dress movement

basshole · Post by **basshole** » Fri Aug 29, 2008 11:47 pm

I've searched through the other dress-based threads on here, but haven't seen anything quite like what I'm about to ask.

So, I have a character wearing a dress (a woman), and I have a problem. I can arrange it so the dress tracks with the legs by simply point binding the bones, but the issue is, what if one leg crosses in front of the other one? For instance, if the character is facing left (in a 3/4 or profile angle) the way I've drawn/rigged her), her right leg (the "back" leg from this angle, or the leg that's farther away from the "camera") can move all the way forward, no problem, but if it goes back too far and crosses her left leg, I get holes in the dress at it's bottom. This is partly because some points on the bottom of the dress are bound to the left leg, and some to the right. When those points cross over each other, problems.

A worse problem occurs if I try to move the left leg, the front leg from this angle, forward. It can go all the way back, no problem, but if I move that leg forward, and it crosses the right, the whole thing goes to hell. The whole dress becomes a squiggly hole-infested mess. Is there a relatively simple solution? Or should I just keep those legs from crossing?

chucky · Post by **chucky** » Sat Aug 30, 2008 12:11 am

Hey bass'
I have run into this one and there is a great way round it.
Use vern,s aim bone script.

This works a treat, it will keep the skirt from tearing or running past the other leg.

The Ghoulie is from a project I'm messing with called BITE CLUB
http://pc.celtx.com/project/7esgSezmrp5B
feel free to check it out.

basshole · Post by **basshole** » Sat Aug 30, 2008 12:45 am

Thanks. It's amazing how when anyone here posts their work, it looks so much more professional than mine. OH well.

Okay, I've looked at the script and instructions/description for it, and, sorry to sound thick here, but how do you use this to solve our problem?

slowtiger · Post by **slowtiger** » Sat Aug 30, 2008 1:24 am

bass: Maybe you should tell us wether it's a tight dress like chucky's, or the wide swinging variety because they need to be treated differently. A picture would help.

Wide dress: From my very limited experiments with that I found that a separate bone chain for the dress, starting at the hips, was best. No connection to the legs.

Tight dress: Haven't tested this, but an idea comes to mind. As long as you use plain fill colours and outlines, it would be possible to have 2 separate shapes forming the skirt, one attached to each leg, and just 1 extra outline which connects to both legs. This way the shapes will overlap while your legs cross, but they will show no gap. The outline will stay be just a line, no matter how it winds in itself.

chucky · Post by **chucky** » Sat Aug 30, 2008 1:27 am

of course you don't have to connect to the leg you could hang the bone off a dynamically swinging bone on a flowing dress if you like.

basshole · Post by **basshole** » Sat Aug 30, 2008 2:40 am

Oh my God. . .the separate bone chain for the dress is so simple it's brilliant. I'll have to look into that. Yes, it is a looser, longer dress.

Okay, as I think about it, I have a few questions. . .

are talking a separate bone layer, or part of the same skeleton as the rest of the figure?

Seems like if I built a string of bones along the dress border, and could some how have it be controlled (via angle control bone) by the movement of the legs, that would work, yes?

slowtiger · Post by **slowtiger** » Sat Aug 30, 2008 5:57 am

Dress bones in the same bone layer as the body is OK. I'd recommend against connecting it in any way to the legs, as the swinging dress has some lag: it moves a moment later than the legs, depending on length and weight of the dress. But for those inclined to do so maybe some dampened spring physics may apply ...

basshole · Post by **basshole** » Sat Aug 30, 2008 1:34 pm

So I would then have to animate the legs completely separate from the dress? In other words, first move legs, then move dress to make it appear to match movement of legs?

basshole · Post by **basshole** » Sat Aug 30, 2008 1:34 pm

So I would then have to animate the legs completely separate from the dress? In other words, first move legs, then move dress to make it appear to match movement of legs?

slowtiger · Post by **slowtiger** » Sat Aug 30, 2008 2:53 pm

Definitely. A dress is "secondary movement", which means you do the primary movement first (the walk), then go back to start of scene and do the secondary stuff.

basshole · Post by **basshole** » Sat Aug 30, 2008 2:58 pm

Oy. Okay. I try it either that way, or the lazier way of having the secondary movement somehow directly controlled by the primary.

basshole · Post by **basshole** » Sat Aug 30, 2008 9:46 pm

Chucky, I was wondering if you'd be willing to post an actual project file with that female character, so I could see how the hip and shoulder bones work by playing with them, and see if it's worth a significant investment of time to retrofit all the characters I've created so far with such a skeletal structure. They way they're all built now, the torso is basically controlled by three vertical bones (a spine, if you will), and the arms and leg bones are just sort of floating off in space where they go, instead of actually having "shoulders" or a "pelvis" connecting them to the "spine". I thought it was fine (and it is), but your character has made me curious.

chucky · Post by **chucky** » Sat Aug 30, 2008 11:19 pm

I've actually slightly adapted and added to the rig that has been discussed in Vern's load and save bone animation.
This way I might be able standardise as much as possible to a generic rig structure.
You will notice I should actually tweak her shoulders a bit.Maybe I have used an old version for the skirt demo.
I just like using shoulder and hip bones, after all, we have shoulders and hips.

http://www.lowrestv.com/anime_studio/bo ... leton.anme
This is actually Vern ( the champ)'s original file that I based the rig off, it might be useful especially when it comes to load save and swapping bone animation.It may be wiser to start from here rather than my altered rig.

basshole · Post by **basshole** » Sun Aug 31, 2008 12:25 am

Thanks. I guess I wanted to see yours 'cause it had flesh/vector layers, instead of just being a skeleton, and I wanted to see how you rigged those hips/shoulders to the vectors.

For instance, for my characters, I went against the conventional wisdom and put a lot of things on separate vector layers that most of you guys don't seem to. The upper arm and lower arm, for example, are separate vector layers, so that I didn't have to deal with the deformation issue when the arm bends. Ditto the legs. I meticulously tweaked the adjoining ends of the upper and lower arms so that the lines are smooth as each limb goes through its entire range of motion.

So, in your example, I was just curious to see how you handled all that with the extra bones and how they attached to the various layers.

I was also thinking that maybe for the hips, since in reality, the pelvis is a single bone, I could make the right and left hip bones (if I go through with all this) act as one bone together when either was tweaked. . .maybe link them together, make the left bone be the right bone's angle control bone, and vice versa, so that when you move one up or down, the other moves in tandem, in the opposite direction (like a see saw).

heyvern · Post by **heyvern** » Sun Aug 31, 2008 5:39 am

chucky wrote:I've actually slightly adapted and added to the rig that has been discussed in Vern's load and save bone animation.
This way I might be able standardise as much as possible to a generic rig structure.

Good grief. Never thought of that. Use the same bone animation for clothes in a separate bone layer!

I've found that flowing clothes like dresses work much better using flexible bone binding than region binding. the trouble has always been how to use two types of bone binding with clothes. The only solution was to use a separate bone layer just for a dress or shirt etc. With saved animation you could just load the same file into the clothes bone layer... doesn't solve layering though.

------

By the way... save and load animation script is working pretty slick. Still testing it and trying to work out some bugs with bone rotation/translation offsets on different (but similar) rigs.

The action saving and loading works perfectly and I added the ability to load any animation directly to a named action. That... was... a freaking... nightmare. Oh lordy lordy hallelujah. Yea, though I HAVE walked through the valley of the shadow of death, I will fear no evil... but get those freaking lua tables out of my face! almost went insane thank you very much.

-vern