Understanding additional joint options

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There are a couple of other options which you

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might find useful when building your joint chains.

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The first is symmetry.

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This is off by default.

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But when active,

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this will automatically create the joints on the

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opposite side of the character for you.

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This is what happens with it disabled. As you already know

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if I set this to x axis, it will mirror the joints along the X axis here.

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If I create the joints, now you can see the opposite side has been created too.

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What's even better is we can move this side

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and the other follows.

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So it's a proper mirror image,

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we can rotate it too and it follows.

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So you can see how this could help speed up the process of building a skeleton.

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Let's create another and mirror across the Z axis instead.

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And that's done

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if we look in the outliner. Now you can see that the opposite skeleton

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has symmetry constraint nodes attached,

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which are what makes the symmetry work.

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The problem is these also lock the joints so you can't rotate them or translate them.

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You can see they are locked by a direct connection with the yellow tags.

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On the channel box.

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So they will only follow where the original joints lead them

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if you do want to get control of them.

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Again, all you need to do is delete the constraints

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that grants them their independence.

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So you were then free to do what you like with them.

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There's one more area I want to quickly talk about concerning joint creation

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and that's the projected centering option.

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What this will do is automatically place the joint in the middle of the model.

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If we look at the arm

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with this enabled,

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I can simply click on the shoulder to place a joint

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and mayor will work out the central point of the model.

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For me,

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it would help if we could see the joints.

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So let's just enable x-ray joints so we can see the joints through the model.

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OK. That's better

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there, it is a tiny joint.

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Now let's create one for the elbow

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and finally another for the wrist.

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So there you can see Maya has done a pretty good job of placing these joints for me

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where this tool really shines though is with fingers.

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Ideally, I'd show the wire frame so I could see where the knuckles are,

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but this is just a demonstration.

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So that's one finger done.

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OK. Let's create the others

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as a tip, you can press G to jump back into the last tool you used.

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So in this instance, I can just press G

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to reactivate the joint tool

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and that's the thumb done.

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Ok. That's the joints for the hand done.

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Yes,

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we would need to go in and adjust them further

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and also make sure they are orientated the right way.

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But this gives us a good starting point

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with areas like the arms, legs and fingers, the tool works well,

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but it does fall down when attempting something like the torso.

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I'll just create a few quick joints to demonstrate,

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As you can see from the front, they aren't aligned correctly.

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Ideally, we need them straight.

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So in this instance,

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it would be better to create them with projected centering disabled.