View Full Version : cloth squeeze

01-12-2004, 10:57 AM
Go here http://xm2.com/xm6/ and watch the intro.

How can I achieve the "squeezing effect" of the cloth.

I have been working with an example from a book (Essential LW 3d - Timothy Albee) that shows a cloth drop onto a sphere.. looks awesome, The example I am working with uses motion design (SCENES>>MD_Controller).

I have set up my scene where cloth drops onto some text, BUT, I cannot get the cloth to "squeeze" around the text like on the website above. Everything I have made looks pretty desent, but the cloth "drapes" over the object, rather than "squeezes around it" it. Do I make the cloth heavier? (which I have tried, but to no good) and how can I get it to move close to the base of the text (where the txt rests on the ground)


01-12-2004, 12:31 PM
The cloth on the intro has a very high poly count...what about yours?

could we get a look at a wireframe of the scene your doing please?

And I will try to be of more help

01-12-2004, 01:02 PM
I have 729 polys in my cloth, it is seems to be fine for now, but the final render I'll definetly crank the count up (recreate the simple object - load and apply a saved md file)

I almost have it, I went home for lunch to get the big 'ol LW manual, it explains things a bit better, I think I know where my settings are off, but now, I have a few other issues I am trying to work out.

Feel free to add in more input, as I continue to work this out.

01-12-2004, 01:54 PM
OK I upped the poly count of my cloth to 10201 (tripled)

I have a ground plane, my text, which sits motionless on this ground plane, and my cloth, that falls downward. My camera is positiond directly above the scene, so you get the effect of the "all of a sudden it takes shape" (you actually do not see the cloth fall, as it is a solid color, but you see it "take shape" as it falls over the text.

My problem now is, the text is visible when the cloth covers it. The manual states (page 18.11.. bottom of page - skin thinkness) that if I have this problem I should increase the skin thinkness of the collision object, which in this case would be my text. I cannot go above 0.6-ish without it (LW) taking forever to caculate, and a thinkness of 1.0 is simply out of the question.

I can do the basic "cloth falling on a ball, then sliding off" tutorial and understand it well, but this technique eludes me.

I have made every effort to try to mimic the cloth draping over the text, I am buried in the manual (LW chapter 18.. currently on page 18.13) but I am at a loss now. I have made many adjustments to just about everything, as I understand them.

Is there another technique that I can try to achieve this effect?

01-12-2004, 10:04 PM
Question. Do you need to see the text? If not, don't render the object.

What you can do is to increase the calculate resolution (tab option in the MD controller). A good value is between 200 and 1000.

01-13-2004, 07:59 AM
OK, I am offically frustrated. I can't get this effect to work, the cloth falls through my text. I can however use a box, a sphere or any other basic shape just fine. I have done massive research on this and can't find anything anywhere... except a bazillion tutorials on the cloth and ball technique. I have 6 different lightwave books open on my desk right now... nothing.

I have re-created my text object thinking that the polys were not true, therefore the collsion dection would not effect those "see through polys" - nothing.

I have played with this thing for 2 days now and I just cannot achieve the effect. Someone, somewhere, reading this board has to know what the issue is. Why can I not drape a cloth over text, without the text popping through? Any other object I use works fine. Is MD limited to basic, non-complex objects or something? I just don't get it.

Could someone please attempt to create a quick example? just drape a cloth over some text (cloth falls onto text) I would like to compare your MD settings with the many that I have created over the past 2 days.


01-13-2004, 04:44 PM

The key to this is lots of geometry on both objects. I am trying to sort out a file for you but will be a couple of days as the calculation times on my machine are astronomical.

The surface settings should only need to be basic....fixed on the box and thin cotton for the cloth...other than that set the gravity to -9.8. It would also help to subpatch the cloth but thats gonna push the calculation up even higher.

Have a look at this curtain tutorial and look at the way he sets the cloth geometry. http://www.imadjinn-cgi.com/TUT/curtain_tute/curtain_tute.html its the minimum yor gonna need for what your after.

will post the file as soon as i can.

01-13-2004, 05:05 PM
Ya, I have seen that one already. I have pretty much given up on the effect, because I came to the conclusion that, to cover a complext object like text, would require a serious amount of calculation time. By serious, I mean like 20+ hours per frame.

I have studied the ball & cloth and the curtain very well. The deformation of the cloth around a complex object like text, is simply way to much for a computer to handle at this point in time. To ripple the cloth as in the curtain, I can do, to fire a ball at hanging blanket.. simple... wave a flag, even easier.... I have figured out all these while trying to get the cloth to work around the text. I can pretty much do the effect on a simple shape.. box, diamond, sphere...etc, but not a text object.... too many corners and different sides. As soon as I use a text shape... my cloth falls through the text (text shows through.)

At this point I am looking into some 3d party plug-in to help me in my quest. I have seen a few really nice ones that do liquid effects, I am sure I could re-surface the liquid to mimic cloth/satin.

I believe the person who created the animation I am talking about, probably used some sort of 3rd party plugin.. or is using a 3d package that can handle cloth dynamics much more efficiently than LW can.

01-15-2004, 10:51 AM
Yeah I agree, its gonna be a big render time as you are gonna need sub-dís and self collision to pull off the same detail for the effect.

I will post the file anyway just in case it helps anyone. The only thing on I changed from the setting I suggested in my previous post was I set the weight of the cloth to 20.

Maybe give Realflow a try as they have a 30 day demo out at the moment, and you should be able to get the results you want.

Good luck with your quest and donít forget to post some progress.

Rob T

01-15-2004, 10:57 AM

The MDD file is 8meg ziped...if you want it please email me at [email protected] and i'll be happy to send it

01-15-2004, 02:06 PM
Text objects are going to be a lot harder, this was done with a simple box, that makes it a lot less complex. Unless you can knock up some lo res proxy objects for your text, this could be a bit of a chugger.

Also, when the cloth hangs over the object, fade the object out. Fade it in as it gets revealed, it's much less hassle and you can worry less about little glitches.