Although I found plenty of information and really awesome tutorials about rigging, skinning and animation, I ran into some problems on the way to my first animation. So in this posting I list all my problems and the solutions / workarounds I found for them.
Failing To Insert Key Frames
With a very simple mesh and a 5 bone armature attached I was unable to insert any key frames. Pressing the I hot key leads to messages like either “No suitable context info for active Keying Set” or “Keying Set failed to insert any keyframes”.
It depends on the setting in the dropdown list “Active Keying Set …” in timeline editor.
If “Available” is set, the I hotkey does only work for bones having already an entry in the F-curve editor but failed if it is there very first key frame for this object. Delete it and it will do. But this is a nice feature if you have set up all objects you are interested in at the first frame and want to add frames for exactly these bones. Then you can pose your armature for a new frame, select all bones, hit I and only the relevant key frames will be inserted i.e. no new ones are created.
“ButtonKeyingSet” lets you insert keyframes via right mouse click in Properties panel if you hover the mouse over rotation, location, … Other predefined keying sets like LocRot, … do what they are supposed to do namely inserting works but is limited to what you have chosen.
No Interpolation of Key Frames
Having a basic understanding I started experimenting with a simple walk cycle. Setting up the start position (contact frame) at frame 1 I copied the pose and pasted opposite pose at 13 and same pose at 25. But my first run wasn’t smooth at all: Staying at the contact pose for the first 12 frames and switching abruptly to the next pose in 13 and keeping it for the next 11 frames. Finally I found out that my user preferences / Editing / New F-Curve Defaults were set to constant instead of bezier:
The same applies to the curve interpolation type in F-Curve editor.
Strange Behaviour on Pasting X-Flipped Pose
If one or more bones seem to behave weird when using Copy Pose / Paste X-Flipped Pose check first which coordinates are affected by the inversion. Bones that behave correctly should shown an inveision of the sign in X direction only. If you see numeric changes of the Y or Z coordinates, there is something wrong with your Bone Roll. Go in edit mode and look at Properties (N) / Transform / Tail:
If you see a value unequal to 0°, the paste pose operator won’t operate correctly when in flip mode. Try to set it to 0 … and test carefully, whether there are any side effects on other actions. If there are side effects you have decide if the it’s worth the trade-off. If not you have to manually correct the pose after pasting.
Pasting X-Flipped Pose Cannot Be Applied on Several Keyframes at Once
Pasting X-flipped pose is meant to work on the currently selected keyframe and the selected bones only. If you want to mirror a whole action or a part of it, you need an add-on. Look at Flip Animation Add-On for Mirroring Keyframes in Blender for more information how to achieve this.
Copy And Paste in Dope Sheet
Copying and pasting keyframes in dope sheet appears to be somewhat strange in the beginning because it refers to selected channels. This might be different from the bones selected in 3D view and even from keys selected in dope sheet:
|Copy and paste →|
Especially when switching between different actions this is irritating because channel selection is stored within an action. So make sure that the appropriate channels are selected in your target action. The easiest way to achieve this is hovering the mouse over the channels and press a to select them all. But note that the dope sheet follows any selection change done afterwards in 3D view.
Things to Remember
Maybe this sounds silly but I came across these issues more than once.
- Given the case you want to split your animation into two (sub-) animations. For example a jump animation has to be split into a preparation and a flying phase. Take care to disable Only Insert Needed in user preferences when defining the transition frame. Otherwise your animation will show unexpected behaviour.
- Clear Parent for bones does not not work in pose mode but in edit mode.
- Pivot point settings apply to pose mode as well. If your rotation suddenly behave strange check whether you’ve changed pivot point before.