PDA

View Full Version : Problem Scaling Character With Stretchy Spine!

horsecrazy
06-20-2008, 12:53 AM
hi y'all
i've rigged a character & want it to be able to scale with everything working.
the only problem is the stretchy spine. if i delete the "stretcy" it scales fine but it won't with the stretchy spine.

if i scale 'character scale node', the spine joints scale at a faster rate than everything else

i used the script jsScaleJointsByCurve.mel to scale the spinejoints

what & how do i connect my 'character scale node' to so that the spine would scale less when the 'character scale node' is scaled up & vice versa?

thanks in advance.
shinyprem
06-20-2008, 08:33 AM
Hi..
Try Pulling out the IkSpline curve (Culprit)out frm the Heirarchy and putting in some other grp.

Rgds,
Isia
06-20-2008, 01:11 PM
If that is the script I am thinking of, the curve if skinned to two joints which when move, scale the curve.

The problem is occurring where the length of the curve is being normalized then plugged into the joints. I assume the equation is something like:

originaLength / currentLength = normalizedScale

To solve it, you would need to normalize the output from the first equation so that it is still in sync, if you will, with the scale of the character.

something like:
normalizedScale / characterScaleNodes.scaleAttribute = joint.scale;

If that doesnt fix it, then it may be that you need to turn off inherit transforms on the curve node. (Note: its on the transform node and not the shape node). If the curve is indeed being driven by skinning or another type of deformation, chances are it is getting double transformations. You can check if this is the case simply by moving the whole character with everything selected. If the curve flies off into space, then it is getting double transformations.

I do not know how the script is setting up the stretch, but chances are you just need to normalise it is an equation of some sort so it would need to be normalised.

Hope that helps.

edit: A few typos
Chinwagon
06-20-2008, 02:08 PM
Whenever you are calculating world space based values like curve lengths or distances, you should divide the value by the scale of your rig.
:¬)
CGTalk Moderation
06-20-2008, 02:08 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.