First of all, I was reading this in the Blender Manual and am unclear on something:
Each time you add a new bone, its default roll is so that its Z axis is as perpendicular to the current 3D view as possible.
If this is so, why is it that a ctrl left-click extrusion and an E-key extrusion produce different roll results?
Yes, Humane Rigging is awesome! I found the chapter on rotation types to be a bit overwhelming, so I am taking a temporary hiatus from that DVD to see if learning from some other sources/methods will help me get rigging to “click” in my mind. But yes, it has been very helpful so far, and I will return to it.
What you are really trying to achieve with bone roll is the orientation of the bone’s X and Z axes in relation to the Global axes, to get the hinge vector of those axes aligned as you require.
Why the Global axes? If the armature rotates relative to the World space it shouldn’t change the way it moves in relation to its root bone.
Although I think what you are saying is that X and Z are the most important axes.
Is it correct to state: bones should generally pivot on their X and swing in the direction of their Z?
Clock, your airplane rig is impressive!
I will follow your tutorial. Not sure yet if it’s over my head or just about right. I suppose I’ll find out.
Bones have a unique to them orientation. Their Y axis is always along the length of the bone. Since their X and Z axes are the only ones free to rotate, people speak of the bone’s “roll” to describe how the x and z axes are oriented.
This was very helpful.
I think the best way to actually ‘get it’ is to turn on bone axis display, and watch what happens as you arrange and manipulate and then pose an armature.
I did find this helpful as well!
It is sometimes best to actually use the bone’s Y axis as a hinge, since you can precisely place each end of the bone to mesh features.
If you are able to briefly explain why this is, I’d be curious to know.
Can you not precisely place each end otherwise? (Pardon me if I’m asking something obvious)