Adjusting Local Rotation Axes on a Skeleton
in Maya 5:
1. Select all the joints by dragging over them all in the
Hypergraph or selecting the root “hip” joint, and typing
“select –hi;” into the command line.
2. Go to Display > Component Display > Local Rotation Axes
3. Go into component mode.
4. Select the question mark icon, right click on it, and make sure Local Rotation
Axis is checked off.
5. Use the arrow tool to select a local rotation axis of a joint. The local
rotation axis should turn yellow.
6. Use the mel script command, “joint –e –oj zxy;” to
adjust the local rotation axis. This tells Maya to orient the z-axis down the
bone.
7. Note: if you move a joint with the Translate tool, after setting the local
rotation axes, you’ll throw it and all of its child joints off and will
have to repeat the above steps on all of the messed up joints. You can, however,
rotate the joint without throwing off the local rotation axis.
8. Now, make sure all of your x’s or y’s are pointing in the same
direction – as much as you can get them pointing in the same direction.
You can use another mel command, “rotate –r –os 0 0 180;”
to get a Y axis to point in a direction 180 degrees from what it is pointing.
I used this a lot.
View the screen shot of my "zxy" quadruped skeleton with properly aligned Local Rotation Axes. Note all of the blue z axes point down their bones, and all of the green y axes point to the dog's left side.