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Pate
08-12-2002, 06:08 PM
Hi again!

I just got my first character modeled, and am now attempting to bone it. I'm pretty happy with the way I got the fingers and wrist rigged (is that the correct term?), the elbow works so-so but I am really having trouble with the shoulder.

The biggest problem I currently have is that I don't quite understand how the Vertex Weights work. Anyways, some questions that have come to mind:

1) What is the difference between selecting a group of points, clicking on "Set Vertex Weight...", giving a weight of 50%, and then restricting a bone to this selection with a weight of 100%, and doing the above but swapping the percentages. Is there a difference?
2) If I have a Vertex Weight map with weights of 50% and I use this map to restrict a bone using a weight of 50% in the Restriction tag, does this mean the vertices move about 25% of the bone's movement?

I have had some results that make me think the weighting system does not work as I expect, which is why I ask..

3) Any helpful tips you can give me about what sort of vertex maps should I use in the shoulder area to get good looking mesh deformations?
4) Is there a tutorial that would explain the Vertex Weights really well? I have looked at the "Boning a hand" tutorial on the Maxon's pages, but it basically just says "most of the time you can use simple polygon selections, but in difficult cases, like the shoulder, a vertex weight map is needed".

I suppose I could wait for R8 with it's improved CA tools, but I'm too impatient! Besides, fighting with the current system will make me appreciate the new version more! :)

Thanks in advance!

Pate
Pate
08-12-2002, 06:30 PM
Oh, here's the model (don't mind the area from the neck up, it's a Poser Object and still temporary). The shoulders is reasonably OK with the arm bent downwards...
Pate
08-12-2002, 06:32 PM
... but not with the arm bent forward. :scream:
Grey
08-12-2002, 06:47 PM
I'd really like to know what the difference is between a vertex weightmap, a vertex selection and a point selection for the purposes of bones...

I've been using point selections...
matty2x4
08-12-2002, 08:49 PM
I have been having alsorts of bone and weight mapping troubles myself here is the link
http://www.cgtalk.com/showthread.php?s=&threadid=16574
Its true if you stick with it, it gets better I am still no expert and its still not working proprely yet... but I can see a faint glimmer at the end of the tunnel.
And yes I agree, it shouldnt be this hard to make things move... its what C4D is for after all.
Pate
08-13-2002, 04:40 AM
Thanks, Grey and matty2x4, for taking the time to reply!

Originally posted by Grey
I'd really like to know what the difference is between a vertex weightmap, a vertex selection and a point selection for the purposes of bones...

I've been using point selections...

Yeah, me too.. I would think this should be explained in the manual, but I haven't found the explanation either!

Trial and error gets rather frustrating when you have no idea why the bone restrictions behave the way they do.

I guess I just need to experiment further...

Pate
matty2x4
08-13-2002, 05:12 AM
this is kinda helpfull...
http://www.maxoncomputer.com/tutorial_detail.asp?tutorialID=74
Pate
08-13-2002, 02:14 PM
Originally posted by matty2x4
this is kinda helpfull...
http://www.maxoncomputer.com/tutorial_detail.asp?tutorialID=74

Thanks, I was aware of that (it's pretty much what I used when boning the hand of my figure). It says to accept the default settings (100% weight) for vertex weights, which leaves me wondering when should you use some other weight values! An inquiring mind wants to know more!!! :)

Pate
AdamT
08-13-2002, 03:28 PM
I don't think bone weights work the way they're supposed to in Cinema 7. I've done lots of tests combining different vertex weights and I found that:

* every vertex has to be 100% weighted to at least one bone or it will screw everything up;
* you can only get two (proper) results using vertex weights:
(1) if vertices on either side of a joint are assigned 100% to their respective bones, you will get one type of bend (sharp);
(2) if you try to soften the bend by assigning vertices 100% to one bone and then some percentage to the opposite bone, you will get a softer bend;
(3) if you vary the assigned weight for the opposing bone it makes no difference whatsoever--you get the same soft bend. Taking an elbow, for example: if you assign the first row of verts down from the elbow 100% to the forearm and 5% to the upper arm, you will get a softer bend. If you assign the same row 100% to the forearm and 95% to the upper arm, you get the exact same result.

Hopefully this has been fixed in v.8.
AdamT
08-13-2002, 03:32 PM
Matty,
It looks like the main problem with your rig is that some vertices aren't assigned 100% to some bone. Also, each bone in the rig should have a vmap restriction, even if it's empty. The latter could be your problem, too.
anobrin
08-13-2002, 11:16 PM
I used to build bone Rigs for imported poser meshes
but since poser got the free propack hosting plugin for cinema and lightwave i dont bother with the vertex mapping,restriction tag hassle any more:annoyed:

I just animate in poser and import to my C4DXL scene for rendering

http://66.70.166.29/promo/ghostae2.mpg
matty2x4
08-14-2002, 12:39 AM
who makes poser? www...:shrug:
Pate
08-14-2002, 04:36 AM
Originally posted by matty2x4
who makes poser? www...:shrug:

See www.curiouslabs.com (http://www.curiouslabs.com).

To anobrin: Yeah, I originally planned to do that as well (I have Poser + ProPack + the PzrForC4D plugin), but I need to have my character interact with the C4D scene (pick up objects etc) and I could not figure out how to easily do that. So, I thought I'd try using just a Poser head (for easy facial animation) and do the rest of the animation within C4D. Dunno if this will work properly, though, we shall see... Nice clip, btw! Reminds me of the "Ghost in the Shell" anime movie..

To AdamT: Many thanks for the pointers! Your observations pretty much explain all the strange behaviour I have noticed. I guess I need to restrict all the bones first, and then start tinkering with the individual vertex maps to get the desired result.

I'll post an update when I get something done, if you are interested...

Thanks for all your help!

Pate
anobrin
08-14-2002, 11:16 AM
Originally posted by Pate



To anobrin: Yeah, I originally planned to do that as well (I have Poser + ProPack + the PzrForC4D plugin), but I need to have my character interact with the C4D scene (pick up objects etc) and I could not figure out how to easily do that. So, I thought I'd try using just a Poser head (for easy facial animation) and do the rest of the animation within C4D. Dunno if this will work properly, though, we shall see... Nice clip, btw! Reminds me of the "Ghost in the Shell" anime movie..

Pate

Actually You Can .......................sort of
after you complete your animation in poserpro export the motion as a
BVH file.
Cinema Can import the BVH File as a set of pre-animated bones, of course performing the identical motion as your "file referenced" poserpropack person.
because this animated bone rig has a "physical" presence in the scene
once you move it inside your poser figure you brought inVIA the propack plugin
you can then attach camera targets ,nulls even hair dept. animated wigs
(See clips)
http://66.70.166.29/promo/DinoAE.mov

http://66.70.166.29/motions/walkAE.mpg

Curiouslabs didnt tell you about this in their PzrforC4D documentation because they did NOT know cinema4DXl can convert poser BVH motions to animated bone rigs until I told the company president in a phone conversation we had about me beta testing poser5 for MAC OSX.

anyway give it a shot
its working for me
Pate
08-14-2002, 01:52 PM
Wow!

Thanks anobrin for the tips, I had no idea you could do that!

I'll need to rethink my approach now..

You seem to be having a lot of interesting clips, hope you get your web site up soon, can't wait to see what else is there! :bounce: :thumbsup:

Pate
anobrin
08-14-2002, 03:53 PM
My website

http://www.customedia.net/
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