Getting the current angle/s of a CharacterJoint

Unity Engine
1

Hello,

I have not found an answer to this and related postings, so I would really appreciate a clear answer (as I’m sure others will too).

I am using CharacterJoints with a ragdoll, and want to implement a controller to bring the ragdoll ‘to life’, i.e. moving the joints about.

I would like to know:

How can I obtain the current angle of rotation of the joint at runtime? Can someone clarify exactly how this works in unity with a CharacterJoint, bearing in mind that it has the potential to rotate around 3 axes?
e.g. why is there not a joint.angle1/angle2/angle3 method or property?

I’m sure there is a sensible answer, and I admit I am slightly confused between local/world coordinates etc. If there is no direct way, what exactly is the way to work it out?

FYI, my controller for each joint will take 1, 2 or 3 axes (since I think I am aiming for twist, swing1, swing2 axes) and output a value from 0…1 for each, which represents the desired angle of the joint in that axis.
My goal is therefore to take this 0…1 value and first map it to a desired angle (in degrees) from the appropriate minimum and maximum range (exactly how to obtain this, versus just using the adjusted parameters in the Inspector, I am also not clear on). To compute the torques required to move the joint to the desiredAngle, I need to know what the current angle is (for each axis), and it is this which I cannot do.

Thank you very much indeed for any suggestions.
Greg

2

As you say, there is no angle property that just lets you read the angle of the joint directly. If the attachment positions of the joints are arranged in a consistent way, you might be able to calculate the angle using Vector3.Angle. Say if you have it arranged so the joint’s length is always along the Y axis, you could get the transforms of the parent and child object and use something like:-

angle = Vector3.Angle(par.transform.up, ch.tranform.up);

Not ideal, but it might solve your problem.

3

Thank you but as you have suggested this doesn’t sound like a very satisfactory option, surely there is a more standard/straightforward way to do it?

4

I’m fairly sure there isn’t an easier way, but you could try sending an e-mail to support (support@unity3d.com).

5

Okay I will do but in the mean time surely someone out there has tackled this problem before??

Thank you again for any further help.