Null Rotation

[Hutch]

Why do nulls rotate differently than bones? If I rotate a bone in the x axis the z rotation stays the same all the way around. If I rotate a null in the x axis the roll handle flips from 0 degrees to 180. Is there something I can do to make this stop? I wanted to orient a bone like a null because the null is easier to select but when it flips the z axis it screws everything up. I also need to be able to manipulate the roll handle so locking out the z rotation is not an option.

[Gerard]

Hutch,

 

It has to do with the default roll methods that bones and nulls have. Bones default to what's called Z-singularity while nulls default to Y-Poles-Singularity.

 

If you go into the properties of the null you can change the method.

 

Under the properties triangle of the null you will see the Roll-Method option, if you now left click on the "Y-Poles-Singularity" that appears to the right of this, you will get a drop down box with the three roll-method options to choose from. Select the Z-Singularity option to make the null rotate like a bone.

 

Gerard

[Hutch]

Thanks Gerard! As long as I rotate the null with the rotate manipulator or from the properties window, Z singularity works just like I wanted. If I try to do a full 360 degree rotation in x axis by moving the tip of the bone, it seems to do a 360 in the Z axis from around -175 to 175 in x. I can live with that though, thanks alot.

[3DArtZ]

Hey Hutch, that's what I do. I just put the null into rotator mode and all is cool.

 

Mike Fitz

www.3dartz.com