last month. Has anyone tried this again since to see if it works now?

(and sure, I could try it myself, but I haven't really used it much before, so not sure I've got much to compare new results to :twisted: )

-z

I'm getting some things working better. We had a specific scenario where pulling a cloth over a tube looked fine, but the reverse had popping and hopping. If something causes cloth to bounce off a collision object, then it falls back on the object which is still pushing towards it, there seems to be bad mojo happening with the calculation of the resultant force, which causes the cloth to get a very strong force that doesn't seem to be controllable with all the usual suspects like friction, shear, etc. I've noticed the Cloth Object now has bubbled up ‘Contact Damping’ and ‘Friction’, which I can only get to help a bit by setting them both to zero. :shock: Even then, the above scenario still bubbles. To be fair, we have *not* got a response that it's fixed yet, so I'm withholding judgment. I would like to get some sense of how these values work, since for me they tend not to act as I might think.

I can get it much much closer, though. The reason we're obsessing with this scenario is that its the single most common use, as clothing you want animated objects pushing cloth more than the other way around. At least by beating up various parameters I can get specific scenarios where this works. Alas, there are some that still don't.

The popping buzzing when dropping cloth over things is much better, I've got some nice stuff from it. I'm not sure you can completely come to rest in a lot of cases, but this is pretty common. Just have to blend out the animation when you're done. A cloth version of RBD autofreeze would be cool.

Cheers,

J.C.

In order to attract the man of your dreams, it helps to dress in a way
that honors your beautiful body.

Hey, context-sensitive spam! Nice!