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cyclopse
10-07-2015, 05:41 PM
Ok, so I was up 'till 5am last night trying to get some workable cloth. I'm used to Maya cloth, and it's.... well, different. I got something almost workable in this test (sorry for the BASIC character animation here... it was just a test of the cloth really). Problem is that in the beginning it seems to anticipate the jump (moves before the jump) and then at the end, it seems like collision detection on the blouse disappears and it just goes completely wonky.

https://www.youtube.com/watch?v=Seo3ZwR3zt8

Here's what the geometry looks like (Collision object is in the background layer):
-The shirt:
130205

-The skirt:
130206

Both objects also use subdivs (imposed "last") - Shirt level: 2, Skirt level: 1

Here are the cloth settings:
-The shirt:
130207130208130209130210

-The skirt:
130212130213130214130216

Any help is appreciated. I'm lost in the settings and getting conflicting info on EXACTLY what each setting does. LW documentation reads different than Light Wiki which reads different from online tutorials, etc, etc, etc. Hope I gave you guys enough info...

What really baffles me is that during the fast / extreme movement the shirt works great (other than the crawling collar)... when she stops though... that's when it decides to go crazy? WTF....

Snosrap
10-07-2015, 06:52 PM
I think you might find more success using Deforming Bodies in Bullet than you will with ClothFX. ClothFX is older tech.

ranhell
10-07-2015, 09:18 PM
Why is your cloth in tris as in not pollys? cloth or bullet work just fine you just have to know what they don't like and what they like in your model setup.

cyclopse
10-07-2015, 10:11 PM
I think you might find more success using Deforming Bodies in Bullet than you will with ClothFX. ClothFX is older tech.

I'm trying bullet... but I can't get it to recognize the female as a collision object. I tried the bake MDD "solution" people suggest, but the results are... unpredictable. You're right, the cloth works better when she holds still, and I use her as a static object, but once I switch her to deforming object... all hell breaks loose.

cyclopse
10-07-2015, 10:13 PM
Why is your cloth in tris as in not pollys? cloth or bullet work just fine you just have to know what they don't like and what they like in your model setup.

Are you saying that neither works with tris vs. quads? I used quads, switched to tris per a suggestion, and most of the cloth motion smoothed out a bit. I'm really hoping I can solve this. Maya just works better for this stuff, but I would have hoped after all these years LW would have gotten better and gotten rid of all the kludge.

erikals
10-08-2015, 03:14 AM
what you see often occur with ClothFX,
one of the big reasons why NT added Bullet Soft Bodies.

there is also $200 Syflex, as an option.

but complex movements with ClothFX is often a no-go, as the cloth jitters when a vertex hits another vertex.

btw, you are correct, tris are recommended for cloth.

cyclopse
10-08-2015, 03:20 AM
Thanks everyone... got it figured out. Just need to polish it to get rid of the quivers...


https://www.youtube.com/watch?v=UqYoTzG8zJw

Turns out it was a combo of the spring not being high enough, and the collision object's collision distance.

Nothing is named properly on the parameters. You'd think spring is elasticity, but really it's how strong things are drawn together... which is really what viscosity is in fluid dynamics... so viscosity is what? I dunno. Like I said... it's like I need to get out chicken bones and sacrifice a lamb to pray to the animation gods for things to work.

erikals
10-08-2015, 03:26 AM
yes, again, ClothFX is a real challenge when it comes to complex cloth collision animation.

i highly recommend Syflex or Bullet for complex stuff.

Surrealist.
10-08-2015, 04:18 AM
Thanks everyone... got it figured out. Just need to polish it to get rid of the quivers...


https://www.youtube.com/watch?v=UqYoTzG8zJw

Turns out it was a combo of the spring not being high enough, and the collision object's collision distance.

Nothing is named properly on the parameters. You'd think spring is elasticity, but really it's how strong things are drawn together... which is really what viscosity is in fluid dynamics... so viscosity is what? I dunno. Like I said... it's like I need to get out chicken bones and sacrifice a lamb to pray to the animation gods for things to work.

you could do a lot better than this with cloth FX. And I do not recommend tris. Sorry to conflict. I see the theory in that but in practice it will look better with denser quads and subpatch to last.

Some links:

http://forums.newtek.com/showthread.php?104570-Help-Surrealist-Feel-like-ending-it-all

http://forums.newtek.com/showthread.php?126654-Is-Cloth-simulation-in-LW-still-bad

The quck rundown:


Start with a fresh Cloth Plugin.

Scrap the one you have with any settings. You want to start over.

I am going to give you the quick rundown. Some of this you may already know.

Now make sure you have your cape with a fixed set of points around the collar.

Make sure also you have a map applied to the same points with 100 percent value to be used by the upper spine bone. It can be the same map if you want.

Set the cape object bone properties to "Use Bones From" The body object and make sure the fixed points now follow the movement of that bone. Don't calculate anything yet. Just make sure those points move with the bone.

Now the offset between the cloth object and the collision object is an addition of the units set on the collision properties tab of the cloth object and the radius value of the collision object properties. These two values make a force field around the two objects. This is real world units in whatever you have set as your units. Meters by default. So it is scale dependent.

When the cloth mesh penetrates with force field it confuses the solver. This is true in any cloth solver actually and is one of the main things to understand. Playing with these two distances until your cloth object does not go crazy is the first step.

So make sure you lift the cloth object high enough so that it does not penetrate this feild.

For example if the cloth and collision are set to 10mm that is a total of 20mm. So set your cloth object so it is about 30mm away from the collison object. Let it fall on the force field.

Now keep all other settings at their default values.

Set the gravity for the cloth object. -9.8 depending on scene scale of course.

Add some friction and fix power. Start with 100 on each for the Collision Object.

For the cloth object set the spring and sub structure to 1,000 and go up form there as needed. I commonly use 3,000.

Start a calculation.

Things should be relatively smooth. But yo'ull have some jitters.

Go to the Etc tab of the cloth object and set the resolution to something low like 1mm.

This is the only thing that will quiet the cloth. Set it as low as 100um if you have to.

That should be good enough to render. Not perfect but good enough.

For the best results. Use the cloth object as a cage to drive another object that has thickness if desired. Especially around the collar or hims. Parent the thick object to the cloth object and use metalink to drive it.

Don't try and simulate a thick object.

My Test:

https://vimeo.com/138828641

First animation with the dress and blouse.

Farhad_azer
10-08-2015, 02:59 PM
Do you activate self-collision in bullete? it slows things down but brings really good results.

bobakabob
10-08-2015, 03:56 PM
This is pretty old tech and not sure it's really worth the hassle for extreme CA moves like this when a combination of morphs, weight maps and bones will give you far more control. Bullet is up to date, so worth checking out for clothing.

ranhell
10-08-2015, 05:06 PM
cyclopse you did a better job at it on the last video. for lightwave cloth is better in quads vs tri's the more detail or better flow for cloth you add more pollys. this especially true with bullet. keep up the good work. surrealist nice cloth simulations.

Surrealist.
10-08-2015, 05:15 PM
Thanks and Robert is correct, for fast moving stuff, classic cloth has no (working) self collision. It is older tech. I have not played with Bullet yet, so can't offer any tips for that.

Greenlaw
10-08-2015, 06:47 PM
Also, if you're going to use Bullet, calculations are way faster with proxy objects parented to the bones (i.e., pills, spheres, lower res versions of body parts, etc.), and you should see very little difference in the quality of sim itself. Just be sure the proxy shapes are completely airtight.

I would even go as far to say you can get better results this way and you'll spend less time messing around and waiting on results. This is the reason why using proxy objects for collision is fairly common for this type of animation in production.

G.

ranhell
10-08-2015, 09:26 PM
The old cloth dynamics can do things bullet can’t do in lightwave yet. For me bullet has been challenging because it’s a different work flow from the old cloth dynamics system. I'm not talking about the GUI I'm talking about the proxy setup it’s completely different.

old cloth dynamics sample just a few minutes ago

https://www.youtube.com/watch?v=5StzwkHruas&feature=youtu.be

and a bullet sample.

https://www.youtube.com/watch?v=xs-VueKV3j8

Surrealist.
10-09-2015, 12:13 AM
Also, if you're going to use Bullet, calculations are way faster with proxy objects parented to the bones (i.e., pills, spheres, lower res versions of body parts, etc.), and you should see very little difference in the quality of sim itself. Just be sure the proxy shapes are completely airtight.

I would even go as far to say you can get better results this way and you'll spend less time messing around and waiting on results. This is the reason why using proxy objects for collision is fairly common for this type of animation in production.

G.

Absolutely true. I find this to be true with any cloth solution I use. The Collision object is never the same as the actual rendered object and his highly optimized for the purpose of collision only.

Surrealist.
10-09-2015, 12:19 AM
The old cloth dynamics can do things bullet can’t do in lightwave yet. For me bullet has been challenging because it’s a different work flow from the old cloth dynamics system. I'm not talking about the GUI I'm talking about the proxy setup it’s completely different.

old cloth dynamics sample just a few minutes ago

https://www.youtube.com/watch?v=5StzwkHruas&feature=youtu.be

and a bullet sample.

https://www.youtube.com/watch?v=xs-VueKV3j8

There are two things I have noticed about Bullet. The first is that everyone seems to complain about the set up and how it is difficult. And second don't find the sims to be that pleasing to me. The cloth always seems rubbery.

I like the way classic cloth looks from my tests. It is just lacking features like working self collision.

But since I have not used Bullet yet, I refrain from making any definite conclusions.

erikals
10-09-2015, 01:30 AM
[Bullet] The cloth always seems rubbery

Absolutely, no question. http://erikalstad.com/backup/misc.php_files/smile.gif

djwaterman
10-09-2015, 01:56 AM
It certainly does and I've seen no examples where it doesn't. Blender on the other hand...( but let's not go there).

Surrealist.
10-09-2015, 03:18 AM
lol yeah.

Well, Has anyone played with it to try and mitigate the rubber factor?

ranhell
10-09-2015, 08:18 PM
lol yeah.

Well, Has anyone played with it to try and mitigate the rubber factor?

No for now I'm just trying to get a solid understanding of what bullet does not like to help me get better cloth sims then I will work on refining the smoothness. like many others I'm sure how found many things that bullet does not like. here is my short list so far your proxy mesh works better when converted to tris. it also does not like overlapping geometry body's very temperamental with the collision distance property. have to reset bullet when applying different changes you can spend hours tweaking your model to find that was never the issue so pay close attention to that one. start your cloth with as few pollys as possible this helps speed up the testing time with bullet less time wasted. cloth has to have its own layer with bones because of the influence of other weight maps bullet issue only. the old cloth dynamics does not have this issue. for a more stable cloth dynamics I use LW 9 weight maps don't affect cloth dynamics sims. that's the simple stuff I have yet to have any luck with multi layer cloth sims with out bullet freaking right out. this is as far as I have gotten with bullet and cloth. bullet works great for blowing **** up that came out working great right out of the box!

VermilionCat
10-10-2015, 04:32 AM
I highly suggest to use bones instead of simulations.

erikals
10-10-2015, 05:28 AM
well,... only for low-res cloth

...otherwise bones won't kick it

Greenlaw
10-10-2015, 12:53 PM
Here's a quick and dirty Bullet clothing test. I don't actually need this kind of cloth effect for 'B2' but since I had Sister's old mocap test handy, I threw a skirt on her to see what happens.

I should qualify this by saying I don't normally use LightWave Bullet for clothing like this, so this is a learning experience for me too. We're going to need it for the characters in our next short film after 'B2' so I figure I may as well get a handle on how this works now. :)


https://vimeo.com/142006826

I think the results are not bad for a couple hours of work this morning. If this test was for actual production, I would probably increase the friction on the legs--it's a bit 'slippy' on the legs right now, like the cloth was made from silk. Anyway, this test was super easy to set up in Bullet but I found there are a few things to watch out for.

The basic setup is as described earlier: a sphere was used as the collision object in the hips/belly region and four capsules for the leg segments. I didn't time this sim but it was in the ball park of 10 minutes for about a 1000 frames. IMO, this is much faster and easier than it would be with ClothFX.

More explanations to come...

Greenlaw
10-10-2015, 01:07 PM
The main thing I learned was that when using Deforming for cloth, Bullet only sees the original un-subdivided mesh for the sim, so you'll need to be sure your mesh supports the deformation level you want. You can still use Subpatching on top of that but just be sure to have enough geometry underneath it for the desired effect. Here's an illustration


https://vimeo.com/142009369

I was trying to figure out what contributed to the the 'rubbery' quality some users mentioned earlier. I think this happens with many simulations tools, not just Bullet. For me, it has to do with weight and stretchiness, and also where the stretchiness is occuring.

To elminate 'stretchiness', you want to leave volume scaling at 100%. Setting it higher or lower will cause the fabric to stretch.

You need to use the Mesh Filter to pin your fabric but be aware this this is a rigid fixing of points. Part of what makes cloth look 'rubbery' is that there is too much motion near the pinned region. You can reduce this slipping effect by added a gradual falloff in Shape Retention. In this case, I applied a linear weight map from top to bottom and used a Gradient layer to control where and how much flexibilty should occur along the length of the skirt. (I recommend setting up a simple test like the one above for study because it's fully interactive. This will give you a clear idea of how the features work and figure out what you will need to do for your character.)

The one glaring 'error' in the Sister test above is the skirt sinking into the arch of her back. This happens because the skirt is simply parented to her hip bone and it is not deforming with her body. I guess if I was really concerned about this, I would use the rig to properly deform that region of the skirt. I'll worry about that when I actually need this effect. Also, there is no collision on her hands, which is why her fingers penetrate the fabric--didn't care, this was just a test to see if Bullet was 'good enough' for character clothing. Based on this quick test, I think so...others may certainly disagree.

Hope this info helps. I feel like I forgot to mention something. If I remember what that was, I'll be sure to post more info. For now, I got some house chores to catch up on. :p

G

Greenlaw
10-10-2015, 01:35 PM
Oh, I just remembered a few things.

Some details really should be modeled into the fabric, like folds in the joints or where fabric hangs, like at the shoulder or hips. You can use Joint Morphing to drive when this fold appears. If you want to do this, I recommend using SoftFX to sculpt your targets and save the results as Endomorphs. You can use Joint Morph + to apply the effect. (I didn't bother with the previous two examples--these are just quick tests, not meant for actual production work.)

Add a tiny bit of Dampening to the fabric. This will make it appear lighter and should also reduce the 'rubber' effect. 2% should be plenty but experiment.

One thing users might struggle with is object penetration. In the Sister example, the collision proxies worked reasonably well but every now and then, a bit of the actual (non-collision) leg or belly would poke through. Rather than fuss over the collision settings, I found it a lot easier to simply hide the underlying mesh with transparency. If I need to see Sister's legs at some point, I can always put an envelope on the transparency. (You can actually see where the legs have been hidden when she passes the camera. Fixing this is simply a matter of showing a little more leg of course.)

As you might have guessed, I hate struggling with software and I'm always looking for shortcuts. My feeling is that if something seems really difficult to do, I'm probably trying to do it the hard way. This doesn't mean you need to sacrifice quality to get things done faster, it just means you should look for smarter and more efficient ways to get the same or better results. IMO, animation and vfx work can be hard enough when things are going well so I try to avoid things that make my job more difficult than it needs to be. Plus, I like to get home by dinner time.

Will post additional tips and tricks if I think of any more.

G.

Surrealist.
10-10-2015, 04:29 PM
Great to have these tests done. Real helpful to have this information. I think we have found a lot of things that are common with cloth fx sims and Bullet. In fact most of the things I found out about LightWave cloth FX I have found to be true in Blender, XSI (Syflex on ICE) and Maya nCloth. With Maya coming out ahead as far as various options. But the basic cloth sets ups are the same.


Thanks for sharing this info. We can refer to this thread now for Bullet Cloth.

Snosrap
10-10-2015, 07:46 PM
Thanks Greenlaw! Looks great.

ranhell
10-10-2015, 08:23 PM
thanks for sharing your experience with bullet cloth dynamics Greenlaw. Its always nice to see someone else showing good progress in their journey of just trying to get it to work right. I have gotten the same results as Greenlaw for better cloth by adding more pollys to the mesh.

https://www.youtube.com/watch?v=f9Aq22mZZWg

Greenlaw
10-11-2015, 01:40 AM
Glad to hear the info is helpful. :)

A few more thoughts: think about is how your geometry needs to be constructed. Just getting the shape may not be good enough. While the construction of a flat piece of cloth may be pretty obvious, a realisitic shirt can be much more complicated if you want it to fold and wrinkle like the real thing. Consider the polygon flow carefully--just like with a character model, you want your mesh to deform just like the object it's representing. A carelessly modeled piece of clothing is probably going to bend and fold in an unnatural manner. Also, keep in mind that a higher density of polygons can wrinkle and fold with more detail than areas with lower density of polygons. In general, you probably want to keep the density fairly consistent but you may want to intentionally mix it up where it makes sense. For example, cuffs and collars are typically stiffer than the rest of the clothing, so you might use fewer polygons in those areas. Minimizing the polygon count where it makes sense may help you keep your calc times lower.

One of the reasons Marvelous Designer's clothing deforms so nicely is because the program requires you model clothing as if you were stitching real fabric cut from actual clothing patterns. I don't think it's necessary to go that for LightWave Bullet simulations but it's probably good to keep in mind during modeling or retopologizing.

G.

Surrealist.
10-11-2015, 07:02 AM
Great tips. The one caveat to modeling though is going from high to low poly areas can produce artifacts, or well, basically just strange looking results. From my experience anyway.

One practice that works well for me us to have a set up where I have a simulation cloth object and a more detailed (thickness, seams, pockets, buttons) cloth render Object and drive one with a cage (or in Maya) wrap deformer. This works reasonably well with Metalink in LW. Although there are some cases you may run into issues for example under arm pits.

Mentioned earlier was using cloth sim to deform a starting position of a cloth object. I find this real useful especially to create objects that maybe are a little more difficult to model into a realistic starting position.

Here is an example of a blouse top. (the parts what were to actually be seen under the vest).

In advance my apology for the Maya screen caps. Just happens to be this is the best example I have of it to hand. It works just as well in LightWave.

Here it is in its original modeled position.:

http://blenderartists.org/forum/attachment.php?attachmentid=311455&d=1401205228

The by weighing parts of it and letting it drop it looks like this:

http://blenderartists.org/forum/attachment.php?attachmentid=311456&d=1401205317

Collar perfectly formed and initial wrinkles set.

You could actually just deform an object like this from here with no cloth sim. For some parts, this is good enough.

Here is the high definition version. Modeled from the original cage object, and simulated into position. It has thickness and a seam.

http://blenderartists.org/forum/attachment.php?attachmentid=311458&d=1401205788&thumb=1

And a real good example of an object you would want to model flat. Then animate and simulate into an initiate state and freeze. A shall is just a flat triangle or square folded. UV map it first then freeze into position. The problem being solved here is that you getting the object into a good natural position from which to simulate. And modeling it this way would be more difficult. Sculpting is another option. But I don't know. This just looks more natural because it mimics what is actually happening in the real world.

http://blenderartists.org/forum/attachment.php?attachmentid=311463&d=1401208049

Driven by bones and animated much in the same way it would be positioned in the real world.

http://blenderartists.org/forum/attachment.php?attachmentid=311464&d=1401208068

And finally the sim settles into position around the collision object and frozen from here to be the starting position.

http://blenderartists.org/forum/attachment.php?attachmentid=311465&d=1401208086

Here it is in action. Note the dress was done with the technique I described with a even density cloth sim object driving the high detail object with thickness, seams etc.

130293

130294

Again apology for the Maya screen grabs. But rest assured these techniques work reasonably well in LightWave. Granted there are a few issues in LW classic cloth. And I have no real idea how to set this up with Bullet, but maybe Greenlaw will give us a sample... ? :)

Greenlaw
10-11-2015, 11:52 AM
That's pretty cool! And thanks for posting those tips.

TBH, I really don't have a lot of experience with form fitting character clothing using LightWave Bullet--in fact, the example I made yesterday morning is my first with a fully rigged character--but based on what I've learned so far, I think the info you posted should carry over to Bullet. I'll keep it in mind when modeling the clothing for our next short film project.

To me, the test result was very encouraging...and we're really going to need this on our next film. We have Syflex here too but I haven't really used it yet. LightWave Bullet, on the other hand, has gotten me through more than a dozen different video game and film productions in the past three or four years, so I have a certain comfort level about using it.

G.

Surrealist.
10-11-2015, 02:14 PM
Great. Looking forward to your tests when you get that far. Maybe I'll get a chance to have time with 2015 before too long and give bullet a go as well. These tips you gave will come in handy to dial it in. :)

ranhell
10-11-2015, 06:41 PM
WOW, Surrealist those are some good example of work arounds for modeling cloth with sims. I'll have to give that a try some time. I hope all this info is helping Cyclopse.

Surrealist.
10-11-2015, 06:52 PM
Cool. If it was not clear, these are all techniques I started developing years ago with Cloth FX. I simply carried these ideas and expanded on them through Blender Cloth, then Syflex on ICE and finally Maya nCloth. nCloth is probably the best solution right now all around I think.

But the point being that these are all things I learned here on these forums and also developed on my own initially. There was a guy Drik here some years ago and we were kind of both sharing ideas for a while. And also of course Dodgy. Greenlaw was not to my memory involved as much at the time, But it is good to see someone continuing to carry the torch so to speak.

I remember at the time really cloth fx was voodoo. But thanks to the help of a lot of guys here we cracked it. And I think now it is safe to say there is no real mystery as to how to make it work. And it looks like Greenlaw has made some strides with Bullet and soon that won't be such a mystery anymore either. :)

jwiede
10-11-2015, 07:05 PM
At this point, seems like anyone serious about cloth sims should (probably IS) using Syflex anyway. It offers better (often faster) simulation than either ClothFx or Bullet, and setup feels much "cleaner" than either of them (in not requiring nearly as many workarounds/compromises). Syflex for Lightwave is also a great bargain -- I'm surprised it isn't getting more of a mention in this thread.

erikals
10-12-2015, 02:08 AM
Syflex is nice, more of a "Bullet / ClothFX" mix.
it has a rubber look also, but much less than Bullet.

https://www.youtube.com/watch?v=U_QLP08PNQo
https://www.youtube.com/watch?v=g-C_hpfOhyk
https://www.youtube.com/watch?v=1InNMuDD6ak

just haven't had the time to test / use it all that much.

Surrealist.
10-12-2015, 08:06 AM
At this point, seems like anyone serious about cloth sims should (probably IS) using Syflex anyway. It offers better (often faster) simulation than either ClothFx or Bullet, and setup feels much "cleaner" than either of them (in not requiring nearly as many workarounds/compromises). Syflex for Lightwave is also a great bargain -- I'm surprised it isn't getting more of a mention in this thread.

To be fair, it is simply and only because I think we are talking about native LightWave tools. No other reason. It is a valid discussion, sure. But it is not being excluded here out of ignorance. You want to discuss Syflex. Maybe there is another thread for that? Just saying. This thread is about LightWave native cloth solutions. It is kind of off topic to suggest using another solution. Even if better. That goes for rendering modeling etc as well. Every thread on every topic does not have to derail into the best plugin. Not everyone can afford to use them.

Just keep it on topic. That's all.

That said, I don't want to be thread cop. Nothing wrong with discussing it. But keep in mind for some people the native solution is all that is available. So I prefer to keep it on that topic. Just me.

cyclopse
10-12-2015, 11:34 AM
Here's a quick and dirty Bullet clothing test. I don't actually need this kind of cloth effect for 'B2' but since I had Sister's old mocap test handy, I threw a skirt on her to see what happens.

I should qualify this by saying I don't normally use LightWave Bullet for clothing like this, so this is a learning experience for me too. We're going to need it for the characters in our next short film after 'B2' so I figure I may as well get a handle on how this works now. :)


https://vimeo.com/142006826

I think the results are not bad for a couple hours of work this morning. If this test was for actual production, I would probably increase the friction on the legs--it's a bit 'slippy' on the legs right now, like the cloth was made from silk. Anyway, this test was super easy to set up in Bullet but I found there are a few things to watch out for.

The basic setup is as described earlier: a sphere was used as the collision object in the hips/belly region and four capsules for the leg segments. I didn't time this sim but it was in the ball park of 10 minutes for about a 1000 frames. IMO, this is much faster and easier than it would be with ClothFX.

More explanations to come...

Sorry I've been away for a few days. I agree... bullet works MUCH better overall. However, I'm looking for cloth to hug the object, not use primitives. I want silk that falls on the geometry nicely. You can't use bones with it. Can't use an MDD with it... it's fairly useless for my purposes. If I were doing what you're doing here... sure. If you can help me use my original geometry (and not cutting it up into chunks because that will create gaps when joints flex that a super sheer cloth will get trapped in)... I'm all for giving it a shot.

cyclopse
10-12-2015, 11:37 AM
To be fair, it is simply and only because I think we are talking about native LightWave tools. No other reason. It is a valid discussion, sure. But it is not being excluded here out of ignorance. You want to discuss Syflex. Maybe there is another thread for that? Just saying. This thread is about LightWave native cloth solutions. It is kind of off topic to suggest using another solution. Even if better. That goes for rendering modeling etc as well. Every thread on every topic does not have to derail into the best plugin. Not everyone can afford to use them.

Just keep it on topic. That's all.

That said, I don't want to be thread cop. Nothing wrong with discussing it. But keep in mind for some people the native solution is all that is available. So I prefer to keep it on that topic. Just me.

Amen. I didn't switch away from Maya (that works just fine without any plugins) to have to buy plugins for every single thing I want to do. That's actually why I originally left Lightwave in 2004.

Plugins should be there to do what you could originally do easier, or to just bring about a different thing all together. Not to bypass a feature (or in this case 2 features) that don't seem to work at all. At least that's how Newtek SHOULD look at it.

Greenlaw
10-12-2015, 12:49 PM
...(and not cutting it up into chunks because that will create gaps when joints flex that a super sheer cloth will get trapped in)...

Not necessarily. Giving the collision objects less friction and a little bit of collision margin should cover that. A setup like this is not uncommon in the industry with any 3D software because it's reasonably accurate and it's so much faster to work with.

But it sounds like you've pretty much made up your mind that you absolutely need a deforming single mesh collision object for your project. That certainly works with Bullet too. It's just very slow to calculate with a high level of polygons. For an accurate sim with high-res geometry and mdd, you should expect your calculations to take hours rather than seconds or a few minutes, like mine do. Also, remember that you need real geometry for collision, not subpatches. If you're using Sub-D's in Layout, the collision may be inaccurate because, as mentioned earlier, Bullet only sees the original un-subdivided mesh for collision. But in many cases, the collision mesh will not need to be as high-res as your final render mesh though, so you can save some calc time there.

Good luck.

G.

Additional note: I don't know what's normal behavior for Bullet in general as I've only used the LightWave version, but it's probably not a bug that LightWave Bullet does not account for sub-division surfaces in its calculations. In any case, if it's technically possible, there probably should be an option to account for sub-division surfaces. IMO, this is certainly worth a report and a feature request to LW3DG for 2016.

Surrealist.
10-12-2015, 01:03 PM
If you do need the solid hugging geometry, which is what I do most the time, yeah it is heavy on calc times. The calc times back in 9.6 on my old machine for that cloth stuff I did were a couple of hours for each piece. And it was split up into two layers. One for the top and one for the dress, with the top using the dress as a collision object after the dress was cached. I think I found out that this is fairly usual in production for high quality cloth sims like that.

The calc times on that Maya cloth were also very long. Also split up into layers. Dress first and shall after.

cyclopse
10-12-2015, 01:08 PM
If you do need the solid hugging geometry, which is what I do most the time, yeah it is heavy on calc times. The calc times back in 9.6 on my old machine for that cloth stuff I did were a couple of hours for each piece. And it was split up into two layers. One for the top and one for the dress, with the top using the dress as a collision object after the dress was cached. I think I found out that this is fairly usual in production for high quality cloth sims like that.

The calc times on that Maya cloth were also very long. Also split up into layers. Dress first and shall after.

Yeah... I'm buckled up to sit on my butt a lot and watch progress meters. The problem is that I can't seem to get it to work at all. I move the mesh of the top (only trying it with the top first) to be on the model. I use the model as fixed... the cloth sits on it perfectly. I use it as deformer, the cloth falls right through. I de-apply the bones, and it doesn't move, and cloth goes funky (like turns into a christmas tree star). Try the MDD thing, and it falls right through.

Greenlaw
10-12-2015, 01:14 PM
One more suggestion, which I think was already mentioned by somebody else but it's worth repeating: you can improve collision quality be turning up the Dynamics Framerate. This still assumes you have the polygon count to support the collision and deformations you want to begin with. There is no specific value you should use but just try 240 or 360 for starters. Setting the framerate higher will slow down your calc time but you can dial the value up or down from there to optimize it.

Greenlaw
10-12-2015, 01:19 PM
Regarding MDD for collision, is your collision object water-tight? If not, I believe that could cause inaccurate results. Otherwise, you need to use the Surface or Vertices mode, but that may give you different results from Solid mode. Not necessarily better or worse, just different.

You also need to set the Subdivision Order to After Displacement, even when you're not using Subdivision Surfaces. You probably know that already but just tossing in some more suggestions.

G.

wyattharris
10-12-2015, 01:48 PM
Regarding the rubbery look in Bullet, the movements that generated this result were pretty basic but I thought the output was pretty good. Only had 1 1/2 months to complete this challenge and I kept refining the process as I went so some elements look a bit more dynamic than others. I don't think I have a video of it in motion just the turnaround.

https://www.youtube.com/watch?v=n1cMc0wn3S4


Sorry I've been away for a few days. I agree... bullet works MUCH better overall. However, I'm looking for cloth to hug the object, not use primitives. I want silk that falls on the geometry nicely.
It doesn't have to actually be a primitive. A low poly cage will work. Not sure if that's what you meant but just wanted to clear that up. Below is the type of proxy objects I used to animate Toph's clothes. The left is the bracelet object. The bracelet and leather cuff were dynamic hard body bullet objects and the cloth funnel is soft body bullet.
http://www.wyattharris.com/cgtalk/hmc/37-ff/bracelet.jpg

Surrealist.
10-12-2015, 05:16 PM
Yeah... I'm buckled up to sit on my butt a lot and watch progress meters. The problem is that I can't seem to get it to work at all. I move the mesh of the top (only trying it with the top first) to be on the model. I use the model as fixed... the cloth sits on it perfectly. I use it as deformer, the cloth falls right through. I de-apply the bones, and it doesn't move, and cloth goes funky (like turns into a christmas tree star). Try the MDD thing, and it falls right through.

Rendering and simulating. lol the bane of our existence.

Sorry I can not offer tips on Bullet though.

Luc_Feri
10-13-2015, 04:26 AM
Some great tips there Surrealist.

That is something I have used before, the option to save out the Trans Object from Layout is very handy indeed. :D

Surrealist.
10-13-2015, 04:50 AM
Yeah indeed.

@wyattharris, thanks for the screen caps and explanations. Nice model!