The Amazing rubber bulge
Sky Hndx
Posts: 142
I’ve been making anatomically correct trousers for some male characters. Nothing overly pronounced or exaggerated, just what should normally be there so the guy doesn’t look like a Ken doll or a Sears catalog model. Thing is after turning the trousers into conforming clothing the geometry in the bulge area gets assigned to the left and right thigh. When I pose the legs the bulge becomes elongated and distorted so much it begins to look very unusual. (Kinda like the guy is more than just happy to see ya).
So what I did was create a shading domain in Hexagon for the bulge then created a face group out of that in DS. After the trousers get rigged I selected the bulge face group and attenuate it set at 0%. The first time I did that the stretched out bugle sprang back into its normal shape (…in my head I went “sproing”). Then tidied it up with the smooth brush in the node weight map brush.
Is this just one way to handle the situation? It seems like a bit much just for a bulge. I figured I’d have to do this if I ever decided to create form fitting swimwear or underwear for a character. I suppose I could have just used the deformer but I’m trying my hand at creating realistic folds and creases in clothing and thought the deformer would have stretched the texture and made the area look odd.
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Comments
Download sculptris alpha and use that to manually sculpt it. It's not very good for traditional structured modeling, but for little detail bits like this it's perfect. I made a unzip morph for a leather jacket with it using just the pull and smooth tools.
The grow tool could make the bulge, smooth it as you want and carefully use the crease tool to create the wrinkles you want.
It's extremely simple and intuitive.
Yes, it is a perennially difficult area. All of my male products have to have special JCM to bend properly with a "normal" bulge.
How exactly have you set up the point where the left and right leg meshes come together? The hip mesh should always come down all the way to separate the legs — it sounds like you've got a bit where the left and right legs come into direct contact, which is known to cause Weird Stuff™ to happen.
IIRC it's due to the way body parts have to be set up; every child part must have only one parent part, e.g. from the foot up to the hip. If the hip doesn't separate the legs, that violates the rule as each thigh will have two parents, the hip and the other thigh.
How exactly have you set up the point where the left and right leg meshes come together? The hip mesh should always come down all the way to separate the legs — it sounds like you've got a bit where the left and right legs come into direct contact, which is known to cause Weird Stuff™ to happen.
IIRC it's due to the way body parts have to be set up; every child part must have only one parent part, e.g. from the foot up to the hip. If the hip doesn't separate the legs, that violates the rule as each thigh will have two parents, the hip and the other thigh.
What I meant by assigning was that the transfer utility was causing the bulge area in the center of the hip to be influenced by the weight maps of the thighs. When I checked the area in the node weight map brush I saw the red from both thighs extended to the bulge. Which is why I created the bulge face group and attenuated it so it would no longer stretch when the thighs were posed. I just wasn't that clear in my explanation.
Thanks much, I'll look into it.
How exactly have you set up the point where the left and right leg meshes come together? The hip mesh should always come down all the way to separate the legs — it sounds like you've got a bit where the left and right legs come into direct contact, which is known to cause Weird Stuff™ to happen.
IIRC it's due to the way body parts have to be set up; every child part must have only one parent part, e.g. from the foot up to the hip. If the hip doesn't separate the legs, that violates the rule as each thigh will have two parents, the hip and the other thigh.
In legacy/Poser rigging that's true -a group may be connected only to its parent and its children, not siblings or other groups. But with TriAx rigging the groups are not functional for rigging - they just make it easier to assign the bones and initial weight maps when doing a new figure, and allow for selection in the viewport - and there's no requirement for weights to obey the same rules as legacy groups.