Gimbal/Local /Rolling...

Hello everyone, I’m here to ask some advices about rigging and animation because I’m totally lost when it comes to this now. At least I thought I was able to understand most principles, but It’s not the case. It’s frustrating me quite a lot.

What I would like to know is :

  • When to use GIMBAL mode when we animate instead of local or any other rotation mode ? I thought animators always use GIMBAL mode but It seems It’s not really the case in the video I’ve seen till now, in fact I never seen them using this rotation mode. So if you could enlight me on this point…

  • The second thing is rolling bones, I notice they often roll the bone according their “needs”, although I don’t understand all the time why they change it, I did notice it doesn’t affect all the rotation mode, whereas gimbal mode seems to take in consideration these changes others don’t.

  • The third and last thing is I’ve heard about an Euler filter available in the curve editor, could you tell me when to use it ?
    Would you have any exemple video ? I heard It was needed when you have gimbal lock, in the case you use the rotation mode as Euler XYZ as exemple. Could you confirm this ?

I know that’s a bunch of questions, but that would really help me if someone could help me a bit on this subject.

Thank you.

Hi Kinrove,

1- Personally, I always animate with euler and in Gimbal mode, this way I understand my curve and I’m going into the graph editor.

2- When you rig, you want to Roll your bones so that the axes correspond as much as possible to the way you will usually rotate them and animate them. For example if you rig a finger, you want to make sure that one of the axes will be able to fold the finger. if the roll made the axes at 45deg from this normal bending, I would be very difficult to bend the finger while animating! On the image you can see the difference, and this is just by using the roll. And yes, it only affect the Gimbal mode, but I think it’s the most important one! :wink:

3- I never used it, but from what I know, all the good animation software have one function like that. When you are in euler, there is multiple way to arrive to the same position because of the order of the axes. So when we animate, we don’t think about it (and it’s not an easy thing to understand) and we end up with weird rotation and gimbal lock. The computer is able to look at what pose we want to achieve and to change the rotations so that we end up at the same position with less problem. But if I’m wrong, someone can correct me!

One thing that know I also start to understand with all this Gimbal thing is that… I think it’s the responsibility of the animator to setup the rotation order and not the rigger (the rigger might try to put the best one, the more useful one, but we might need to change it for specific animation). I’d like to know if others agree with me on that.

Hope it makes sens.


Thank you for your reply mathias.

I’ve watched a bit the humane rigging tutorial. In this one the author tells It’s better to use Euler when you have one or two axis used and Quaternion when you use all the rotation mode. Which avoid gimbal lock… It has as well some others advantages that I don’t remember honestly.

Thank you to confirm you most of time use Gimbal as rotation mode. I did some animations some years ago under Maya and I was pretty sure I was used to use that mode and for translation local mode. I had some doubts as It’s quite old…

I guess the only reason animator use Gimbal is because that mode takes in consideration the rolling (the axis) of the bone ? Or is there anything else ? (That might sound stupid as question but I prefere

Thank you as well for your exemple. If I understand well this one. We have to align as much as possible the axis of the bone with the mesh and play with the rolling option. To use the axis we want to have the bone bending correctly. I should try to play with this on a character already rigged and see what It does.
It has as well his matter if we setup IK chains I guess…

To be honest, if there is animators that use quaternion and tweak and polish their animation in the graph editor at the end, I would love to see how they do that. I’d love to have a tutorial about it.

Quaternion is vector based, which is good for computer. but for humans brain, it’s a bit difficult to grasp (well personally, I don’t lol).

Ok, here is an example, both cube have some keyframe on their rotation. One is with Euler, and other, Quaternion. Make sure that it’s on Gimbal with the rotation, so that you can see the axes.

Now go to one of these keyframe and in the graph editor, before you move a key on their y axis in the graph, imagine how it should affect your cube. Do that first for the Euler and then do it for the Quaternion…

After you’ve done that tell me which one you were able to predict how the graph would affect the rotation. :wink:

rotation_system.blend (443 KB)