Rotation Inconsistency...
nakamuram002
Posts: 793
In DS 4.8.9.59:
I created a 1m plane.
Pic 1 -- If I rotate in this order: Z90, X45, all the rotations are consistently applied on the local axes.
Pic 2 -- If I rotate in this order: X90, Z45 it appears that the Z rotation is being applied on its global axis.
Can someone tell me how to make object rotations consistent, please?
Z90_X45.jpg
1920 x 1200 - 370K
X90_Z45.jpg
1920 x 1200 - 356K
Comments
Rotation is not commutative, at least using the three Euclidean axes.
What you're getting is called Gimbal Lock. The easiest fix, if you're manipulating a simple prop, is to create a null and parent the prop to it; that gives you the extra axis of rotation mentioned in the linked Wiki article. Things can get complicated if you're manipulating a body part of a figure, though.
Thanks Richard. I'm not expecting the same result, just consistent behaviour.
Gimbal Lock -- Is that a new DS feature or bug?
Neither...it is something I can remember happening in past versions. And as to being a 'bug'...if you want to count it as a bug in reality, then go ahead. Yes, you are manipulating something that isn't real, but are doing so in a mathematically 'accurate' way. So, the closer you get to simulating reality, the more real limits and real problems. And the rotation controls are pretty close to 'real'.