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JacquesD
07-03-2003, 03:42 PM
I've started rigging my last character but I'm not that good at animation/rigging so I thought I might get so help from the animation gurus.
Here's a print of the character in stance and pose:
http://users.skynet.be/fa008785/RigPose_a.jpg

I'll of course correct all the deformations with morphs but I'd like it to be as good as possible before starting these corrections.

Could any of you guys tip me a bit about some bones positions for best deformations or any others things I might have to do to get a better result?

Thanks.

Eugeny
07-03-2003, 04:04 PM
It's looks pretty OK (for me) with existing deformations ...
Do u use weight maps or it's only bones falloff ?

Triple G
07-03-2003, 04:08 PM
I agree...it doesn't look bad to me. I might try moving the shoulder joints up just a bit. Then probably just a bit of weight map tweaking (crotch and neck in particular) and you should be pretty well off. :)

JacquesD
07-03-2003, 05:52 PM
Thanks Eugeny but I don't want it to be 'Ok'... I'd like it to be really really good... if that's possible of course.

Thanks Triple G... that's the kind of things I'd like to know... specially about the shoulders... is there a position for the bones which work most of the time?... that kind of tips.

I know I could find it myself by trying again and over again but that'd be cool if I could use some help from people who already experienced it many times.

Thanks. ;)

Castius
07-03-2003, 06:53 PM
I would suggest researching motion capture skeleton setups. These are important because there bones need to be correct for the animation to playback correctly. This is where I found the most detailed information on joint position. Your deformation looks ok but your skeleton looks like it's to uniform. legs for strait down arm go strait out. In reality your skeleton is barely strait. Strait is better for IK not deformation. Good luck, looks like a great start.

You can rest your bone on 0 frame and use -1 to setup repose bones and for ik.

fastfinger
07-03-2003, 07:01 PM
The bones below the knees doesnt have to be straight.
And the center of Mass could be 1~3cm below the umbilicus not the pelvis.

carnera
07-03-2003, 07:24 PM
i would add some extra bones to stabilize the shoulders...
but the model looks great.. ;)

Freebooter
07-04-2003, 10:02 AM
Hi ripper,

had a couple of goes at this post now, but I'm hoping this one will make it up...

Your model looks real good, and should bend fine....

Now, about them shoulders:

Shoulders are one of the hardest bits to get right, here's what I would do.

First of all, you want to drop the Da Vinci pose. Put his arms into a more comfortable, natural position. Unless you're planning on recreating the "flying" scene from Tianic, your model will hardly ever find himself in this pose during animation. :) Set them to about 45-degrees down, so that they are out from the body, but in a comfortable way. Bend the elbows a bit too, so that the geometry holds its shape during deformation.

Run the clavicle bones to the beginning of the shoulder area proper. They are there to give a *little* lift to the shoulder as a whole, but the main work will be done by the small bone at the end of the shoulder that connects the clavicle with the upperarm bone. this bone gives the little bit of lift when the arm is moved up and also sets the pitch axis for the arm below it. Be careful with this fellow, 'cos he is real important.

You might want also to add a small bone to the torso in the armpit area to hold the geometry there so that the armpit doesn't collapse, but as you're using LW, weightmaps can do a lot of this work.

I've done a rough overpaint to show what I'm meaning here, I'll also try and post a couple of other examples that might help.

N

Freebooter
07-04-2003, 10:03 AM
Attachment didn't take, here it is again.

N

Freebooter
07-04-2003, 10:13 AM
Okay, here's one from one of my rigs.

The image is from Messiah, but the philosophy is still there.

Lightwave will let you seperate the bones like this, but it can be quirky. Personally I don't use skelegons when rigging in LW, but AFAIK it shouldn't matter what route you use to get the bones in there.

Once you've set the positions, you can decrease the rest-length of the bones to govern their effect on the area. It works well, though MAY NOT BE NECESSARY for what you are wanting, esp as you have the weightmap tools and said you would be using morphs to correct.

anyway, hope this is a help for you.

N

JacquesD
07-04-2003, 10:54 AM
Thanks for your help guys!

Freebooter: thanks for your explanation... interesting stuffs but I'm going to use mocap clips from Motion Builder and I need my skeleton to be in that rest position.

I did a quick test with joint morph on his right shoulder... I think with some more tweaking, that's going to work.

Joint Morph test (http://users.skynet.be/fa008785/ShoulderTest_001.avi)

Thanks again.

PS:Latest divX required

Steve Warner
07-04-2003, 06:36 PM
Holy freaking smokes, that's tight! I don't have anything productive to add, but I just wanted to say this looks outstanding. :thumbsup:

Keep up the awesome work!

Steve

webfox
07-04-2003, 06:43 PM
It looks really good. I'd add more bones to the neck so that when he looks up, his neck doesn't seem stiff.

I struggle with rigging, too. Wish I could offer more.

Your modeling is amazing, though. Even offset abs!

You have classical art training, right?

PolyMangler
07-04-2003, 06:51 PM
awesome model man :eek: i'm experianced only in the slightest when it comes to rigging but i did read an article in 3dworld on human rigging and it made some good points on common mistakes people make..here's the ones i remember off the top of my head

1)connecting the coller bone directly to the base of the arm....they suggested putting in a small in-between bone that connected to teh collar at the top and went down to start teh arm makin a lil zig-zag shape in the bones...this is suppose to give you a lil greater control over shoulder deformation and realism

2) the legs and arms are not straight, as most of us make them. They are slightly offset so that they "roll" just a little when they are rotated....if you rotate your forearm back and forth you can see what they're refering too and how to recreate it

anyway that may help may not but like i said i haven't had much pratice at it myself...

again awesome model.....how long did it take you and how did you go about building it?

SplineGod
07-04-2003, 07:07 PM
Personally I find that how the character was modeled has a big effect on how well it deforms and no amount of weight mapping or hold bones seems to help much.
Its also very difficult to know what to tweak until you figure out from your storyboards what sorts of things the character must be able to do. Put him in the most extreme poses youll encounter. From there you can determine what needs to be fixed.
I would play around with several things(in no particular order) before going on to weight maps:
1. Joint positions
2. Hold bones
3. Bone falloff (^64, ^128 gives tighter results)
4. Adjust rest length AFTER resting bones. You can see geometry grabbed or released as you change this.
5. Bone strength/multiply by rest length
6. Break single bones into 2 or more bones to distribute twisting. This works well in more areas then just the forearms.
7. Bone Orientation. People seem to always set up bones to match the way bones are oriented in real people. 3D bones are not at all like real bones. LW bones are a special case of lattice deformers - you put them in and they work. Orienting bones in creative ways can yield unexpected results.Turning some bones off and leaving others on can give interesting results.

If you do go with weight maps keep them simple.
Another thing I would look at is the Ortho Pak from HERE (http://www.irrationalnumber.com) .
It allows you do manipulate bones directly in layout like skelegons (and more). You dont have to jump back and forth between layout and modeler to tweak bones. They have a 30 day demo version.
Your model looks great but as I said you wont be able to tell what you really need to do until you pose it.

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