[Benedict A. varga]

Wow! You clearly have no idea what you’re talking about. Ok, I’m wasting my time here. Let me know when you learn MATH. :-/

[Benedict A. varga]

I’m trying to make a corrective morph for my character’s shoulder that’s driven by distance instead of rotation. Since a shoulder joint rotates around all 3 axes it seems to be almost impossible to drive a morph by the shoulder joint’s rotation.

It may not be a perfect solution but I think it may work. I need to test it out and see the results. Of course I could be completely wrong but I can think of a lot reasons why I’d like to know how to do this that has nothing to do with joints or corrective morphs at all.

Anyway, I think I maybe close to figuring this out. (hopefully…sort of.)

I’m trying to put the equation from this site

https://mathinsight.org/distance_point_plane

into XPresso nodes and I think I’m pretty close.

[Benedict A. varga]

Ok let’s see if these images better illustrate what I need help with:

Also in the example above where I show the distance going from 0 to 50.628 is only working because I’m calculating the distance between the neck and elbow joint along the global y position. The second I start rotating any of the spine joints below the neck the distance will obviously change which isn’t what I’m looking for.

Anyway, I hope this explains things better and thanks again for trying to help. 🙂

[Benedict A. varga]

Thanks for the response but this was what I was afraid that I wasn’t being clear about.

I’m trying to determine the distance between 2 joints on the first joint’s positive z axis only.

If you move the Joint.1.Goal along its x or y axis in the example you provided you will see the result continue to change.

Hmmm. I think I may need a pict to illustrate the problem. I’ll post an image as soon as I can because I really need help on this.

I do appreciate your effort to help me though. 🙂

[Benedict A. varga]

You are AWESOME!!!

😀

EXACTLY what I needed!

Thanx!

My boss thanx u too…

He just doesn’t know it yet…

😉

[Benedict A. varga]

Hey Brian,

Thanks for responding. Yes, that example is sorta what I’m going for but the difference in the pictures I posted is that I have a bunch of joints attached to the spline with an IK Spline Tag.

Here’s a link of the scene in the pictures and how I have it set up. (Let it play a couple of times and you’ll see the joints in the middle of the chain start twisting. Note that you need Mocca for this to work.)

https://download.xdrive.com/s/351508300Es34zcStVQ6IRBYhLGc&partner=plus

The geometry is weighted and being deformed by the bones.

It’s not important really, I just kinda see a benefit of being able to deform models with joints attached to a hair spline. (i.e. – chains, coat tails, hair that’s modelled to look like clay, etc. – basically objects that aren’t perfectly cylindrical in shape.)

I’m guessing the problem is that points on a spline don’t actually have a coordinate system and that’s why I can’t make the joints attached to them maintain their orientation…but that’s just a guess.

Anyway thanks for trying to help! 🙂

[Benedict A. varga]

Sorry it took so long to respond…

Your instructions worked like a charm!

Thanks a bunch! 🙂