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As a 3d character animator I try to use Quaternions on very few bones, the problem with Quaternions is not being able to edit the curves as a 1 to 1 understandi

As a 3d character animator I try to use Quaternions on very few bones, the problem with Quaternions is not being able to edit the curves as a 1 to 1 understanding of the axis. I mainly use the Quaternions for IK handles and the Root bone, the things that will rotate more than 360 degress.

mkl 8y ago
> the problem with Quaternions is not being able to edit the curves as a 1 to 1 understanding of the axis Can you expand on this? What is the curve representing, and which axis do you mean?
- kilpikaarna 8y ago
  Not the GP, but by axis they mean XYZ euler angles. In 3D animation software you typically have a set of curve graphs that show transformations vs time, that allow the animator to tweak timing, ease in/out of keyframes etc. If your object has its rotations animated as a quaternion you effectively lose this functionality, because the individual XYZW components of the 4D rotation don't correspond to anything intuitive in 3D space. So typically you want to keep your rotations in euler angles except in the special cases when you run into gimbal lock etc.
  - mkl 8y ago
    Okay, let's see if I have this right. The rotations are animated by manipulating the graphs of three functions of time, the values of which are the amounts of rotation around each coordinate axis? The only rotation animations I've made have been done with code.
    - kilpikaarna 8y ago
      Pretty much. Usually you do the rough animation by manipulating the objects in the 3D viewport (with the manipulator using euler angles even in the cases where the angles are then converted to and stored as quaternions) and marking keyframes. The graph view is then useful for tweaking the interpolation between keyframes, minor adjustments, copying and pasting keyframes and such. The graphs are time on X against rotation/translation/scale amount on Y, yes, with separate graphs for each axis.

mkl 8y ago

> the problem with Quaternions is not being able to edit the curves as a 1 to 1 understanding of the axis Can you expand on this? What is the curve representing, and which axis do you mean?

kilpikaarna 8y ago
Not the GP, but by axis they mean XYZ euler angles. In 3D animation software you typically have a set of curve graphs that show transformations vs time, that allow the animator to tweak timing, ease in/out of keyframes etc. If your object has its rotations animated as a quaternion you effectively lose this functionality, because the individual XYZW components of the 4D rotation don't correspond to anything intuitive in 3D space. So typically you want to keep your rotations in euler angles except in the special cases when you run into gimbal lock etc.
- mkl 8y ago
  Okay, let's see if I have this right. The rotations are animated by manipulating the graphs of three functions of time, the values of which are the amounts of rotation around each coordinate axis? The only rotation animations I've made have been done with code.
  - kilpikaarna 8y ago
    Pretty much. Usually you do the rough animation by manipulating the objects in the 3D viewport (with the manipulator using euler angles even in the cases where the angles are then converted to and stored as quaternions) and marking keyframes. The graph view is then useful for tweaking the interpolation between keyframes, minor adjustments, copying and pasting keyframes and such. The graphs are time on X against rotation/translation/scale amount on Y, yes, with separate graphs for each axis.