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Dudeman
01-04-2005, 06:01 PM
Hi,
I have a character that has been smooth bound and created blend shapes so it deformed properly .

Although at the hip area I have seem to have cornered myself. I only have one joint for each the left and right hips. I created 3 blend shapes, one for each axis. But when the leg is posed sharing 2 or 3 axis I get bad deformations(I bet you saw that coming). Unfortunately those were the last blend shape I created.

For shoulder area I had 2 joints, the upper/top joint with 2 blend targets for 2 axis' and then a joint part way down the upper arm and had one blend target for its twist/3rd axis. This worked well after figuring out how to control it.

Besides how I made the shoulder work does anyone have a solution to what I backed myself into?

I'm thinking of backing up and trying the same thing I did with shoulder but this is a last resort because it may work as well.

Thanks,

-Dudeman:thumbsup:

pollywoggles
01-08-2005, 02:33 AM
... so, to get it straight, the blendshapes look good until you rotate past a certain point, then they start getting ugly because of the additive nature of blendshapes... right?

How about righting an expression that clamps the change in the blendshape between two values, so it doesn't go over -- or use, say, a conditional to ensure the blendshapes don't turn sour.

Dudeman
01-08-2005, 04:50 AM
Basically the problem is that 2 or 3 blendshapes (1 for each axis) being used for a certain pose that incorperates 2 or all three axises are additive to each other. So while the blendshapes look good on their single axis it looks really bad when the axis is shared.

I'm not very technical so I thought I would try have the hip only rotate on 2 axises and add a joint (if I can without breaking anything) down towards the thigh and have it rotate the twist axis. So I will only suffer the blending of 2 blendshapes in stead of 3. And live with it.
I did the soulder this way and it works perfect after I figured out how to control it.

Understand?

I'm very hands on with this stuff so creative expressions are a bit beyond me.

-Dudeman:thumbsup:

pollywoggles
01-08-2005, 10:20 AM
Yeah. Without doing expressions I can't see you working around this... but, here's a link to Michael Comet's poseDeformer. It's a free plug-in that sounds like it will do what you're looking for:

http://www.comet-cartoons.com/toons/melscript.cfm

... and a good article and tutorial about that solution can be found here:

http://www.tokeru.com/twiki/bin/view/Main/MayaRigging

Good luck!

anthonymcgrath
01-11-2005, 02:19 PM
hey that posedeformer is a fantastic plugin!! unfortunately I'm only on maya v5 doh!!
is there anything like that for maya 5 (on highend3d possibly?) or am I scuppered!!

ant
newcastle
uk

anthonymcgrath
01-11-2005, 03:31 PM
okay, had a bit of a dig on highend3d.com. found this:

BSpiritCorrectiveShape v1.0 by Christian Breitling

the blurb says:

"Creates a CORRECTIVE BLEND SHAPE for your binded mesh.
very fast and reliable compensation for mesh deformation on heavy stressed locations like knees.
Modelling directly in the desired pose without disturbing local vertex movements."


has anyone used this? can they vouch for it? Does it work anything like poseDeformer?

cheers
ant
watcher of green progress bars
newcastle
uk

Arcon
01-12-2005, 07:29 AM
BSpiritCorrectiveShape v1.0 by Christian Breitling
has anyone used this? can they vouch for it? Does it work anything like poseDeformer?


using it extensively for a photo-realistic character animation now. bSpirit ROCKS and craps all over maya's method of making blendshapes. i don't know how people ever got good results with high-rez characters with maya's method.

NOTE: with bSpirit script its best to setup a basic animation of extreme poses you'll need the blendshapes at first. you model the shapes from the deformed pose. keep the keys in that animation while you're making the shapes, because the bSpirit script ONLY works between two objects at the same pose. (one being the original skin, the other the fixed up model).

anthonymcgrath
01-12-2005, 10:22 AM
So how does it work? (sorry I'm at work here and haven't had chance to play with it). Does it create a copy of the extreme pose (lets call it a shoulderLiftPose) then you tweak that new shape or does it just store the vertex position offsets? If it does the first one, where are the blendshapes stored?
Can you explain a little deeper into what it does -dont worry about it if your busy.

what about when you have more than one pose - are they applied in an additive manner? can you stick up a quick example toot possibly? (dont worry if yer busy - I'll just have a shot tonight doh!)

cheers

ant
adware ridden pony boy
newcastle
uk

Arcon
01-12-2005, 07:54 PM
So how does it work? (sorry I'm at work here and haven't had chance to play with it). Does it create a copy of the extreme pose (lets call it a shoulderLiftPose) then you tweak that new shape or does it just store the vertex position offsets?

i found it easiest simply to make a copy of my skin at a specific pose, export that skin to a new file and work on it there, that way you have a backup blend file as well. once that's tweaked to how the deformation should look, import it back, select the new shape, select the skin (which MUST be at the deformed pose, so the 2 meshes will look the same apart from the areas you've tweaked), and run bSpirit.

that's it, the script makes a new skin for you that's reset to the bind pose, except with the morph tweaks added (eg. like a bulging elbow joint if you were tweaking that). after that the blend procedure is the same as maya, you can make as many tweens as you need.

bSpirit can take a long time to calculate the new mesh on high-rez characters, as long as 20 mins for 40-50K poly characters. but modelling the exact look is so much quicker and gives better results for high-rez meshes, at least i found it impossible to control and predict all the wrinkling that the traditional method creates.

Dudeman
01-12-2005, 10:06 PM
Now we're gettin' somewhere!
Bspirit sounds really good for future blendshape I may make.

But it looks like Comet's tool is more of what I need. The problem is that I have so much set up already. Whether Comet's tool can work with what I already have or not will decide if I can use it or start over using it.

This is great! Lots of good info for me. Thanks guys!

I'll try Comet's tool out and see what it gives me.

-Dudeman:thumbsup:

anthonymcgrath
01-13-2005, 11:19 AM
i found it easiest simply to make a copy of my skin at a specific pose, export that skin to a new file and work on it there, that way you have a backup blend file as well. once that's tweaked to how the deformation should look, import it back, select the new shape, select the skin (which MUST be at the deformed pose, so the 2 meshes will look the same apart from the areas you've tweaked), and run bSpirit.

that's it, the script makes a new skin for you that's reset to the bind pose, except with the morph tweaks added (eg. like a bulging elbow joint if you were tweaking that). after that the blend procedure is the same as maya, you can make as many tweens as you need.


cheers cipher for that explanation. I'm just wondering if I could simply keep the modified copy in the same file hidden away under a group or in a display layer? dont see why not. Anyhow - gonna give it a shot tonight when I finally get home! So whats going on under the hood? Does it create a blendshape above the skinning in the inputs or something?

..maya6 sounds worth upgrading to tho simply for getting hold of poseDeformer. Hope they stick that in the v7 as it sounds rock solid!

Reaker
01-13-2005, 04:23 PM
Amazing plug-in guys and amazing tutorial! Thank you.
However question, do you think this is even better than influence objects? Or should I still use influence objects in arms, flexing muscles or just switch completley over to this method?

Arcon
01-13-2005, 07:34 PM
However question, do you think this is even better than influence objects? Or should I still use influence objects in arms, flexing muscles or just switch completley over to this method?

you mean poseDeformer or bSpirit..? i havn't checked out poseDeformer yet but just about to. influences objects are only really useful if their transform is animated. if you blendshape an influence hoping to get ultra-realistic muscle deformation, on high res characters your rig will slow to a crawl, because you have to enable components on the skinCluster.

once you have a good method for making blendshapes, i would use them for every joint fix that you possibly can 'cause they're quick, not having much overhead on the rig. they're good for some muscle groups too. i've found sculpt deformers can be pretty useful too (for some muscle effects, not joints), they are also really lightweight, 'cause you can isolate their influence to specific groups/sets of vertices.

seven6ty
01-13-2005, 08:11 PM
I'm hoping the blend shape influence objects turn out to be not so bad when you have your hi-rez rig hidden, but I'm also wondering how these stack up against wrap deformers. Hrmm. We'll see this weekend I suppose.

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