Get the Angle of a Joint Chain (3 Joints)

#1

This has been discussed before in the following threads:
Here and Here

Unfortunately, all those matrix jargon is just way over my head.
Luckily, ThE_JacO (Cult of Rig) provided a demonstration of it in a screenshot.
But I can’t quite put it together since the parameters were not exposed. Basically, I can’t figure out what specific value is plugged from the decomposeMatrix node to the[b] plusMinusAverage node

[/b]You can see an illustration of the problem here: https://www.dropbox.com/s/ugpsfpffq7ao8u9/MYA063_joint_chain_angle.jpg?dl=0

You can also see an illustration file here: https://www.dropbox.com/s/ag03n1ezow6xpel/MYA063_joint_chain_angle.ma?dl=0

As you might know, it is not working properly. My locator should have a rotation value but it only has zero.

Is there a way around this?

Thank you for taking the time to look at the problem.

#2

Ok, i’m not sure what it is your asking really, and this may be the dumbest thing i’ve typed out here. But if you look at the plusMinusAvg node, next to the input there’s a [+] sign, if you twirl that down you’ll see the attributes that are being fed from the decomposeMatrix node. The same with the output from your decomposeMatrix node. That way you can see what is being plugged into what. Is that what you’re asking? I’m assuming not. Unfortunately i’m not in front of maya to help further, i’m sorry for the lack of help here, just hoping to point you in somewhat of a direction.

#3

Hi Remi. Thanks for the reply.

Here is the problem, I can’t “twirl that down you’ll see the attributes that are being fed from the decomposeMatrix node”
The right is a reference image. That was my problem all along because I can’t see the exposed parameters.

Hope that clear things up.

#4

Just to update,

greentooth from polycount referred this video: https://vimeo.com/64958089
which what exactly what i need.

Hope it will someone else too