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View Full Version : Your method for setting Rotation Orders?


mlefevre
11-26-2008, 02:24 PM
Hey,

I have a couple of questions with regards to rotation orders. I use Maya, but I guess it applies in most if not all of the applications.

How do you guys go about setting rotation orders up for character controls? Do you set them as you work through a rig, or set them up at the end?

Do you set the rotation orders on the joints as well as the controllers?

Do you think it's better to give the animator a choice of rotation orders on each control?

Can changing rotation orders break the rig, with things such as IK/FK snapping?

Thanks!

MolemanSD7
11-26-2008, 03:48 PM
You can set them up either during or after the rig is made, but I prefer to set them as I'm going. Once you set the rotation order, leave it...don't switch it, or it will really mess with your controls in animation.

As far as setting them, the main purpose is to avoid gimbal lock. So, find what the main axis of movement would be, and make that the axis that will cause the others to move with it when rotating (you can see this if you go into gimbal mode on the rotation tool). The next axis should be the second most important, then thirdly the least important one should be the one with rotates without affecting the others. Now, I'll explain this a bit more.

Say you're setting up a shoulder control for an FK arm. The character's bind pose is a basic T-pose, facing down the Z axis. The main axis will probably be to raise and lower the arm to the side, so the Z axis. Then, in a walk, the forward to back axis will be prominent over twisting. So, the Y axis is next. Finally, the twisting motion, or the X axis. So, you want the Z to drive the Y and X, the Y to drive the X, and the X to only drive itself. So, since maya evaluates these in a reverse order, set the rotation order to XYZ (I know that bit is confusing, but its how I was taught, and so how I think of it. Prominence from right to left).

Or, for a torso, per se, the main movement will be the curling and arching of the torso, followed by the twisting, then the side crunching, etc. The best way to check, is to set up the rotation order, try to animate with it, and see how often you hit gimbal lock, which is basically when you only have two axis to choose how to rotate from, because one axis lies directly on top of another. Hope this helps.

Leffler
11-26-2008, 08:39 PM
I use the script from jason schleiffers shelf for the AFR-dvds which sets rotation orders for everything that is selected, superhandy!

stewartjones
11-27-2008, 12:38 AM
I set them as I go. Then at the end I give the character an animation test and change any that I feel would be better for the situations the character will be in. (All of this before sending to the aniamtors though. Switching rotation orders after they start animation is not cool!)

mlefevre
12-02-2008, 06:52 PM
Thanks for the replies :) Very helpful.

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