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ljilekor
08-02-2007, 11:54 AM
Is it possible to animate the EP's on a curve?



Animating with the CV's is not very handy nor precise... So I'd like to animate the EP's instead. I can't create a clusterdeform on an EP of a curve.

Can't believe that there isn't a way to pull this off in Maya(The RollsRoyce of 3DTools).

Thx.

BoostAbuse
08-02-2007, 05:46 PM
Why not just create the clusters in your CV's of the curve? If it's not precise then you can always adjust the number of CV's and use the component editor to give you more precise and smoother results. Unless you feel like creating a series of joints and binding them to the curve, editing in the component editor and attaching individual controls.

-s

visualfx
08-02-2007, 06:41 PM
Take a look at the "Deform=>Point On Curve" menu option. This sets up a leastSquareModifier and a connected locator. The leastSquareModifier node forces a specified point on a curve to always pass through a the connected locators (or array of locators) position/s.
I setup a quick test of placing these point on curve deformers at all the edit point positions along the curve. It seemed to perform as expected, though for a degree 3+ curve you need to attach an extra point on curve deformer at each of the curve points nearest the second and second last CV positions (end tangency CV's).

The test involved a degree 3 curve with 4 spans and a u-coord range of 0-1. I attached point on curve deformers to u-coord values of {0.0,0.1,0.25,0.5,0.75,0.9,1.0}.

Hope this helps...

ljilekor
08-03-2007, 10:53 AM
Thx guys

Why not just create the clusters in your CV's of the curve? If it's not precise then you can always adjust the number of CV's and use the component editor to give you more precise and smoother results.

Animating with CV's (BSplines) sux completely. For precise, predictable and versatile animating, one wants the curve to pass through the control point! E.g. Imagine you have to fit a thread through an animated needle... BSplines will be very hard to manage while it's easy to predict that a pointconstrainted EP will do the trick.:curious:

Take a look at the "Deform=>Point On Curve" menu option.

:bowdown:
Aaaalelujah,
Aaaalelujah,
Alelujah, Alelujah,
Aleeeeeeeeeeeeeeelujaaaaaaaaaaaah...
:buttrock:.

visualfx
08-03-2007, 04:12 PM
I'm glad that worked out for you...

If you're interested, I thought of a much better way to acheive a similar result.

Start with a degree 1 curve, placing all the cvs where you want your edit points to be. Then create a fitBspline node, now attach the original curve shapes ".worldSpace[0]" (or alternatively the ".local") attr to the fitBspline ".inputCurve" attr. Create another arbitrary curve of degree 3 ...now connect the ".outputCurve" attr of the fitBspline node to the ".create" attr of the new curve.
The new curve will now be driven by the original degree 1 curve, so cluster/constrain the cvs how ever you want.

This should actually work out to be a much more elegant solution than the one I described above...

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