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sebbiej
05-12-2010, 07:13 PM
Hi, I'm trying to get an nCloth dress working on a character I've made... I've successfully got the character working in one shot on the animation I'm working on (the character file is referenced in to all my shots), but then the nCloth has got really messed up in another shot I'm doing.
I've followed the Maya tutorial to get where I am... and it works fine in the other shot I've done... But in this shot the constraints (point to surface) get really screwed up whenever I cache the mesh, as soon as it starts caching. Pic below better shows what I mean...

Mesh before:
http://farm4.static.flickr.com/3341/4601409685_6a66fa78e0_o.png

Mesh After:
http://farm5.static.flickr.com/4019/4602024648_ff528f6f52_o.png

And from the rear:
http://farm2.static.flickr.com/1124/4602025406_8cbd7d7b0d_o.png

As you can see, the mesh also gets quite deformed, and starts to penetrate the character mesh also! I've really got no idea on what is happening, or on how to fix it, but I really need to get it sorted ASAP as this project has to be handed in within 2 weeks time, so any help would be more than appreciated!

Thanks for your time, seb.

chandanG
05-20-2010, 07:04 PM
hi
are u constraining ur cloth with character geo??if yes then go to ur dynamic constraint attribute nd
enable the option EXTRUDE COLLISION might it will help.I also faced these kind of problem it worked for me

sebbiej
05-21-2010, 12:01 AM
Bump! Can anyone help with my problem, really, really need some help asap!!

chandanG
05-22-2010, 12:20 PM
Bump! Can anyone help with my problem, really, really need some help asap!!


hi,
is it possible to post ur file??

netsu
05-22-2010, 09:30 PM
Using the point to surface constraint can cause some problems. On simple shapes it can be effective but in this case it has gone a little crazy. Whenever creating nCloth clothing I usually use an entirely different method. Usually what I do is to first animate the dress as I would any other mesh. This could be really rough the idea is to just create a movement for the base mesh of the dress. So that it moves around with the characters. Once I have this movement done I just paint the input mesh attract to the area that needs to remain on the shoulders or anywhere else. The cloth will behave like cloth should in the areas painted black and the white areas will retain the original mesh animation prior to the nCloth creation. This is just a rough explanation of a way to fix this issue and to prevent it in further iterations of the project. So basically just painting input mesh attract values. If this is still unclear I can make an example video. Just let me know.

sebbiej
05-23-2010, 01:20 AM
Thanks for the replies everyone,

Netsu: I'll give this way a try in the future if I work with ncloth again, I haven't been able to get around the problem at the moment, and the project is due on tuesday so I haven't really got time to go back and re-do the cloth... I'm thinking tonight I'm going to just change the clothes to something simpler that will work with a warp deformer/binding it to the skeleton of the character, just to save time. Need to get it rendered off asap!

chandanG: Yeah the dress was constrained to the body using the point to surface constraint... I found a Exclude Collision option, but it didn't really do anything!

netsu
05-23-2010, 08:45 AM
It sucks you had such a short time to turn this around. I can fix something like that uber fast but I'm not going to put you in a touch spot. If you get a chance to upload it tomorrow go ahead and do so. Go ahead with your fix so that you can render it but I would still like to try to fix it for you for future reference.

mactoons
05-25-2010, 03:47 AM
Hi Netsu, I am interested in that workflow. What I tried to do was skin a characters shirt to the skeleton along with the character and then paint "Input Attract" where I wanted the cloth to simulate. There seems to be a problem though because I can only seem to get the cloth to either follow the skinning completely (by setting Input Attract to 1 in the attr ed) or not at all. It doesn't seem to take into account my painted values at all... any ideas?

newnimator
05-26-2010, 02:52 AM
Hi, for me the fastest way to fix that cloth on the shoulder is create a constrain geometry,

how to do it:
1. duplicate your cloth geometry, and delete all of the faces excluding the one on the shoulder.
2. wrap that duplicated geometry to the body so it will follow.
3. constrain your cloth to that geometry. so it will move the same way.
4 if it doesnt work, change it to weld, not spring. or exclude collision.

TIP: try not to constrain/point to surface your cloth to the body because it has different topology.

I hope this helps.

john_homer
05-26-2010, 06:33 AM
I would suggest looking into why you have the problem rather than looking for a workaround.

you are doing something wrong, looking at your mesh, the constraints are not the only problem, you also have collision and stretch/compression issues
if you want to get better and not have these problems in the future you should work out why

you need to post the scene to get your answer

faking cloth will always look like faked cloth.

imputMeshAttract (even if it worked) is for effects and shot specific manipulation etc, not general setup of cloth garments like a dress
simming partial meshes always adds more issues, they have solutions, but they are more complicated to solve than your current issues...

well, thats my opinion ;)

.j

john_homer
05-26-2010, 06:36 AM
TIP: try not to constrain/point to surface your cloth to the body because it has different topology.

having different typology is no issue with a point to surface constraint, I do this all day long (since nCloth was released)

.j

newnimator
05-26-2010, 10:01 AM
having different typology is no issue with a point to surface constraint, I do this all day long (since nCloth was released)

.j

nope nope. if theres a "fall off" on your shoulder that you want to move. there will be an issue. if its 100% pinned. i guess its fine. for me its better to constrain on the same mesh as the cloth so the cloth will not be confused where to go. =)

chandanG
05-26-2010, 07:53 PM
Hi Netsu, I am interested in that workflow. What I tried to do was skin a characters shirt to the skeleton along with the character and then paint "Input Attract" where I wanted the cloth to simulate. There seems to be a problem though because I can only seem to get the cloth to either follow the skinning completely (by setting Input Attract to 1 in the attr ed) or not at all. It doesn't seem to take into account my painted values at all... any ideas?

Hi mac,
If i m getting u right ,u hv skinned a shirt with the character skeleton nd its going along with the character..right??if it is so,wht u can do is create a dublicate of ur shirt geo,delete history of dublicate one nd wrap it with ur skinnedshirt nd take a geometry cache(u can also take geometry cache directly but sometimes it doesnt come).After tht delete the history of dublicate one,assign the geometry cache to dublicate shirt nd apply ncloth,after tht make ur input mesh attract 1 nd paint ur input mesh according to wht area u want to simulate nd wht u want to be as skinned one.I always use this,when i get problem with the constraints..

Thanks

john_homer
05-27-2010, 01:02 AM
nope nope. if theres a "fall off" on your shoulder that you want to move. there will be an issue. if its 100% pinned. i guess its fine. for me its better to constrain on the same mesh as the cloth so the cloth will not be confused where to go. =)

I really dont know what you are talking about, maybe there is confusion here.
but a point to surface constraint will happily constrain nCloth verts to any surface, no matter the typology otherwise it would be pointless

.j

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