correct cb weighting

#1

During the last 2 weeks I somehow figured out howto use mocca in the most important aspects. I was able to rig the woody model from frenchcinema and the mime character given with the manual. I now wanted to proceed to human characters and boom, there are the problems. All problems I found are caused by the wrong cb weighting. I followed some proposals telling me only to use it in absolute paint mode but there are still many problems of which I could only solve a few. For the worst one, I could find no help anywhere since all example rigs and rigging tuts are made for comic-like characters :

I used meg, because it was given with c4d xl8.5 and it was modeled really well for rigging it (refined “bend-areas”). [Don’t ask me why meg and not otto, I got some problems with his genitals and thought I’ll just shove them away 'til I solved the rest :)].
So the worst problem was (and for sure is) the area between the hips area and the upper leg. I always archieve annoying deformations in that area and don’t know how to solve that. I tried to gradiently lower the weighting in direction of the centeraxis and the hips, but that was useless. I don’t know what to do know and hope you can tell me something regarding that problem or maybe have an example weighted-rig for meg or otto (or similiar complex characters) laying around on you disk.

thx in advance, Richard “comastalker” Vock

#2

no idea…but i’d like to know some info on this…so excuse me whilst i attach myself to your thread and give it a bump at the same time.
cheers

#3

i cant find the button that says subscribe to this thread (i am not here you havent seen me :slight_smile:

#4

OK, so now it’s 4 of us who would like to see the answers to this (very good) question. :smiley:

#5

exactly 23 hours and 59 minutes after posting this thread I visit it and realize there are 3 responds; “well, maybe there’s some kind of help”.

False alarm.

At least I now see it’s not only my problem and that there IS a lack of explanation regarding the detailed use of complex weighting with cb.

any prophets out there showing us the way ?

#6

http://www.c4dcafe.com/portal/topic.asp?TOPIC_ID=491&FORUM_ID=7&CAT_ID=4&Topic_Title=bearing+gifts&Forum_Title=How+To%3A+Model

#7

there is also wolf_cub_one rig for mb…which uses cb so you could look at that…i think he has a new one also.

http://www.flingster.com/cgtalk/wolf_cub_one/otto%20mb%20rig.zip

#8

exactly the same file - and Cymru had lead me to believe he had rigged it himself tut tut :slight_smile:

#9

I’d like to offer an example file but I won’t have time to make one up until sometime next week.

#10

This is a problem that happens alot and the only way to realy overcome it is by building the mesh yourself with a clear idea of how you are going to animate it.

I had a look at the Otto rig Flingstar posted and that is badly weighted since it has the genitals weighted with the upper leg bone as oposed to the hips.

The way you should weight the lower body is anatomicaly.

The pelvis does not move when the legs move, so none of it should be weighted with the thigh bones.

Another thing is that real motion in the legs, as in walking, does only rotate the thigh bone by a few degrees so you find that often all the ugly deformations will not show on the animation because the take place outside the animations range of motion.

In short you need to build rigs that are driven by the animation requiements and not by any ideal, make your life easy.

My advice to you is to do more animation with simple rigs you have build with the Mime and Woody get a feel of how motion effects a simple rig/mesh and the then move to realistic figures. The leap from cartoon like figures to real humans is huge.

Also if you can get MotionBuilder drop the Meg character into it with a walk motion and you be surprised how small the rotations are and how little they effect the mesh.

regards

jannis

#11

cheers jannis…to be completely fair to the guy its not a final by any means he wanted it posting for feedback awhile ago unfortunately very few took him up on it…so afaik he has updated it for his own use but i don’t think he ever posted the final so some of these things he may have correct dunno…if wolf_cub_one is reading this maybe he can take time to comment on his findings etc. i mail him and let him know about your crits anyway as he was wanting some feedback…thanks bud.

Ric_535: heh heh to funny…

AdamT: if you get time to put something together i’d certainly like to see it.

#12

but walking ain’t all. If I for example just want my model to duck (take the character in splinter cell as an example-pose), even the mime character will bring me some really annoying problems, because the rotation angle is above 90 degree (and almost all game characters are able to duck). so I thought, there must be someone with a useful weighting setup, because you can’t get around a ducking feature and characters who only duck and run are really boring. I for sure understand that I should take a slow path and I besides do so, but I realize, the only problems I have is the weighting, the rest is a patience issue (you know, tweaking, tweaking and again… tweaking).

#13

The characters in splinter cell are all low poly count. To weight low poly count characters is very easy, since you don’t have the same deformation problems. The Otto and Meg meshes are not low poly count and they need alot more work to weight right.

I have somewhere a low poly character for a game I have made and used with Motionbuilder, I will find it and let you have it

regards

jannis

#14

Here is a movie with the overused kicks from Motionbuilder with the charecter mentioned above. She is a low poly character and you can see that the weighting is working no bad. By the way, the kicks are a very good test of testing extreme motion with weights

http://www.labelleart.com/temp/Output.mov

regards

jannis

#15

thx jannis, I’d really like to try some animation with this model (for sure completely non-commercial).

I mentioned the splinter-cell character as an example of a ducking pose, I didn’t say I’d like to make s splintercell-like figure, just that pose.

I’d still like to know how a good complex leg weighting looks like (for sure also the rest of the body, but I always start with the legs and also firstly got stuck with them).

btw, I already animated low-poly characters in extreme motions and I’m able to tell you that kicks AIN’T good to test extreme poses. You are able to animate them with a (relatively) bad bone setup (like the one used for the mime character). I myself am a passionate footbagger (well, “passionate” is redundant, since all footbaggers are passionate in their sport; check ftp://dl00013207:Gi1l3vw5@download.freepaq.dk/ryanpart2.avi as an example) and by the first try-outs always set myself the goal to be able to animate a footbagger. Even if you don’t do this sport, I propose you to try to animate some moves.

#16

Like all things there is an answer.

The trick to cb is in the modeling. Absolute or not is not the question. Your human model needs to be built with the idea of bend and fold. A perfect static model is useless. I was plagued by the Gumby effect until I got wise and re-built my joints.

In terms of cb…
I start with absolute and then paint in lower values to certain problem areas around the shoulders, elbow, knees and lower torso. Think stretch and fold. The elbow is a good example. If you have the humerus’s and the radius/ulna’s CBs both effecting/overlapping the geometry of the elbow it will bulge out when the arm is bent. In the noop, or dimple, of the arm you would want your CBs to “butt-up” against each other creating a crease or fold. Now if you have a big beefy man you will need to add more stabilizing bones. With these bones you paint certain effects here and there where needed. Where is the problem in this? It is on the sides of the arm that is neither bending nor folding. This is where careful modeling comes in. as to your specific question regarding the hips area and the upper leg it is all folding. You can virtually let the leg intersect the body from the outer hip all the way to the groin with only the lightest effect on the opposing geometry.

Don’t forget to think Hyper-nurbs. When i say “butt-up” I mean one point overlap.(one point fully selected 100% twice from two different bones) It is a pain but you will bet there if you stick with it.

What I am describing is not true-to-life but it is close enough if you are animating.

I am not willing to send out my models but I would be willing to send some of my process rends, QT and stills, illustrating what I am talking about if I have not explained my process clearly. As do not know how out how to post images and movies and I don’t really care to find out just yet you can email me and I would be happy to send you some of this and you would me more than welcome to forward them to the masses.

~Vale

#17

hey vale…i don’t suppose you could post a pic/screenshot of that elbow example if you have one knocking around?
cheers bud would appreciate it…

#18

I can’t believe someone claimed that my old Otto MB Rig was his. Thanks to Flingster for pointing me to this post. I do have a newer rig that is a lot better, but I can’t share that right now. If I do have the time, I’ll rig a low poly character and hopefully someone will post it for me.

#19

mail it me bud…and i’ll upload it for ya…then he can say he updated it to a new version…LOL
:applause:

#20

flingster and slim,
I just sent some images and animated gifs to both of you. I am not sure what will be most useful to you but feel free to post any of those images in this here thread for others if you like. It is easy enough for me to keep emailing them out as it is just a little stuffit archive on my web machine but in the name of discussion perhaps images would be nice for everyone.

Ciao,
~Vale