View Full Version : help whith orient joint

01 January 2005, 03:33 AM
hello friends. :)
Iīm a newbie in character setup.
I prepared skeleton....all good.but after investigating in maya of which local axis stops to make a good skeleton to animate is necessary to activate the option of display and setting.
oh..sorprise..i have a local rotation axis disoriented... :sad:
I`m very confused. I do not know if my skeleton is ok or no.
How I can recognize as it is ok or no? Specially when I conduct the operation of mirror joint, what considerations there is to take? axes of viewport of Mayan are "X" towards the right, "Y" upwards, "Z" towards the front ..
hopefully they can help me.:thumbsup:
thank you very much beforehand and happy year. I leave snaps them of the problem.
sorry for my poor english.

01 January 2005, 05:41 AM
The way I learned, X always goes up the axis of the joint. Using the orient joints command in the shelf editor pretty much does this for you. Then I'll usually have my Z axis going in the plus X direction, to the left if you're looking at the back of the character. Then, my Y either up or forward. You'll usually want to have your X value rotate the joint around it's length, then just simply try and use Z and Y for other rotations you might use.

Usually, for mirrored joints I'll have the axis oriented the opposite direction of those on the original side.

Sometimes I'll have to go in and tweak on a joint's orientation and change it a bit from say the X down the length approach, depending on how I need the joint to rotate. It's best to start out with X always down the length though.

Again, this is just what I've picked up from experience and what I can recall off hand, so I'm sure other people will have other methods and such to use.

01 January 2005, 02:51 PM
thank`s for you help me seven6ty.:thumbsup: say that for the hand, for example rotate it all axes:
Axe X loking back, Axe Z change to X axes and Axe Y allways up?
agh...sorry so much for this...really need help for understand the local rotation axes on skeletons.
I did the following thing:
it is incorrect certain?

hopefully they can help me, I need it :cry: :cry:
I leave it my skeleton.mb...
please, thankīs for before hand

01 January 2005, 07:57 PM
Re: Seven6ty.

Remember the circles on the wrists of my Mutant rig? I came across a problem similar to this when I tried to connect the rotation attributes of the wrist joints and the circles...they rotated in completely the wrong directions when I rotate the circles! :banghead:

There was only one solution I could think of to align them - rebuild the skeleton by plotting individual joints( as in creating all the joints one-at-a-time, not in a chain ). After that, I could then parent the lot one-by-one. All the axis should be the same... :shrug:

01 January 2005, 10:43 PM
Specially when I conduct the operation of mirror joint, what considerations there is to take?consider the plane over which you want to mirror joints and what do you want to achieve, that is how they will be oriented. in your case, you should mirror them with 'mirror across - yz' (as you did) and 'mirror function - behavior' (as you will do). ;)

also, check your skeleton for any possible redundant joints. if you intentionally placed them in shoulders/upArms, root/hips and thumbs than sorry, my fault. :shrug:

Remember the circles on the wrists of my Mutant rig? I came across a problem similar to this when I tried to connect the rotation attributes of the wrist joints and the circles...they rotated in completely the wrong directions when I rotate the circles! :banghead: it is a rule of thumb to have correctly oriented skeleton before connecting any of the controls to it. however, one fast fix for such situation as yours is to use multiplyDivide node to multiply the attribute/input values with -1.

cheers. :)

01 January 2005, 11:32 PM
hi friends...thank`s again for your support. :thumbsup:
the truth is .., I am preparing a skeleton for a robot for personal test only...:)
I continue working simultaneously and to be able to understand this.
friend ttesla...i reflect the bone in the axes YZ with behavior :) ... :thumbsup:
I leave screens them..
thank`s once again for your support. :thumbsup:

01 January 2005, 01:13 AM
Yo Boone. Yeah, I've had the same problem before, of the control rotating the joint the opposite way, and I believe it was just a matter of having to flip the joint orientation axis 180 degrees in Y I believe. Something like:

rotate -r -os 180 0 0;

And nolodos: I usually have my Z-axis pointed to the character's left, this usually being the main axis of rotation for the knees and such, but I'm not sure it matters too much if you change y and z, just as long as X is down the joint's length.

01 January 2005, 01:47 AM
I can rotate the model very well.....anyway, place ik handles and adjust and its movement is good...
but I follow without spite of being able to move the model....I ask myself, if there is a general rule that it indicates, for example the hands have such axis....las legs must have such axis so that their rotation is much better..etc.. that has to me intrigued.
sorry for my poor english..
cheers an thankīs again friends :) :thumbsup:

01 January 2005, 03:26 AM
From the pictures, looks like you created the joints with Auto Orient turned off and mirrored based on behavior. Mirroring based on behavior is correct (for joints meant to me orientated and not translated as yours are). I would recreate the skeleton with auto orient on and fix the misalligned joints, it'll be less work than re-orientating all of them.

Use joint orient and not the axis to orient your joints. Joint orient works better.

Lots of people have hard-core opinions on which axis points down the bone. I personally don't care as long as you're consistant. If you're using X down the axis, make ALL your joints X down the axis.

I have a doc up on my website, that has what I think are good guidlines for rigging. Keep in mind, they're guidlines, not rules, but if you're new to setting up rigs they should help.

01 January 2005, 04:27 AM
Well, like I said, only rule I could think of would be the X-axis along the length, then after that, you can just think that you are trying to align the Y and Z axises as close to the world Y and Z axis as possible, that's one way of looking at it. Although, like I said that isn't even so much important as just the fact that you want to have it the same throughout your model, it just makes it easier on you. So if you rotating it in the positive Y axis raises your upper arm bone on the left, it would be nice to have the same thing on the opposite side... Especially when you get to the point where you are writing scripts to automate some of this and all of that. Anyhoot, good luck!

01 January 2005, 06:43 PM
Re: ttelsa.

Ahhh...those things called "nodes" Cheers! :)

Re: Seven6ty.

Hmmm...those things called "rotations" Cheers! :p

01 January 2005, 01:10 AM
really very interesting....
thankīs for yours answers
i have done the following :
I made the bones in front viewport for the spine with orient enable xyz (+y second axis world) :), then, the bones for the legs and the bones for arms, i did them in combining the top and left viewport ..:)
and result is the following :

now, taking the consderations from you on orienting the bones, itīs like this :
I hope that the direction is correct the this time.....if no... :cry: :cry:
thank`s again brothers of maya with this newbie animator :thumbsup:

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