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MarkInTx
03-25-2008, 03:08 AM
Quick Question before I Start hacking away...

I have a mesh that I rigged using AutoRigger. Seems like everything worked OK (meaning I put the bones in the right place...)

But, when I move the arms, I am getting unsightly bulges in the breast area. (See attached)

My question is: A) Does that mean I should redo the autorigging process and reposition the bones because I didn't get it right the first time or B) It is doing what is expected, and now I need to add more detail to the rig to fix this stuff.

And if B, I am assuming I just need to add place holder bones...right? Or do I need to somehow constrain the joint so it can't move that far?

Thanks for pointing me in the right direction...

Before:


http://www.digitalartistguild.com/Tests/Messiah/MS3_SS1.jpg

AFTER:

http://www.digitalartistguild.com/Tests/Messiah/MS3_SS2.jpg

Bugpoo
03-25-2008, 07:42 AM
1) Your clavicle bone placement looks too high just looking at the geometry on your model (clavicle bumps).
2) Which controller are you rotating the arm with? The shoulder should be doing the majority of the rotation, not the clavicle

3) Hold bones would help the arm pits and breast/rib cage area, but it looks more like the wrong armature is being animated...just guessing from the pic

MarkInTx
03-25-2008, 10:42 AM
1) Your clavicle bone placement looks too high just looking at the geometry on your model (clavicle bumps).
2) Which controller are you rotating the arm with? The shoulder should be doing the majority of the rotation, not the clavicle

3) Hold bones would help the arm pits and breast/rib cage area, but it looks more like the wrong armature is being animated...just guessing from the pic

Thanks for the look. I'll try reworking some of the placement.

As for the controller, I am grabbing the dot there at the shoulder and moving it... isn't that the shoulder controller?

Ulven
03-25-2008, 03:27 PM
I think for that character I would place the base of the clavicle bone further out towards the shoulder on X (almost half way) and further down on Y and have a hold bone going from the spine to this bone.

MarkInTx
03-25-2008, 08:53 PM
I think for that character I would place the base of the clavicle bone further out towards the shoulder on X (almost half way) and further down on Y and have a hold bone going from the spine to this bone.

There's no benefit to going back to the beginning and diong this, is there?

I mean, I might as well just tweak the rig AFTER running the autorig plugin... right?

MarkInTx
03-25-2008, 08:55 PM
I think for that character I would place the base of the clavicle bone further out towards the shoulder on X (almost half way) and further down on Y and have a hold bone going from the spine to this bone.

OK. I'll give that a whack..

I'm not sure what all your plug-in takes into account when making the rig... There's no benefit to going back to the beginning and doing this from the start, is there?

I mean, I might as well just tweak the rig AFTER running the autorig plugin... right?

Ulven
03-25-2008, 10:30 PM
Yeah for this kind of small change there's little to no benefit in doing it before the autorig button is hit. Parent any children of the clavicle to something else using keep position and keep rotation, move and change the clavicle, then parent the rest of the arm back in place (and maybe adjust the arm if you so please). Afterwards check that the children of the clavicle arm bone is at 0.0 on eggs and why (no need to check zed), type it into the field in setup mode if it's slightly off. use fix symmetry to fix it up on the other side.

lanosrep1
03-25-2008, 11:46 PM
Wondering how much detail the model has.. As the way bones in Messiah works best is with low poly models. If you have very few bones.. like the autorigger, then the bones will grab a larger area.. and when you have a high poly mesh, you can run into influence issues.. Using more bones can sometimes help... sometimes it makes the deformation more difficult to control.. just a thought..
G.

MarkInTx
03-26-2008, 01:30 AM
Wondering how much detail the model has.. As the way bones in Messiah works best is with low poly models. If you have very few bones.. like the autorigger, then the bones will grab a larger area.. and when you have a high poly mesh, you can run into influence issues.. Using more bones can sometimes help... sometimes it makes the deformation more difficult to control.. just a thought..
G.

Well, you are hitting all of my insecurities now... yikes...

OK... Model is mine, so I am not SURE it is a good one.

She has about 3800 polys, though about 1500 of those are in the head and face area. All Quads... I THINK decent ploy flow.

Is this bad to use? (Wires attached)

http://www.digitalartistguild.com/Tests/Messiah/bustwires.jpg


http://www.digitalartistguild.com/Tests/Messiah/bodywires.jpg

http://www.digitalartistguild.com/Tests/Messiah/bodywires2.jpg

MarkInTx
03-26-2008, 01:43 AM
PLease bear with me... I know I can be dense... but trying to make sure I understand not only what you are saying... but why...

1. I unparent the children of the clavicle -- which is a bunch of nulls and the upper and lower arm, hand, etc.
2. Parent those bones to something (anything) else, but make sure they keep all of their other settings (besides their parent).
3. Move the Clavicle to a better position
4. Add a hold bone that runs up and down... basically perpendicular to the clavicle (or maybe a slight angle inwards)
5. Parent this to the spine -- OK, WHICH spine? The Null Spine_PVT? Or does it matter?
6. Move the other bones back to parented to the clavicle.

So... that whole moving bones to a new parent was just so I didn't have to tweak all of the other bones one by one after moving the clavicle (because their position is basically all right?) Or is there some other subtle purpose for that?

Also... (you Brits!) I am assuming that eggs = X, why = Y and zed = Z?






I think for that character I would place the base of the clavicle bone further out towards the shoulder on X (almost half way) and further down on Y and have a hold bone going from the spine to this bone.

Yeah for this kind of small change there's little to no benefit in doing it before the autorig button is hit. Parent any children of the clavicle to something else using keep position and keep rotation, move and change the clavicle, then parent the rest of the arm back in place (and maybe adjust the arm if you so please). Afterwards check that the children of the clavicle arm bone is at 0.0 on eggs and why (no need to check zed), type it into the field in setup mode if it's slightly off. use fix symmetry to fix it up on the other side.

lanosrep1
03-26-2008, 02:00 AM
Overall .. looks good :)

Poly density in the shoulder and chest region looks ok.. could be a little lower.. ala Tarons modeling Tutorial.. but not excessive IMHO.. good form :).. looks a little heavy in the back and lower body.. not sure if you have started working on that part yet.. testing the rig.

I'm really trying to learn from the master..(Taron :)) to keep the polys as low as possible and use displacement maps.. its not easy to keep a balance between density and flow.. it's a tough one.. still learning myself.. but it pays dividends when you start to rig and animate :)

good luck.. keep up the good work! :)

My 2cnts.. which as of now is worth 1 cnt in the world economy.. :)

G.

Ulven
03-26-2008, 08:54 AM
PLease bear with me... I know I can be dense... but trying to make sure I understand not only what you are saying... but why...

1. I unparent the children of the clavicle -- which is a bunch of nulls and the upper and lower arm, hand, etc.
2. Parent those bones to something (anything) else, but make sure they keep all of their other settings (besides their parent).
3. Move the Clavicle to a better position
4. Add a hold bone that runs up and down... basically perpendicular to the clavicle (or maybe a slight angle inwards)
5. Parent this to the spine -- OK, WHICH spine? The Null Spine_PVT? Or does it matter?
6. Move the other bones back to parented to the clavicle.

So... that whole moving bones to a new parent was just so I didn't have to tweak all of the other bones one by one after moving the clavicle (because their position is basically all right?) Or is there some other subtle purpose for that?

Also... (you Brits!) I am assuming that eggs = X, why = Y and zed = Z?

1. You unparent the direct children (first child position only, not the whole hirearchy below that) This is just so you can adjust the base and orientattion of the clavicle freely without having anything go with it.

2. Yeah, you can make a temporary null or just parent it to a spine bone.

3. Right on

4. Just add a hold bone going from near the top of the spine bone (or in fact, a bit below), pointing towards the clavicle.

5. All your bases are belong to the top spine bone.

6. Yeah, parent the rest of the arm back in place when you're done.

Your assumptions are correct with regards to the eggs etc (although I'm not a brit, I'm Norwegian)

MarkInTx
03-26-2008, 10:57 AM
Ulven - Thanks... sorry for calling you a Brit.

Lanosrep - I hear you... I went through Taron's DVD and made a head that had about 500 faces instead of the one I am using now that clocks in at almost three times that. (In fact the icon I use on my signature right now is what I created from Taron's DVD). My problem is that my model had a generic look, and I found myself wanting to tweak it to look like something more specific -- and there were just not enough polys to do that -- which I know is the point. He wants a good form and the other work is done in zBrush. The problem is that I don't know zBrush and so I am insecure about what I can eventually do there -- so I tried for a middle ground with the mesh.

Of course, I may find out that all of those polys bite me in the butt now... but I hope not!



I'm really trying to learn from the master..(Taron :)) to keep the polys as low as possible and use displacement maps.. its not easy to keep a balance between density and flow.. it's a tough one.. still learning myself.. but it pays dividends when you start to rig and animate :)

StOuen
03-26-2008, 12:35 PM
I am often putting in hold bones in the chest / upper body area but usually parent to the nearest part of the spine. Works fine but is this best practice?

MarkInTx
03-26-2008, 05:45 PM
OK... I think I got that...

So... how crazy should I go with adding hold bones? The area above her breast now holds OK... but not under her arm... and there should be a bone at her shoulder blade... should I add one there?

How Many bones is too many I guess is another way of asking it.

(And I get this feeling that the answer will be: "Well it depends" But if you can give me some guidelines, that would help...)

Assume that she will be naked from waist up (probably not... but) and I want semi-realism... how many bones is too many?

http://digitalartistguild.com/Tests/Messiah/MS3_SS4.jpg

kursad_pileksuz
03-26-2008, 06:33 PM
You may want to start using weight tools with your bones to decrease number of bones needed. There is not rule of too many bones. It all depends on your scene. But using weight tools may improve rigging. Also weights are dynamically updated inside setup so they are easier to adjust

Suricate
03-26-2008, 07:51 PM
Mark, maybe you should check out Joe Cosman's CDs on rigging. For bipeds, Joe usually suggests having a muscle bone going down from the tip of the shoulder bone to the spine, this gives already a nice deformation for that area.

In general, Joe's CDs give you a lot of insight into messiah, especially in the area of deformations. I am just going through his facial rigging CDs and some stuff I found really mind-opening (and I don't consider myself a technical noob :) ).

peksi
03-26-2008, 09:16 PM
Wellity well, the deformation sure is ugly on last image, buuut, have you tried that pose with your own body? It is quite impossible to rotate arm higher than t-pose just by rotating shoulder bone. Not to mention that you actually rotated clavicle down and shoulder up so that arm is higher than in t-pose. Try doing it for yourself, painful and not even close :)

edit add:
Also I think that your clavicles root are still too high, study how your body behaves when you lift your arm higher than in t-pose, try to locate point around it rotates.

Bugpoo
03-26-2008, 09:17 PM
Well, it depends....just kidding. I usually animate characters hitting extremes when rigging them. I can see what breaks, needs hold bones, needs model adjustments very quickly. Not the only way to troubleshoot it, but it works for me.

Also, Suricate is very right about Joe C's instructional CDs being very helpful :-)

Peace...

OK... I think I got that...

So... how crazy should I go with adding hold bones? The area above her breast now holds OK... but not under her arm... and there should be a bone at her shoulder blade... should I add one there?

How Many bones is too many I guess is another way of asking it.

(And I get this feeling that the answer will be: "Well it depends" But if you can give me some guidelines, that would help...)

Assume that she will be naked from waist up (probably not... but) and I want semi-realism... how many bones is too many?

MarkInTx
03-26-2008, 11:48 PM
kursad_pileksuz: You may want to start using weight tools with your bones to decrease number of bones needed. There is not rule of too many bones. It all depends on your scene. But using weight tools may improve rigging. Also weights are dynamically updated inside setup so they are easier to adjust

OK... That's an interesting idea... I will play with that a bit -- though my experience with XSI and weights makes me dread the thought!

In general, though, would you say that there is a rule of thumb that says: The denser your mesh (more polys) the more bones you will need to keep the deformations smooth?

Suricate:Mark, maybe you should check out Joe Cosman's CDs on rigging.

In general, Joe's CDs give you a lot of insight into messiah, especially in the area of deformations.

Bugpoo:Also, Suricate is very right about Joe C's instructional CDs being very helpful :-)


Wow... 2 thumbs up for Joe's videos, eh? Well the thing is, I have both Rigging1 and Rigging2. Bought them a year ago when I was playing with Messiah last. And -- unless there is a new tutorial out that I haven't seen -- I didn't find them nearly as helpful as you suggest. Maybe it's just me... but to tell you the truth, I don't remember Joe's videos being very much on the theory of why to do something. I remember a lot of HOW: "Click this, extend this, pitch this there. OK, that looks good, doesn't it?"

Rigging 2 was even faster -- it was like he had to catch a plane or something. Wow, I never hit pause so much on a video before in my life! (Well, Maybe Taron's ;-)

But, anyway, I don't remember much explanation about why something was done.

Actually, I was hoping that by buying Auto_rigger, I was going to jump past needing the Tutorials... sigh! No such thing as a free lunch I suppose.

In fairness, it has been over a year since I watched them. Maybe they'll speak to me more now...

Well, it depends....


Hehehe... yeah, I probably have that coming ;-)

Bugpoo: I usually animate characters hitting extremes when rigging them. I can see what breaks, needs hold bones, needs model adjustments very quickly.[/QUOTE]

Interesting idea... thanks...

kursad_pileksuz
03-27-2008, 12:54 AM
"In general, though, would you say that there is a rule of thumb that says: The denser your mesh (more polys) the more bones you will need to keep the deformations smooth? "

Actually more bones can make the your mesh look less organic, it depends on your polygon layout and how you lay your bones. Based on my own experience I would recommend keeping number of bones lower and using more weights. But again Messiah`s bones are well enough that you can use as many as you want.

I personally think that Joe`s cds are tremendous help if you want to rig and understand messiah more. He covers weights in Messiah in depth. I think that watching those tutorials again may give you more ideas this time. I also found that his facial tutorals explain alot about weighting process inside Messiah. You would be surprised how creative Messiah is and Joe himself when it comes to weights.

MarkInTx
03-27-2008, 01:21 AM
I personally think that Joe`s cds are tremendous help if you want to rig and understand messiah more. He covers weights in Messiah in depth.


Well, that certainly seems to be the consensus... so I will sit down and do that...

I also found that his facial tutorals explain alot about weighting process inside Messiah. You would be surprised how creative Messiah is and Joe himself when it comes to weights.

I don't have the facial rigging tuts yet. I probably will buy them... but I want to get the body working first.

Thanks for the input.

Julez4001
04-20-2008, 05:49 AM
Hmmmmmmm
After I place the rig into the position I want, when I click on AutoRig, the rig itself seem to jump higher. It is really evident on the hands and arms. Doing anything wrong?

---------------------------

Update

Okay I figured it out. Its because I scaled and move (down on the Y) the Character_Root null.

What am I suppose to use to scale the rig?

Ulven
04-20-2008, 10:05 AM
Scale the rig using bone lengths only. The scale popping it out of place is happening because the script is using the bone length parameters to place additional bones and nulls etc in your character, creating the "under the hood and out of sight" stuff. I'm afraid that's a limitation that has to be worked with.

Julez4001
05-17-2008, 01:01 AM
Any advancement on solving the "scale" limitation?

Ulven
05-17-2008, 12:41 PM
Sorry mate, I've not had a chance to fix that yet (too busy), although I have an idea how to do it. Once I have some spare time, I will fix this and some other things I've been planning on changing.

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