Real bones vs. CG bones...

[JasonOsipa]

cg bones are completely unrelated to real bones, and the assumption that matching size/shape/orientation closely would yield best or even good results is flawed.

With a muscle system in place, that comment is withdrawn, but in general, i find people have MORE problems getting good deformation out of "accurate" bone placement than not.

[PEN]

cg bones are completely unrelated to real bones, and the assumption that matching size/shape/orientation closely would yield best or even good results is flawed.

With a muscle system in place, that comment is withdrawn, but in general, i find people have MORE problems getting good deformation out of "accurate" bone placement than not.
I agree with this a 100%, when rigging without a 100% real muscle, tendon system trying to use "real" bones will not get you a real looking character.

Ever muscle systems are never perfect is done as a real setup and need to be made to just work and look real in the end solution. There is alot going on under our skin that I don't think we can begine to calculate that this point.

[Dimebag]

Did they ever thought about putting real bone geometry in complexe cg muscle systems? Instead of just creating two simple linked abtract points with a so call "pivot point"? It's just too easy...

[BowlofSoup]

I must Agree with Jason on this one. With my mechanical engineering background oriented towards the biomechanical field, my opinion is that real motion is very much more dependant on the nature of the musculature involved. Bones will serve in restricting motion, but are mainly for support.
For the 3D/CG aspect, well it comes down to what you are going to see in the end product, if you're showing a still of the rig, then yeah 2 bones won't suffice. Guess you'll just have to try it out and see what bone ratio will give you the motion you like. I doubt I have to tell you that often animating is about subtle exageration and being able to things you can't with human actors. So maybe those 24 bones could get interesting. Althought I doubt anyone will tell the difference between 15 and 24 if they are covered in muscle and skin.
Then again, that's just my opinion.

Cheers

Adam.

[michaelb]

Sorry it took so long for me to get back again. Thank you for your insights, I appreciate them. I was wondering about something else over the weekend. Does anyone know how many spine bones they used to set up the Gollum rig in LOTR? I remember seeing a motion capture session with the actor's motion being reflected in a real-time feedback rig, and they obviously did not put markers on his back for every one of his 24 moveable vertebrea. :) I was curious about the actual setup used there. Any ideas about that?

[eek]

Getting the character to move well, articulate properly is the key. If it requires 12 bone then put 12 in. It really depends on what you want your character to do. Ive taken a look at some of the gollum rigs(in clips), the version i saw had the torso chopped up into 8 parts, which had a spine setup similiar to mine.

Ive also seen clips of a complete bone/muscle and skin setup of gollum climbing down a wall.
And i had a lot of veterbra over 12 i rekon.

eek

[Terkonn]

I agree with what was said above, do you mind posting a render?

[seven6ty]

Another thing I thought I'd mention, it's probably more helpful to try matching the number of vertebrae to the lines of detail on your model. If you have, say 10 lines of detail going around your rib cage, it makes no sense to have say, 15 joints in that area. For an elephant rig I did, I had 13 lines of vertices going up and down the length of the trunk. So I wanted to have one joine for each line of detail so that it could make it move with the joint. Then I just made a spline IK control for it, and was able to make clusters of the 13 or so resulting CV's, to simplify it enough that I got about 5 clusters out of that. Anyways, just thought I'd throw that in there as well.

[michaelb]

Sorry I can't show any renders at this time. I'm just trying to understand the general concepts before I try to incorporate them into a rig. It will have to be close anatomically because my first efforts will be focused on hi-res printing, and it will have to look good close up. Thanks for all the insights. I appreciate them. :)

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