Weighting Problem

[Adam Trachtenberg]

This is why it’s a bad idea to use very heavy meshes for character animation. I would try to builder a lighter mesh on top of the existing model using the create polygon tool in quadrangle strip mode in conjunction with polygon snapping.

[Trevor Gent]

Thanks Adam,

So I guess you’re telling me that I’ve really just painted myself into a corner on this one? :O

Ideally, I wanted to have quite of bit of detail in my models face. I used a lot of subdivisions only in the face because I wasn’t getting the result I wanted out of displacement/bump mapping. So here I am.

It just seems strange. I’ve weighted and corrected all the limbs with no troubles. But when it comes to the high density areas I run into problems. (Even though it seems to be the same operation. Just on a larger scale)

I am definitely taking heed of your suggestions but I also want to try a few more things before I go back to re-modelling (again!)

Here’s my new angle:

I’ve tried using the weight/brush tool to select the vertices that need to follow as I move the goal IK but it seems they either get too much or too little weight applied.(distorting the face even more) Is there some way I can equalize the weight so that all the vertices in the model’s head get an equal amount of weight? So that when I move the IK the entire head moves as one?

I’ve looked into the “bleed” function of the weight tool but so far this appears to do the exact same thing as “Add”. Either adds too much or too little weight.

Any thoughts?

Much appreciated.

Trevor Gent

[Trevor Gent]

Yee Haww!

So simple if it was a dog it would have bit me!

I just cranked up the strength of the weight/brush tool to 100% and set it to erase. Then I erased ALL weighting and re-weighted “by hand”. A bit of a mess-around but it seems to have done the trick.

Sorry to be a pain but I’m still kind of new to all this.

Thanks again!

[Adam Trachtenberg]

Cool, I’m glad you worked it out.

Generally the way people handle this is to create a lower resolution mesh, weight and animate that, and put it in a HyperNurbs object to smooth it out.

[Trevor Gent]

Thanks Adam,

I sure wish I talked to you before I started all this!

I’ve been messing around with c4d for about 3 months and only just recently got into rigging.

So from what you’ve told me I should animate everything before adding fine details to my model? Does this include “accessory” details like hair, clothing etc?

Not having a problem with modeling (thanks, Art Classes) but finding rigging/binding/weighting a bit more of a challenge to wrap my head around. Still, I am making progress after ditching a set of tutorials that was more or less steering me in several wrong directions.
I’ve used other training tutorials from the same company and found them fairly thorough. But their C4D offerings are VERY general at best. ( I won’t name names but my girlfriend, Lynda, totally agrees with me!) 😉

Thanks again.

[Adam Trachtenberg]

Well, you have to complete the model before you begin weighting. Otherwise you’ll just end up having to redo a lot of work. What I’m talking about is just using the minimum number of polygons to create the detail you need, and then using the HN object to smooth it out. Check out the Fred and Lisa models that come in the presets for some pretty good examples.

[Trevor Gent]

Thanks once again Adam. I really appreciate all your help.

I will definitely check the preset models out.

I guess weighting is something thatI just have to get the feel for. There’s just not a lot of in depth documentation on the subject.

I am finding some areas are easier to work on than others.

The models arm for instance I’m finding to be a real pain. I’m trying my best to blend the weight so that when the arm is rotated there is no stretching or warping. So far have only been only moderately successful!

Any tips? Or is it a trial and error/ keep trying till you get it right sort of thing? I’ll be happy either way but even more so if there was an easier way!

Thanks again

Trev

[Adam Trachtenberg]

The key, in my opinion, is to use a very low strength setting with the weight tool — like 1-2% — and make gradual changes. It helps a lot to move the IK goals so that you get the undesirable deformation and then use the weight tool to straighten it out as best you can (keyframe your goal positions first).

If you want to get fancy you can use morphs to help correct deformations. Then you can either animate the morphs by hand or set up Xpresso controls to drive them. So in the case of the elbow you’d use the distance between the goal and the shoulder to drive a morph.

The difficulty there is that it’s tricky adjusting the mesh in a deformed state. You can turn on deformed editing in the viewport configuration dialogue, but points don’t move the way you’d expect them to when they’re being deformed.

[Trevor Gent]

Thanks very much Adam!

Will put your tips into effect shortly!

I’m definately learning from my mistakes and your first suggestion (using a lower poly mesh) is one that I’m sure I will remember in the future!

Thanks again for all your help!

Trev