How Do I Constrain A Nurbs Cv To Another Nurbs Cv?

[georgep1]

I have 2 nurbs curves and each are projected onto seperate softbody surfaces. I want the end point of one curve on surface to draw a line (nurbs curve) to the end point of the other curve on surface, and when I animate the scene and the softbody surfaces move and change shape, I want the line between the two endpoints to adapt so that the curve still runs from endpoint to endpoint. how would I do this?

[joojaa]

Are the curves going to be surface curves or not in the future?

[georgep1]

no, I was planning on duplicating surface curves to turn them into normal nurbs curves while maintaining their dependency on the surface. I probably should have mentioned that

[r1chard3]

QUOTE(georgep1 @ 03/14/07, 07:32 PM) [snapback]262218[/snapback]
I have 2 nurbs curves and each are projected onto seperate softbody surfaces. I want the end point of one curve on surface to draw a line (nurbs curve) to the end point of the other curve on surface, and when I animate the scene and the softbody surfaces move and change shape, I want the line between the two endpoints to adapt so that the curve still runs from endpoint to endpoint. how would I do this?

How about making a cluster for each CV? The clusters can then be grouped, parented, or contrained anyway you want.

[joojaa]

Well if you use duplicate surface curve a with history on maya will keep the relation n matter how it deforms. Anyway back to this problem. draw a curve form end point to end point and projecting using normal direction.

HOWEVR this said its not the shortest path, ofr that you will need quite high order mathematics, that are a bit over my math knowlege. (its not so much over that i couldnt see its solution but it s so much over that im estimating 3 years of math would do it )

[12monkey]

You can use hermite mel command to get all five needed CVs for the curve.
= hermite <0.5>;
startPoint and endPoint will be the two end points of your surface curve which you already have. And for the startTangentPoint and endTangentPoint, actually every nurbsCurve's first two or end two CVs will automatically define a tangent for you, you just need to multiply this tangent by -1 to reverse the direction and offset it to the end CV of your surface curve, then you get your tangentPoint. finally use the hermite to get the middle CV.
Now build your curve with these 5 CVs, and write an expression to update the curve each frame.

btw: it's just an idea, not tested yet, may be you should just try it

[joojaa]

Ah ok yes seems like i misundertood thw question a bit, if the zoo full of monkeys heres right . Then this is rather easy, make a linear curve form endpoint to endpoint constraint it by some mens such as a locator on curve. THen rebuld the linar curve to cubic and use project tangent on the both ends.