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omega-0nd
10-21-2003, 04:58 PM
i mean...for example i have 88 bones, is correct to create 88 weight maps for every bone?

Tudor
10-21-2003, 05:03 PM
No. Several bones can use the same weightmap.
I usually use these for a character.

body, right leg, left leg, right foot, left foot, right arm, left arm, right hand, left hand, figers and head.

11 weightmaps.

telamon
10-21-2003, 06:29 PM
Tudor, as far as I know, you are a professional animator. I can see in your list that you do not recommend to make any waist and hips weight map. Is it a tip?
To be honest, I have always wondered why all tutorials I have read recommend to build these Wmaps.

Thanks for the tip.

I will follow your recommendations in my quest for reducing the amount of maps in my models (too many endomorphs, weight maps and UVs at the moment, my models become heavier and heavier).

Tudor
10-21-2003, 06:41 PM
I'd say don't do any more work then nessecary. If a separate weight map adds to the character, then have a separate weightmap. If the effects is hardly noticable, don't waste your time on it. An even easier way then weightmaps is to add extra holder bones. Bones there just to hold geometry in place.
About all tutorials.. Ppl have different ways of doing stuff. If you come from another package then LW you have probably never even heard of many bones per weightmap. Even if you are a LW user you might use this way as when painting weights using skelegons in modeler with vertex paint it uses the same way of one weightmap per bone.

telamon
10-21-2003, 06:55 PM
My usual weight map architecture used to be
Arm - Forearm - Hand (left and right are separated)
Thigh - Shin - Foot - Toe (left and right are separated)
Head - Neck - Body - Waist - Hip.

Moreover, I used to complement the model with endomorphs at the joints for better bendings...

But I just realised (by reading you) that the multiplication of weight maps does not make sense on the arms and legs and also on the body....

Nevertheless, I will not add holder bones because I animate my characters my Motion Builder and this package does not include holder bones in the "standard" rig structure :surprised

Thanks

adrencg
10-21-2003, 07:50 PM
Originally posted by omega^0nd
i mean...for example i have 88 bones, is correct to create 88 weight maps for every bone?

I've posted this before, but here I go again...

This setup is simple and works nicely:

Right leg, Left leg, Right arm, Left arm, head(very high strength), right eye, left eye.

No torso weights. Every weight map bleeds out into non-weighted space(except eyeballs, of course). This setup keeps weight maps from crisscrossing, which is usually where problems arise with getting nice bends. It's not necessary to weight each finger individually, just spread them out wide in modeler.

Get FI's weightmapBlur plugin and apply over and over to each map until they spread nicely into the "non-weighted" torso area.

Mike

SplineGod
10-21-2003, 10:02 PM
There is absolutely no reason to use a weight map per bone unless its something a game engine needs.
Most of the stuff I do doesnt use any weight maps. As Tudor pointed out you can have multiple bones effect only certain weight maps. It makes more sense to me to test deformations FIRST then decide where a weight map might be needed. I only do this after an extra hold bone or two doesnt seem to do the trick. Do things in a logical fashion. As a general rule; Bones, first, check deformations, try hold bones and THEN go with weight maps.

projectcoil
10-21-2003, 11:24 PM
I don't wish to hijack this thread, but I got to ask. What does Maya have that Lightwave doesn't have in the animation area? When I look at Stahlberg (http://www.androidblues.com/)'s characters. Their deformations are incredibly precise. Is it possible to get that kind of accuracy with Lightwave. Have the thigh crease with the hip and such? Or does it just require a huge amount of tweaking.

http://projectcoil.dyndns.org/stool.jpg

telamon
10-21-2003, 11:28 PM
He may have tweaked his geometry after bone deformation to get the best flow of polys... It is a still image, you can do whatever you want to get the best from your mesh ;)

Mike RB
10-21-2003, 11:29 PM
are you sure she wasent modeled in that pose? (not saying she was but It's very possible)

Mike

projectcoil
10-21-2003, 11:33 PM
He has animations in his gallery here (http://www.optidigit.com/Galleries/longform/long-main.htm) It shows the deformations (creases) correctly even in animation.

telamon
10-21-2003, 11:34 PM
I think everything shown here can be done in LW with a good rig and endomorphs even without weightmaps ;)

kretin
10-22-2003, 01:36 AM
I don't wish to hijack this thread, but I got to ask. What does Maya have that Lightwave doesn't have in the animation area?
Lots :p

Maya has many more deformation options than LW. Stahlberg uses cage deformation for his joints which is a feature that LW doesn't have, although you can approximate it using a low-res subD mesh with Smartskin.

But to bring us back on track I agree with Tudor, the less weights the better. Weights are definitely your friend, but you should only use different weights for an area if you have to, and never even close to 1 weight per bone (that evil "Bone Weights" tool in Modeler should never be used for characters)

SplineGod
10-22-2003, 02:32 AM
Originally posted by projectcoil
I don't wish to hijack this thread, but I got to ask. What does Maya have that Lightwave doesn't have in the animation area? When I look at Stahlberg (http://www.androidblues.com/)'s characters. Their deformations are incredibly precise. Is it possible to get that kind of accuracy with Lightwave. Have the thigh crease with the hip and such? Or does it just require a huge amount of tweaking.

The more accurate something has to look you better believe the more tweaking it takes. Read some of the cinefex articles on how much work went into individual characters on many of the CGI characters you see in movies.
I think when it comes down to it to get things to deform precisely the way you want it can be done with a combination of endomorphs driven by cycler rather then simple expressions or channel follower. Cycler allows you to take a complex curve that represents an endomorph and use something like a bones pitch channel to control it. You can determine exactly at which angle of the controlling channel when something morphs to a certain percentage of its full range. You can stack endomorphs and easily determine how then mix at certain angles of the controller and by how much.
On top of this you need point level control in layout to precisely place points. This can be done using XTools, a $60.00 layout plugin or with some of the new tools in LW8 that were demoed at Siggraph. Again, with Xtools, the points show up in the graph editor which means you can have points move to specfic positions based on the range of a controller such as the pitch of a bone as I mentioned.
The same methods I just described can be used to sculpt muscle shapes, wrinkles and so on based on what other things are doing.
I think a lot more can be done with the current LW then most people realize and with LW8 that will even be much more true. :)

There is no magic bullet other then massive amounts of tweaking and the tools to allow it. Lightwave DOES have those tools available.

telamon
10-22-2003, 10:39 AM
I agree with Larry. In such a stuff there is 90 % of things done by the animator and 10 % done by the software package. Afterwards the package is more or less flexible and simple to use. Nevertheless a good animator on blender or any other basic package can do much better than a poor animator (like me) on a high end package like Maya however powerful and simple it may be.

Not an attempt to hi-jack this thread as well, just for one question... is it possible to model a low-res box character to use it as a deformation cage for a very detailed with not exactly the same shape as the original deformed object ?

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