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rebelliousthoughts
12-29-2008, 03:04 PM
Hi guys,
im Doing animation for the first time and the rigging i done isn't good.
so im having problem during animation .
and when ever anything goes wrong i try to go into envelope and adjust the weight of that bone.
Special im having problem with fingers.
is it ok to fix weight during animation ...?

Dichotomy
12-29-2008, 03:09 PM
The risk you run with that, is that when you fix the weights in one spot of the animation, it may make it look bad in another; or if you have blend shapes set up to work with that weighting, changing the weights will make the blends not fit exactly where you had them.
As far as your objects hierarchy and history, im pretty sure you aren't going to hurt your setup.

rebelliousthoughts
12-29-2008, 03:59 PM
then whts the best way to fix that problem afterward? because in new to animation and im doing this project for my final thesis project. of graphic design programe

tonytouch
12-29-2008, 05:26 PM
hi ,

once you have painted your weights - these should be deforming your geometry in a smooth way ( at least , that is the way it should be ) - never change the weights during animation !!!

( you can use corrective shapes later to correct skinning deformation , but before that , your weights must be accurate ! - also , i think , this is quite advanced technique ... so maybe it is best , you dont take care about "corrective shapes" - at least , it might make everything too complicated for someone who is new to animation )

- when it comes to weighting, the best is , to step through all individual bones ( e.g. first the SPINE , then arms , then legs ) one joint after another - painting edge-LOOPS of 1.0 as weight .

- in the next step "skinning" , I always set on the surrounding LOOPS a value of 0.3 ( to create a falloff ) . usually this ends up in a very stable skinning . ( this might take quite some time , especially if you are a beginner )

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you can also build a "simpler" lowres-geometry around your character ( if it is a highres-character the BEST WAY ) - you bind then the lowres-geometry to the joints and paint the weights ( simple and easy way ) - finally you copy your skinweights from the lowres to the highres-version .
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some people like to "smooth" their weights , with the smooth-button . but that often "messes up" the weights . i personally don't use "smooth" ( might be , this is the failure you did , while skinning - you might have used the "smooth" to often !!! you will never gonna correct it properly , so it might be the only way , to completely re-do the skinning . ( but i cant tell that , without a screenshot or withuot looking at the rig )

anyways...

for the fingers :
- be sure your geometry is symmetrical , so you can later mirror your weights from one side to the other ( this can be really a pain-in-the ... if you skin your character , and finally realize , it is not mirrored 100% correctly ) - i always use "abSymMesh.mel" ( from highend3d.com ) to check about the geometry before starting any skinning

- stepping through all fingers of one hand , takes some time ! so don't loose your patience ! finger-by finger ( first 1.0weights , then 0.3 and 0.1 to achieve a soft-deformation ) - and if you are out for "gollum-like-perfect-hands and fingers" ... be aware , that these people used hundreds of blendshapes just for gollums hands . so most important is a proper "joint-placement" , "joint-orientation" - and clean skinning

for the mesh in general :
- most uncomplicated are "symmetrical" meshes ( but in some cases you want them to be asymetrical - but i recommend an symmetric-mesh )

- is the mesh "CLEAN FOR RIGGING" ? are all vertecies merged ? is the history of the mesh deleted ? are the face-normals in the direction , you want them to be ?

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maybe you want to post a screenshot of your character-rig . good luck ;)

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