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Spline length for Smart Skin


TNT

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Didn't know wheather to post this here or in the TaoAM. I guessed here.

 

I'm working on some simple smart skin for a petal on a flower.

 

Is there a way to measure the length of the center spline before smart skinning and then while smart skinning so I can make sure the petal maintains its length?

 

Seems like it should be simple but I can't find how to check a spline length between two CP's.

 

 

Thanks,

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There is one plugin that measures the distance between 2 CPs. That's almost what you want. If that's good enough for you you can find the plugin here: http://sgross.com/plugins/plugin17/index.html

 

Thanks,

 

I loaded the plug-in you mentioned.

It does return a linear distance which could be helpful for some things.

 

What I am looking for is one that measures the spline length between two points taking the curvature thru any CP's between them into the calculation.

Maybe it is more correct to call it curve length.

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It might be easier to use bones to maintain the length of the petal. A bone never changes length unless you key that property. I assume smart skin is for when it bends in some way or the flower opens? A different approach might work better.

 

 

-vern

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It might be easier to use bones to maintain the length of the petal. A bone never changes length unless you key that property. I assume smart skin is for when it bends in some way or the flower opens? A different approach might work better.

 

 

-vern

 

Thanks Vern

 

I'm following the TaoAM tut for modeling a flower.

It kind of lays out the way they want you to make the flower handle deformations.

I think a couple more bones in the leafs and petals would work like you say and I thought about doing it but I decided to try to make the tut work the way it was presented.

 

The tut has just one bone for each petal.

There is no way to make a realistic bend I can find without the smart skin it instructs you to use.

As soon as you start pulling the CP's to get the right look you get the petal changing length.

 

I thought knowing and maintaining the spline length would make it pretty simple IF you could measure it.

 

The TaoAM stuff is really good and I am not knocking any of it.

I'm really glad I started stepping thur them.

I am learning a lot.

 

 

Thanks again,

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I think the TaoAM is to get your feet wet with some of the concepts. It isn't going to get too sophisticated or highly realistic. If you REALLY want to bend a leaf or petal and maintain the proportions a series of bones would be the way to go. That exorcise in the Tao gives you the basic ideas for expanding to bigger things. I think the plug in that measueres spline length actually does get the length of the spline including the curvature but basing length "by eye" would work too. The problem with point motion is that it's linear motion so the movement between the motion might not maintain length proportionally like using bones. The length of that spline might match at the ends of each motion might be the same but you would need multiple key frames between those points to maintain that length.

 

-vern

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I think the TaoAM is to get your feet wet with some of the concepts. It isn't going to get too sophisticated or highly realistic. If you REALLY want to bend a leaf or petal and maintain the proportions a series of bones would be the way to go. That exorcise in the Tao gives you the basic ideas for expanding to bigger things. I think the plug in that measueres spline length actually does get the length of the spline including the curvature but basing length "by eye" would work too. The problem with point motion is that it's linear motion so the movement between the motion might not maintain length proportionally like using bones. The length of that spline might match at the ends of each motion might be the same but you would need multiple key frames between those points to maintain that length.

 

-vern

 

 

I think you are right.

A bone chain would probably work best.

 

Also, good lesson about the in betweens.

I didn't consider the interpolation between the poses.

Makes sense once you think about it.

 

I am always amazed at what I learn in the forums.

 

Thanks,

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  • Hash Fellow

While researching another issue I found that Steffen Gross's Multiple Models on Path plugin does report the length of a spline path.

 

However it only works in the chor so I guess you'd have to put model in the chor and get the plugin to think the spline is a path.

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I loaded the plug-in you mentioned.

It does return a linear distance which could be helpful for some things.

 

I have the plugin now updated, so it's measured also the curvature distance between 2 cp's .

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I loaded the plug-in you mentioned.

It does return a linear distance which could be helpful for some things.

 

I have the plugin now updated, so it's measured also the curvature distance between 2 cp's .

 

PERFECT!

That is exactly what I was looking for.

Now I can use that to get a good idea if I'm changing the splines length when I move a CP such as during smartskin.

Thanks for doing this Steffen

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