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KentYang
08-17-2010, 02:51 AM
Hi, everyone

I get confused about the term "rotate order" when I learning Maya leg rigging techniques. I was told that it's quite important, but I don't see any different between rotate order as xyz or xzy.

Can anybody give me a proper explaination about this term? How do I test the difference? Thanks a lot!!
By the way, what's your favorite setting for rotate order?

PS. I've checked the Maya documents, but still don't get it. ><

mduvekot
08-17-2010, 01:52 PM
Here's an example.

KentYang
08-23-2010, 06:40 AM
Thanks for the file.

I have checked it, but still don't get it. (Sorry~my problem...)
Here is a sentence I quote from the Maya help: " if the rotation order for an object is set to xyz, the object first rotates about its X-axis, then its Y-axis, and finally its Z-axis. Default is xyz. "
When it says "its", it means the object's local orientation, right?
From the file you gave me, every model rotate the same direction (along X axis) from fram1 to frame24 even if some of them were set to "ZYX" or "YZX" in the order setting. This is the part which confuses me. :sad: (Shouldn't them rotate along Z or Y axis first?)

I did see the effect of different rotate order drive different rotation result, but still have no idea about why or how it happens?
Sorry, but could you explain a little bit more about the concept of "rotate order"?
I appreciate it~

djx
08-23-2010, 12:49 PM
Maybe you will get a better understanding if you turn rotation mode to gimble.
Now when you rotate along any axis you can observe how the other two axes behave. Depending on the local axis rotation order the other axes may move with the one you are rotating or just stay where they are. Thats why it is important. For some joints you want to rotate along one axis and not move the other two depending on what the joint needs to do. Have a play in gimble mode and you will see the effect.

David

Polimeno
08-30-2010, 05:29 PM
...I don't see any different between rotate order as xyz or xzy.


First of all, choose the gimbal mode as djx said before.

In my opinion If you think about rotate orders as a simple 'parent operation', it would be much easier to understand it. Example :

Leave your rotate order as default XYZ. First, you read it backwards:

Z
'-> Y
'-> X

X is a child of Y who is a child of Z.
Rotating X affects nothing, but if you rotate Y it should affect X and as expected Z would affect both.

Now set up the rotate order as ZYX.

X
'-> Y
'-> Z

Z is a child of Y who is a child of X.
Rotating Z affects nothing, but if you rotate Y it should affect Z and as expected X would affect both.

hope that helps,

isoparmB
09-11-2010, 04:00 PM
In addition to what's been said, in practical terms I've found that the first axis in every rotation order option is the axis that is the least likely to flip. This is useful when you want to base a particular axis of a joint as the driver for a set driven key setup, or as part of an expression.

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