Smart Bone clothing interaction question.

[hammerjammer]

Hello All

In the photo below are 3 examples of a girl in a skirt or dress. The skirt in all three is at 50% opacity so that we can see the leg.



The first one is obviously a "leg at rest".
Picture A is with the leg whole leg raised.
Picture B is with the leg up and knee bent.
And in all three B1 is at the top and and B2 is below it.
By the way, I know you folks wish you had these drawing skills. Just kidding.

When creating a Smart Bone for picture "A", I just created a Smart bone labeled it B1 for the thigh. Rotated B1 and moved the points of the dress or skirt to match the leg (see picture A), pretty basic setup I guess.

So, My question is, When lifting the leg with the knee bent, How do I get the dress or skirt to look as seen in Picture "B"?
Using the same method from above in picture "A" doesn't work because the dress moves with the top bone "B1" even when the knee is bent. I tried to create a Smart Bone for the shin bone "B2" for the dress to follow. BUT then it always follows it even when it should not. I hope this makes sense to everyone. This is hard to explain.

HammerJammer

[sbtamu]

It should work. make sure you do note have some unwanted key frames in the actions also make sure that point on the bottom of the skirt is bound to the chin bone.

[heyvern]

I haven't found a perfect smart bone or "automatic" solution for this situation. In this type of situation I would simply create extra bones just for the dress and animate the bones "by hand" as needed to push the dress around.

For example the trouble I have is a walk cycle. The left and right legs switch sides but have the same effect on the dress. There's just no really easy way to use smart bones or constraints that will work. Whatever you do with those legs they will do their thing all the time. When that leg has reversed to the other side it should effect the back of the dress not the front. There's just no simple way to reverse the behavior of those bones.

So having bones just for the dress is the way to go.

There is a trick I use with bone constraints. It requires extra bones that have angle limits that move with one bone (like the thigh bone) but only in one direction and then it stops based on an angle limit so the dress or clothing doesn't follow all the way to the other side. You could then add smart bone vector movement to these secondary bones to adjust the dress. However this solution doesn't really deal with that "second bend" of the shin bone on the dress. Because that bone can bend when it's not even close to that side of the dress it will have the wrong effect. Also that same bone should also move the BACK of the dress in the same way.

The closest I've come to this is with trousers on a character. The "crotch" area of the pants. I create pants or trousers that have extra points in that area that are bound to bones with limits and constraints that leave one point behind and pull another forward at the crossing area. I think something like that would work for a dress, but it almost seems more trouble than it's worth. By the time you rig this you could simply animate dress bones by hand and avoid all the trouble .

[neeters_guy]

I haven't found a perfect smart bone or "automatic" solution for this situation. In this type of situation I would simply create extra bones just for the dress and animate the bones "by hand" as needed to push the dress around

This is pretty much what was suggested in this thread. Sometimes the best solution is knowing when not to use smart bones (or until "cloth simulation" comes to AS ).

[hammerjammer]

Heyvern

In this type of situation I would simply create extra bones just for the dress and animate the bones "by hand" as needed to push the dress around.

I did think of the extra bones just for the dress solution after a bit, because I remember seeing it done on other peoples rigs before. But I was convinced or should I say, I just wanted to do it with Smartbones. I guess that explains why I've seen it on other peoples rigs before. This is what I have been doing for the last 40 minutes, trying all kinds of stuff to get it to work and then I just gave up and saw yours and neeters_guy responses. I wish I would have seen them before wasting 40 minutes of my life on it. Oh well, Live and learn.

THANKS GUYS

HammerJammer

[hammerjammer]

I like setups on characters that automate things like the dress moving using smartbones and stuff. You know, things like, move one bone and a bunch of things happen.I like playing around and setting them up because I like all that technical behind the scenes stuff you got to do to make it work.

By the time you rig this you could simply animate dress bones by hand and avoid all the trouble .

I have been learning this sort of stuff the hard way. Like you said, most times all that setup time isn't really worth it. When it works its really fun though.

HammerJammer

[PirateX]

Hi from New York and looking for a skirt for such a smart legs. Please give an idea of the dress that looks good on smart legs?

[sillyanimate]

For me, I wouldn't bind points to skirt to the leg bone.
I would either do point animation or do smartbones controlling the skirt,