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RobertoOrtiz
04-26-2005, 10:10 PM
Ok in order to clear the air, I have taken the liberty of posting a series of threads
where ideas on how to improve Lightwave can be posted in an organized fashion.
The idea is to provide an one stop place where developers (from Newtek, or independent)can come in and get ideas.

The titles and links for the threads are below

HOW TO IMPROVE LIGHTWAVE: LWO Format (http://www.cgtalk.com/showthread.php?t=233923)
HOW TO IMPROVE LIGHTWAVE: Rigging (http://www.cgtalk.com/showthread.php?t=224487)
HOW TO IMPROVE LIGHTWAVE: Web 3d (http://www.cgtalk.com/showthread.php?t=195126)
HOW TO IMPROVE LIGHTWAVE: CAD (http://www.cgtalk.com/showthread.php?t=228499)
HOW TO IMPROVE LIGHTWAVE: Character Animation (http://www.cgtalk.com/showthread.php?t=175156)
HOW TO IMPROVE LIGHTWAVE: Dynamics (http://www.cgtalk.com/showthread.php?t=175161)
HOW TO IMPROVE LIGHTWAVE: Effects (http://www.cgtalk.com/showthread.php?t=175224)
HOW TO IMPROVE LIGHTWAVE: Layout (http://www.cgtalk.com/showthread.php?t=175167)
HOW TO IMPROVE LIGHTWAVE: Modeling (http://www.cgtalk.com/showthread.php?t=175149)
HOW TO IMPROVE LIGHTWAVE: Rendering (http://www.cgtalk.com/showthread.php?t=175166)
HOW TO IMPROVE LIGHTWAVE: SDK and plug-in development (http://www.cgtalk.com/showthread.php?t=175698)
HOW TO IMPROVE LIGHTWAVE: Interoperability with other apps (http://www.cgtalk.com/showthread.php?t=175697)
HOW TO IMPROVE LIGHTWAVE: Workflow (http://www.cgtalk.com/showthread.php?t=176496)
HOW TO IMPROVE LIGHTWAVE: Expressions (http://www.cgtalk.com/showthread.php?t=178670)
HOW TO IMPROVE LIGHTWAVE: 2D (Stealing Ideas from 2D Programs) (http://www.cgtalk.com/showthread.php?t=181807)
HOW TO IMPROVE LIGHTWAVE: Operating Systems (http://www.cgtalk.com/showthread.php?t=181864)
HOW TO IMPROVE LIGHTWAVE: NonLinear Editing (http://www.cgtalk.com/showthread.php?t=191251)
HOW TO IMPROVE LIGHTWAVE:Latest CG Papers (Tell us about Bleeding Edge CG Research ) (http://www.cgtalk.com/showthread.php?t=182306)

Looking forward to your ideas.
-R

twidup
04-26-2005, 10:22 PM
well, first, lets clarify this
Cloth and soft bodies are two totally different things.
Too many ppl group them together when they are totally different

Cloth systems are good for things like, well cloth, hair, fur.
Soft bodies are good for skin(somewhat if setup right) jello, jiggly stuff basically.

LW cloth needs to be faster adn easier to use, but allow enough control to influence different areas of the cloth, and even to dial off the effects, POST SIM. this would further be helped by teh ability to paint weight maps that define the area to dial off in LAYOUT.

have never used softbodies in LW, so no comment.

Celshader
04-26-2005, 10:56 PM
LW cloth needs to be faster adn easier to use, but allow enough control to influence different areas of the cloth, and even to dial off the effects, POST SIM. this would further be helped by teh ability to paint weight maps that define the area to dial off in LAYOUT.

I think ClothFX can already do that now, by weightmapping the MotionSize in Local-type playback. I'll have to check to see if that's the exact right setting, though...

Me, I still think ClothFX needs better docs.

rich novak
04-27-2005, 03:10 AM
I just asked for help with ClothFX the other day.

My biggest gripe with LW, now that I'm really getting into it, is the Cloth FX, or lack thereof. It seems like there are hundreds of different properties to it, and I simply don't have the time to learn how to tweak the system just right in order to accomplish believeable cloth.

I'm a one-man studio and I have a full-time job, so I don't have much time as it is. I rely on Lightwave and Poser for my 3D work, because each seems to be the best at what they are for. Lightwave is a superb modeler and renderer. Poser is great for 3D people and animating them. To bring Poser content into Lightwave (including animated 3D people) there's Greenbriar Studios. However, one big limitation is the plugin from GS will not import Dynamic Cloth from Poser.

That's unfortunate, because Poser 5's Cloth Room is fantastic. It lacks presets, but it first allows you to use a certain number of frames to drape the cloth over whatever object you want to cover, and then lets you calculate the cloth based on the animation with relatively few settings. You control how the cloth behaves and there you have it. Done.

I love Lightwave. But when it comes to 3D cloth simulation, the P5 cloth room destroys Lightwave's Cloth FX.

If the designers could come up with a similar cloth simulator for Lightwave, that would be the greatest.

twidup
04-27-2005, 03:14 AM
it might have it. like I said, I dont use it that much. I have told Chuck this before. feature and performance of MD2k, ClothFX, and pretty much the dynamics line dont hold a candle to Syflex, or any of the systems out for other packages or any of the proprietary ones I have used.

I think the bigger point for me is, some of the control is there, others arent or are a bitch to get working properly.

and Yeah, better docs would go a long way to helping.

yeah Roberto, you should start a thread on the LW documentation specifically
I think that would get more replies than anything

HowardM
04-27-2005, 11:29 AM
Please excuse me for being slightly rude, but I think its time this was said. (although I most likely have no idea what Im talking about :p )

I think the solution to our ClothFX problem is to have a larger team working on it, besides Daisuke Ino and whoever else is working with him (if there is anyone else?!)

The lack of any real documentation alone makes me think that only Ino (even though I was told otherwise by Jim Plant a year ago) is creating the Dynamics and this is why there is no proper documentation.

I believe with some proper documentation, and some proper control settings ( ie. not X number of different settings that basically screw each other up when you tweak one or two things that worked fine prior to tweaking the next setting, - you all know what Im talking about right?) , that ClothFX could really work well....the biggest problem to learning how to use it, is its all hit or miss with no real feedback, which is a total waste of time to most people....so how can any of us really use its power correctly? Teach us with proper Docs and simple controls that dont blow each other out when tweaked....PLEASE! :D

Also things like realistic self collision in ClothFX but none in HardFX makes me wonder, how can these be written by the same person?! There just seems to be too many things thrown together with no real forethought of how to make all the Dynamics work well together...

Now, all in all, im not saying Ino isnt a genius for creating FX, and I know It may seem like Im just whining here, but I think we deserve better....something written and designed by a team of people ... Dynamics that all work well together with a realistic interface ...

Thanks!

adrencg
04-27-2005, 02:12 PM
Now, all in all, im not saying Ino isnt a genius for creating FX, and I know It may seem like Im just whining here, but I think we deserve better....something written and designed by a team of people ... Dynamics that all work well together with a realistic interface ...

Thanks!

Also, settings that have a limit, or at least we know what the optimal limits of usability are. How do I know to use a spring setting of 1, or some ridiculous number like 20000? Does friction work better in the 1 to 3 range, or 1 to 1000? Who the hell knows? Make everything 1 to 100%...this problem was an inheritance from the silly value ranges from Motion Designer. Start over.

Lots of presets would be great also.

Also, when some ClothFX polys just simply go right through the collision object, you just want to to quit. If I have to tweak every setting for an hour just fix it, then its obvious LW is still absent of a half decent Dynamics engine and still in garage-hack land.

I am definitely using it, but for nothing more complicated than some simple hair splines.

Mike

Celshader
04-27-2005, 03:49 PM
ClothFX isn't that bad. Give it better docs, multithreading, and more graceful collision detection in cramped quarters, and I'll be happier.

Now, a few words for folks still new to it...

---
---

ClothFX is not a limited, cloth-specific plug-in. Its original name, "FX_MotionDrive", made it clearer that it was a general-purpose dynamics engine. The original Motion Designer Docs showed not only cloth examples, but also hair, particles, jiggling breasts and falling petals. All of the settings make sense...once you know what they do.

That's the catch -- it takes practice to learn what the settings do. The current docs don't tell you much. It took me about three months' worth of experimentation to figure out what the settings did in the old Motion Designer.

The visual examples of the settings in the old MD docs helped:
http://www.spaudio.com/LW_stuff/Indexe.htm

It also took me a while to adjust to the new ClothFX way of doing things.

If you don't have three months, then put some time in searching for ClothFX tutorials and information. Searching for ClothFX information on this forum will turn up several posts explaining some of the more mysterious settings.

Rich Novak, please read both of my posts here about Spring vs. Stretch Limit:
http://www.cgtalk.com/showthread.php?t=222805&page=2&pp=15

...and my post on how to use FX_MetaLink_Morph here:
http://www.cgtalk.com/showthread.php?t=221096

...and my post on NodeMatch here:
http://www.cgtalk.com/showthread.php?t=165416&page=2

I think I wrote more, but I don't remember now. My schedule keeps me from writing more thorough answers than what I've posted here and what I wrote in your earlier thread (http://www.cgtalk.com/showthread.php?t=233821&highlight=ClothFX).

It takes about as long to master ClothFX as it does to master the art of surfacing. Feel free to pull apart the free scene files (http://www.celshader.com/gallery/md/) I have on my website and use their settings in your work.

bobakabob
04-27-2005, 04:48 PM
Some thought provoking points made in this thread. I agree with Howard's post especially. IMO ClothFX has potential, but needs better documentation and more tutorials with suggested settings - it still seems too much of a 'black art' at the moment.

I appreciate Celshader's point about practice. Many thanks for the links and files - they look awesome :) But presets would also be a lifesaver... it's not conducive to good health to be left experimenting with bizarre value settings ('Pick a number?') on a tight deadline.

Looking forward to future updates. Newtek usually do a great job on LW's interface - hypervoxels is a good example of sound, intuitive design which encourages experimentation, whereas ClothFX is just plain scary.

Cheers

Bob

PS Would anyone be generous enough to share good ClothFX settings for polygonal hair?

Gollum
04-27-2005, 05:01 PM
I agree with most that has been said so far. The dynamics were a cool addition, but the novelty has worn off and the limitations are just too significant!

First of all the documentation is too sparse. Basic info about what each value is supposed to do is provided, but translating that into predictable results is almost impossible. This tendency of wildly crazy results and vertices flying all over the place, that occurs as soon as a non-primitive collision object and/or complex motions are involved, needs to be adressed. As it is, clothFX is good for the classic "piece of cloth interacts with ball and box" stuff, but runs into serious trouble when trying to do anything more complex. Almost seems like a demo version of some sort.

Another thing that bothers me is that, unlike the rest of LW, it isn't intuitive to use. How often do we Wavers brag that our software is easy to pick up and just use, without fighting the technicalities first. The intuitive nature of LW's UI has always been a major strength. The dynamics are the complete opposite however! There is no abstraction going on, they feel like a direct interface to the calculation, as if designed for internal use by the original programmer only.

Just a few things I'd like to see improved:



stability, there are many little issues that can cause it to crash or provide crazy results
workflow when working with multiple dynamics/collision objects
calculation speed and accuracy, specifically when interacting with non-primitive collision objects
more user friendly and intuitive interface
controls need to have meaningfull descriptions and sensible, consistent input ranges
better resting, relax and stop options
presets that actually work

HowardM
04-27-2005, 05:20 PM
PS Would anyone be generous enough to share good ClothFX settings for polygonal hair?

Thats an issue with most simulation packages though, you really cant have presets because of the way it works - on # of points and/or polygons...so one setting that works for a 10x10 grid will not work the same for a 1000 poly shirt object. I dont know the solution, or if there is one because of the nature of the sims....

adrencg
04-27-2005, 06:00 PM
PS Would anyone be generous enough to share good ClothFX settings for polygonal hair?

Weight .3
Spring 100
Viscosity 1
Resistance 1
Substructure 1000
Stretch Limit 10
Polygon size (make it whatever you need under 100 to get it's length correct)

Mike

Gollum
04-27-2005, 06:01 PM
ClothFX isn't that bad. Give it better docs, multithreading, and more graceful collision detection in cramped quarters, and I'll be happier.
True, it isn't that bad. Like you pointed out, it can be used for many things besides just cloth, sometimes better than for actual cloth. That's why I keep saying its a promising implementation, but its ease of use and quality could certainly be further improved.

Maybe its a naming issue, clothFX kinda sounds like its supposed to help you with creating dynamic clothing, yet that's one of the things that are very hard to get working properly. Dynamic clothing is getting pretty important these days though. I'm not expecting a point and click solution, but something a bit more managable (as in not requiring dozens of hours of tweaking settings every time), even if that means it'd be more geared towards clothing in particular...

rich novak
04-28-2005, 01:52 AM
Great thoughts everyone.

Stability is my major issue at the moment. Too many things just cause it to freeze. I'll let it sit for an hour or two and come back and it's still on the same frame.

Celshader
04-28-2005, 04:42 AM
Stability is my major issue at the moment. Too many things just cause it to freeze. I'll let it sit for an hour or two and come back and it's still on the same frame.

Hitting the CTRL key will stop the calculation. 8.0 was crueler about updating the display on a two-monitor system. Switching to another app during a calculation and returning would cause the display to stop updating. If the calculation got "stuck", you wouldn't know. In my experience, 8.2's been far more responsive. 'Course, it could've been because my last batch of calculations went by so quick that I never switched to another app during the calculation. Hm.

For what it's worth, more ClothFX tips that come to mind:

Whenever the calculation gets "stuck," it means ClothFX is having a tough time coming up with a point-placement solution that makes all of the set parameters happy. If everything goes fine and then gets "stuck," cancel the calculation with the CTRL key and try relaxing some of the settings. From what I remember, a high Viscosity of 20 can be great for hair, but on clothing meshes a high setting like that can really stress ClothFX and cause it to get "stuck" on the first frame. If that happens, I'll rachet it down to 1 and gradually increase the Viscosity between test-calculations by 1 until it looks fine.

Stretch Limits of 1% are also hard on ClothFX in clothing simulations. For free-moving hair or flags it might not matter much, but clothing meshes are more complicated than flags and hair. If a calculation gets "stuck," try relaxing the Stretch Limit to 10% or higher, and reduce the Polygon Size to help eliminate sagging material.

Weight values of 0.0 are a no-no in ClothFX. Motion Designer accepted Weight values of 0 without complaint, but ClothFX gets grumpy about zero-values in the Weight setting. Lower it to 0.1 for incredibly light material, or turn off Gravity altogether if you don't want the material to react to Gravity. But don't set Weight to 0.0.

Other settings that might cause ClothFX to get "stuck" -- Compress Stress higher than 1000%, Spring and SubStructure forces higher than 5000. By themselves, each of these high settings might not cause any harm and can look fine for a given situation. However, if you have everything cranked up to the nines, you're not giving ClothFX much breathing room at all. Sometimes you can crank up all the settings -- Compress Stress higher than 1000%, Spring/Substructure set to 30000, Stretch Limit at 1%, Viscosity at 20 -- and ClothFX will somehow find a way through that specific mesh/collision situation. It's better to not crank all of the settings up that high at the same time, though -- you'll probably have slower calculations if you force ClothFX to think really hard about the calculation.

If the material covers a great distance in a short period of time, ClothFX and Motion Designer both can go crazy trying to solve the effects of a great force like that acting on the points. Increasing Resistance to 10 can help calm down the points for that one specific shot that calls for a T-shirt to fly across a room within a scant few frames. Resistance affects the points' willingness to move at all, so a Resistance of 10 makes them reluctant to move and counteracts the effects of a great motion-force.

$0.02

huskerdude
04-28-2005, 12:40 PM
If the subject is how to improve ClothFX, there's one obvious first step:

I would love to see Newtek commission Celshader to rewrite the ClothFX/Motion Designer user guide using the original MD and MotionDrive documentation as a starting point and then provide illustratative scenes of all the features available. Time permitting :-). Many features are not covered in the existing user manual. Celshader's posts over the past few months/years have uncovered the possibilities of nodematch, reference nulls with MD, local mode and other 'buried' features in ClothFX/MD that need promoting. I had no idea that you could apply ClothFX to a proxy object covering a small portion of your cloth and then apply that back onto the 'main' object. I even put in a feature request for a local mode working in its own coordinate space irrespective of where the MDD was calculated when the feature was already in there. IMHO, Motion Designer/ClothFX is a valuable asset for Newtek and needs to be clearly explicated and demonstrated by someone who knows what they're doing.

Once there's a thorough written document which describes what MD/ClothFX can actually do then I guess these are some features that would improve the tool:

A) MDD Layering. The ability to layer MDD's on top of one another and 'mix' them using weight maps and envelopes.

B) MDD Sculpting. A tool like Mark Wilson's Point Oven that could soft edit MDDs in Modeler (EditFX on steroids) and integrate the edits back into the MDD, smoothing the sculpts over time. This would be a great way of smoothing away collision errors, sculpting in creases and general deforming the resultant MDD in any way you saw fit.

On the housekeeping side it would be cool if ClothFX supported key move so that morphs could be applied on top of the effect and multithreading would be great.

On the ease of use issues, it's hard to know how much simpler the tools could get without sacrificing flexibility. It's interesting that Syflex for Maya (I haven't seen the implementation in XSi) is very similar to MD/ClothFX in terms of the types of parameters available and the range of values you can input. According to our TD all 'Elastic Body Models' work in the same way using the same basic calculations and parameters but I guess much could be done to provide a range of preset options and to consolidate some of the seemingly similar functions - maybe a layered interface offering simple and expert options, for example.

One tip that Celshader didn't mention was to comp the cloth in separately. That way you can let some collisions and intersections happen without worrying too much i.e. if a T-shirt passes into a character's chest at some point and your camera is facing the character head on then you don't actually need to 'fix' the collision because if you render the cloth out separately and then layer it back on top, the 'collision' won't register...

Celshader
04-28-2005, 03:56 PM
I would love to see Newtek commission Celshader to rewrite the ClothFX/Motion Designer user guide using the original MD and MotionDrive documentation as a starting point and then provide illustratative scenes of all the features available. Time permitting :-).

:blush:

I should confess that NewTek did ask me at SIGGRAPH in 2003 if I could write dynamics documentation, because of the Motion Designer tests in my dynamics gallery (http://www.celshader.com/gallery/md/). Shortly thereafter I got sucked into working on The Last Samurai, then the LightWave jobs just kept coming after that non-stop.

For what it's worth, I wrote everything I knew in early 2004 about dynamics for that LightWave 8: 1001 Tips & Tricks (http://www.wordware.com/tnt/) book. I've gotten to know LightWave [8] dynamics a lot better since then. If I ever get a breather, I should probably gather up all the dynamics posts I've made on these forums and cobble them together on a web page or something.

monovich
04-28-2005, 04:02 PM
I would be very interested in that.

:)

rich novak
05-01-2005, 06:12 AM
Me too.

Anyhow, I was on worley.com and I believe it's their Polk product which has a plugin called Whirly Points? This is described as a dynamics plugin which works easily for cloth. Has anyone tried it yet, and if so, what do you think?

Thanks!

pooby
05-01-2005, 11:26 AM
What ClothFX could do with, (a relatively quick fix) is the option of a Post processing scan which takes the already solved data and applies a 'smooth curve' option to eliminate jiggle by analysing each points average translations and that of the surrounding points.
It seems to me that there is a lot of unwanted vibration that could be dealt with post-process rather than going back to square 1 and re-writing the whole core.

But the biggest issue is getting more accurate collisions. perhaps some way of it 'knowing' when it's screwed up and gone into a frenzy, so it shuttles back a few frames to try a better solve.

Celshader
05-01-2005, 04:49 PM
What ClothFX could do with, (a relatively quick fix) is the option of a Post processing scan which takes the already solved data and applies a 'smooth curve' option to eliminate jiggle by analysing each points average translations and that of the surrounding points.

Yeah, smoothing multiple points would be neat. I think right now the "Smooth" function in EditFX only lets you do the above function on a point-by-point basis. Activate both Fix settings, set the EditStart and EditEnd to frames close to the offensive set of frames, find a frame in-between the EditStart and EditEnd frames, select the point in question and choose Smooth from the "command" drop-down list. It'll smooth out the jittering point's motion path.

If you do not activate both Fix settings, Smooth will make every frame on the point's motion path just like the current frame. If you activate only one Fix setting, the Smooth effect will ramp in/out at the Fix point and make all other frames just like the current frame. Good for keeping those one or two points that just won't settle down after hitting a stationary collision object.

angelking7
06-24-2005, 09:13 PM
Hi everyone

I had big problems with MD and it was a real pain when it was about collision, good cloth reaction, subtle moves, stability and especially rendering time.

I was about to leave MD forever and run on another app then i found out that if you resize your scene by 10 or 20, calculations are faster (almost realtime if u run a 3000polys cloth), collision works far better, the cloth reacts very better and it's way more stable.

I was always working at a 1:1 factor size. Now i'm at a 10:1 and things work very well.

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