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Salem78
05-27-2005, 12:02 PM
I'm a little bit newbie to rigging characters and are following this tutorial http://www.puffandlarkin.com/lightwave/tutorials/character_rigging/skelegons.html. I'm now working on "Weight maps", but I'm not sure about how divide up some weight maps on my model.
I'm not sure about bones "Spline03", "Splin04" and "Collarbone", how to divide the upperbody on those bones. My guess is like the picture, but I dont know:

http://web.telia.com/~u27807121/images/Weigtmaps.jpg

What do you say?


And what about "UpperLegBuffer"? If I put upperleg for bone "Upperleg", what part of the body do I put on "UpperLegBuffer" then?

And last, what about the butt? What bones should the butt belong to? The "Pelvis"-bone or "Upperleg"-bone? Or both? Another?

Do you know if there are any site about how to more exactly divide a body into weight maps? I found one, but that model didn't show that much I needed to know and didn't have bones like "splines" and "Upperlegbuffer".

rwhunt99
05-27-2005, 02:19 PM
Well Salem; If you are just getting started, I heartliy suggest you try Jonny Gorden's books "Cartoon Character Creation,it is a two book set that will take you from newbie building a character all the way through to rigging and weighting the character and how to efficiently animate them. It's very good because it doesn't give just bits and pieces on the whole process, it's the real deal on how the pros do it. I can also reccomend Tim albees book on Character animation, they are two different styles that will allow you to learn everything you want to know and will drastically cut your time of frustration to a minimum. Both books are published by Wordware, probably the best place to find references books on Lightwave !! :D

Surrealist.
05-27-2005, 02:58 PM
I'll second the plug For Timothy Albee.

This is the basic technique. First you should create the maps with the Bone Weight tool, set to clip and threshold to 0. This automatically creates all of the maps with the same names as the bones with 0 as the value.

Having the maps the same name will automatically assign them to the bones in Layout.

The thing to do is think logically about how your own musles move the skin and when creating the maps evenly distribute the wieghts to overlap.

As a simple example take the knee, thigh and calf.

The Knee joint points would have the value of 50% Thigh and 50% Calf

The next ring of points moving up the leg would have a value of 75% thigh and 25 % calf and the next maybe 100% thigh and then so on.

You do this - not in vertex paint! Do this right in modeler by selecting the points and using Maps/Set Map Value.

You can set any combination of values 90/10 , 85/15 etc and you can give points that share three bones values such as 50/25/25 as an example in areas such as the crotch where you have a center bone and two leg bones that meet.

The thing to keep in mind is that any one point should not add up to more than 100% and not be less or the point will either jumpo ahead ore get left behind in Layout when you move the bone.

Just think of howw the bones will stretch things around.

To keep track of things, use the point statisitcs window after selecting points to see by the bone weight how things are adding up if you have lost track.

One more important setting is "Use Weightmaps only" in Modeler.

Now this is very brief and sorry for that but I would strongly sugggest Albee's book. There are many schools of thought on this but this guy has over ten years of rigging and a traditional animation background from working at many places such as Disney where he studied under one of the great masters of animation.

Also his rig set up is pretty simple and easy to use as well as practical and again based on years of research and it shows.

There is so much more to the technique I gave you a glimpse of, it really would be a good idea to check it out rather than struggle though less than workable methods.

t4d
05-27-2005, 10:19 PM
A weight maps for each Bone !!!!!! :confused:

Tim's a god
But That's Way too work much there, AND too much fine tuning is needed

And your trying to use Maya workflow in Lightwave :eek:
You should uses Lightwave for what Lightwave is good for
That weight map per bone idea is WAY overkill when LW has much better options

I use XSI as well and even there you don't go to that level very often and XSi has better Joint and weight editing tools

OK in LW start simple then add weight maps as needed


my base for weight maps are


1 weight map per leg ( sometimes add 1 for each foot if the heel needs help )
1 Weight map covering Hips upper body & Arms
1 weight map per hand ( sometimes Add 1 Weight map per Finger )
Neck and head in there own weight maps
and a weight map for each eye

Then i Blur ALL weight Maps

THAT"S IT !!!
Going down the complex weight for each bones
straight away is a huge WASTE of TIME !!!
and will cause more errors then no weights at all (try it with No weight you'll see )

Start with big ones then as you see errors
Don't run to weight map straight away

Check your bone strength, joint options
AND check the Bone strength of bones in the area,
play with you bone fall off

after you play with these settings
you better understand Where and how a new weight maps needs to fix any problem you have

Oh Jonny Gordens Book does Rock :D

and He has the same basic way to work with weight maps
( keep em Large with many bones using the same weight maps)

Surrealist.
05-27-2005, 10:37 PM
Thanks for the input. I know there are many schools of thought here. Just trying to help the guy along is all.

t4d
05-27-2005, 10:52 PM
Surrealist.

I really didn't mean it to read like I was attacking Your method ( but it did sorry :o )

And your totally right

they are many ways to do it and everyway works for the artist that's using it.

i just get afew email from newbies and this road seem to be the first one that all go down

So was just trying to put up a bigger Road sign that there's a more " Lightwave " way of doing it :D

Salem78
05-27-2005, 11:57 PM
I'll second the plug For Timothy Albee.
First you should create the maps with the Bone Weight tool, set to clip and threshold to 0. This automatically creates all of the maps with the same names as the bones with 0 as the value.

As T4d says: Weight maps for each bone? What's your opinion about that?
If it's waste of time, no idea to continue the tutorial I'm using then? It tells I have to make Weight maps for each bone except "Hand" and "Foot" and "IK_Leg_Plane" is using same weight map as "HipBuffer":

http://www.puffandlarkin.com/lightwave/tutorials/character_rigging/i/Tree.jpg


I'll second the plug For Timothy Albee.
One more important setting is "Use Weightmaps only" in Modeler.

Where can I found "Use Weightmaps only"?



Both books are published by Wordware, probably the best place to find references books on Lightwave !!

Books is the key to the perfect world:)
My biggest problem is that I hate reading books...I know.....very stupid to try 3D-modelling then:)

t4d
05-28-2005, 12:26 AM
check out this rig

simple and as afew Weight maps as needed and it works well

http://www.thomas4d.com/Mrgrey_T4DV3.zip


http://www.thomas4d.com/mrG_Pic.jpg

Salem78
05-28-2005, 12:58 AM
I have checked that rig now, it's looks ok.
I took a look in weight maps-list and noticed there was "Hand" and "Left_hand", but no "Right_Hand"?. They were on both hands, the difference was that "Left_hand" included the fingers. There are "Fingers" for fingers, so why include all fingers with the hand?
And what's the point with "Left_Hand" for both hands, instead of a "Left_Hand" for left hand and a "Right_hand" for right hand, ?

Surrealist.
05-28-2005, 01:42 AM
My opinion is that you have to find something that works for you.

It might not be a bad idea to just assign weights as described by td4 and check it out. Maybe it will simplify things. I don't know.

Keep in mind though that this is a different technique. I was only trying to get you up and going with what you had started.

Just keep in mind that rigging is complex and mixing techniques at this stage will only complicate. You have to know all of the options and how they interact.

My advice for now is keep it simple. Do one or the other.

As to the Wightmaps Only option that is in Layout in the bone properties panel, but it would only apply with the technique of a map for every bone.

And as to books I know what you mean but Albee's reads mostly like a tutorial


Surrealist.

I really didn't mean it to read like I was attacking Your method ( but it did sorry )

And your totally right

they are many ways to do it and everyway works for the artist that's using it.

i just get afew email from newbies and this road seem to be the first one that all go down

So was just trying to put up a bigger Road sign that there's a more " Lightwave " way of doing it

Cool understood, td4. No matter how you skin the cat it still screams like mad! :D

t4d
05-28-2005, 02:03 AM
I have checked that rig now, it's looks ok.

I took a look in weight maps-list and noticed there was "Hand" and "Left_hand", but no "Right_Hand"?. They were on both hands, the difference was that "Left_hand" included the fingers. There are "Fingers" for fingers, so why include all fingers with the hand?
And what's the point with "Left_Hand" for both hands, instead of a "Left_Hand" for left hand and a "Right_hand" for right hand, ?


this model has been rigged with 3 different versions of my rigging tools
SO there are old V2, V2.5 & V3 weight maps on the model ( sorry about that )

But it shows the different ways I have done it

Now on that V3 rig " Hand " has both Left and right hands in the one weight map
You don't need a Left and right ( like you do with legs ) due to the hands are so far away from each other at frame 0, So the L/R hand bones will not effect each other. (this idea also carriers over to the arms , you see there's no left and right arms as well it just "arms" )

for fingers there alot of bone strength with so many finer bones that may effect the hand

SO I give the fingers they own weight map

NOW if i find the first finger's bones are effecting finger 2 mesh ( if I modeled them too closes together in Modeler ) I'll create weight for each finger 1,2,3,4, ( 0 for thumb ) the finger are the only place i really break up the weight maps like this.

But I see no reason to create a weight map for each finger joint that would be overkill.

Other way to see what I'm doing

load it up in modeler and see how large the weight maps and what they cover

next layout just load up the model and convert skelegon to get better Idea of what i mean. you may have some minor map assignments to do
but these not much And it's alot quicker to tidy up in layout then spend all day creating & editing a weight maps for every bone in Modeler

BUT MY main dislike for the Weight map for every bone method IS
when you do need to tidy up something Your in A HUGE WORLD OF PAIN !!!!!! :mad:
you edit the bone settings in Layout but need to edit the weight maps in modeler
? Not fun if you got a ticky rigging job in front of you...

Dodgy
05-28-2005, 10:02 AM
My two cents:

Don't use weightmaps.... Instead lay your mesh out spreadeagled and add hold bones. I very very rarely use weight maps, instead prefering to add bones to hold the shape of my objects. Then you don't have to maintain the weight maps as you build.

If you have to, use one for each leg, one for the torso and arms/hands, and maybe one for the head if you don't include that in the torso map. Very economical.

If you're doing a game, use a weightmap for each bone. This is the only time you need this level, as game engines prefer it.

Salem78
05-28-2005, 11:08 AM
Don't use weightmaps.... Instead lay your mesh out spreadeagled and add hold bones. I very very rarely use weight maps, instead prefering to add bones to hold the shape of my objects.

If you're doing a game, use a weightmap for each bone. This is the only time you need this level, as game engines prefer it.
Don't use weightmaps?? Lay my mesh out spreadeagled and add hold bones? Never heard about that, can you explain how to do it?

I'm not doing a game...yet:)
I just wanna make some illustrations with human bodies in different posings and environments. And later, if I finally can handle the rigging of characters, try to make a short animated fighting clip would be fun. But I wanna do it with realistic highpolys characters and want every move and motions to look good.

SplineGod
05-28-2005, 01:25 PM
I never use a weight for for every bone and typically nothing even close to that complicated. Typically you might do that for game engines but its rarely if ever neded on anything else. If you model your character so that you you can avoid some cross influence between bones it will help out by reducing the need to isolate vertices from particular bones.
I usually keep the legs and fingers spread apart and then bring them back into a more natural pose after rigging. Lightwave bones are deformers and work as soon as you REST them. It makes sense to test your deformations first before deciding how to fine tune those deformations. Its easier to add hold bones in layout in most cases as opposed to going back to modeler to fiddle with weight maps. Hold bones can also be animated to help assist with deformations such as muscle effects or just simply to keep areas from collapsing.
Worst case will be that even if you need weight maps they will be much simpler ones. For example, both arms can belong to a single weight map. All the bones in both arms can be assigned to a single weight map. Much of the time people use weight maps for the wrong reasons.
I would take the time to study the settings in the bones properties panel and do some experiments since there are a number of tools associated with bones that effect deformations.
Weight maps have their use but I found that they are better used as a tool of last resort rather then first. :)

Salem78
05-29-2005, 01:02 AM
Ok, I will try "hold bones", but can't find out how to add hold bones in Layout?

SplineGod
05-29-2005, 01:07 AM
Hold bones are just regular bones used to keep areas from moving. An example would be to add a couple of ribs to keep the arm pit from collapsing when the arms are lowered to the sides. Another example would be to use a hold bone in the face of a character if you see it being affected slightly by the movement of other bones.
I usually just use the draw bones tool to add them (on frame 0) and then hit the r key to rest and activate them.

Salem78
05-29-2005, 01:22 AM
Ah, ok! I got it now.
Tried move around some hold bones and it seems to work great. Let's keep on with this!
Thanks!

Edit:
Just a question:
Can it cause any problem if using too many hold bones?

SplineGod
05-29-2005, 01:55 AM
Too may could hurt but then maybe not. It depends on the density of your mesh and how many bones you have as well as weight maps, expressions and so on.
As I said before, LW bones are deformers. Each bone is surrounded by a capsule shaped force field. Every bone effects every vertex in the mesh. The falloff determines how fast the effect a bone has on a vertex falls off based on distance. Also the bone strength, multiply by rest length and so on also influence this.
The bones size when you rest (rest length), its postion (rest position) and orientation (rest rotation) are all taken into account when Layout internally determines which bones have how much influence of each vertex. If you have a lot of vertices and a lot of bones it can start to cause slow updates. If you
When youre rigging I typically split the it into two parts:
1. Rigging for deformations
2. Rigging for animating

I try not to mix the two. When you you rig for animation you want a rig that is stable, poseable and provides fast feedback. WHen you mix in the deformation aspect is just slows down. Theres a lot of ways around this but you kind of have to determine when to use a lot of hold bones vs using weight maps. Since I tend to also use my hold bones to animate with as well to effect deformations weight maps may not be as useful since you cant really select and move vertices based on them in layout.

Salem78
05-31-2005, 11:18 AM
T4d:
I'm checking around "MRGray"-rig and see the bones have different colors, why?
Example "hold bones" are black, do you do anything specially that makes them black, or do you just color them black to know which bones that are "hold bones"?
And what about the other colors?

SplineGod
05-31-2005, 11:32 AM
Coloring bones is a way to let an animator know which bones do what. You can also use colors to show which is the right and left side of a character and so forth - basically anything to make selecting the proper bones easier. Using good naming conventions also helps alot. You can also place things like ***, or @@@ in front of bone names to help find them out of a long list :)

Salem78
05-31-2005, 11:41 AM
Ah, ok!
About naming bones, how to rename "draw bones"?
When choosing "Bones" or "Child Bones" a window popup where you can fill in a name before drawing it out, but not on "draw bone".
Looked in "Scene editor" to find anything but nope.

SplineGod
05-31-2005, 11:57 AM
It would be more tedious for me to have to name bones as I drew them.
I usually use the rename hierarchy command in the setup tab to rename bones after Ive created them. You can also rename bones when you mirror or clone them so you could rename a bunch of bones that start with the word Left to the word Right. :)

Surrealist.
05-31-2005, 01:16 PM
You can also rename a bone in the schematic view by right clicking on it.

In Modeler use "rename bone" in the set up tab after you select it (polygon select mode)

Dodgy
05-31-2005, 03:02 PM
If you have many bones to rename, you might want to look at this:

http://vbulletin.newtek.com/showpost.php?p=255401&postcount=58

t4d
05-31-2005, 09:46 PM
T4d:
I'm checking around "MRGray"-rig and see the bones have different colors, why?
Example "hold bones" are black, do you do anything specially that makes them black, or do you just color them black to know which bones that are "hold bones"?
And what about the other colors?


yeah as SplineGod say's it's all for the character animator's workflow
all the colours are setup by the plugin ;)

Naming is a way to help with workflow for Animators too afew quick clicks in the filter in Dopesheet go along way to making a selections and working with the dopesheet.

jeanphi
06-01-2005, 07:04 AM
Just a little info about my rig.

Read ALL the tutorial first. It's about a way to seting up IK in LightWave with a premade character provide in the tutorial, not a weighting tutorial.

Basicly it was a character rig for a game engine we used in 2001. At this time I needed one weight map per bone that deform the skin for exportation. I recomend you to read the thread at spinquad (follow the link on the tutorial).
This is not a beginer tutorial (sorry) as many things are not step by step presented.
If you need some more explanations about weights for this kind of rig, send me a private mail.

I planed to add a weight tutorial with vertex paint but for now I don't have time.

jeanphi
06-01-2005, 08:03 AM
here is the link as it looks broken from the tutorial.

http://spinquad.com/forums/showthread.php?t=1555

Salem78
06-04-2005, 10:27 AM
Me again:
I think I have read about this earlier, but can't find it: When clicking "Match Goal Orientation", the hand-bones turn 90 degress, why? Is that ok or have I done something wrong?

SplineGod
06-04-2005, 12:09 PM
Thats pretty normal since the orientation of the hand is different then the orientation of the goal. After turning on match goal, rotate the goal so that the hand is properly oriented.