Keyframes (or keys) store poses and positions of the character that have been set by the animator.
On the timeline, the key frames are marked in dark blue
To create an animation, it is required to create keyframes and change the position of objects in them.
- Open the test scene Chibi jump
- Increase the number of frames in the scene to 100
- Select frame 80
- Press the button to create a key (F)
- Switch to the point controllers mode
- Change the pose of the character - for example, let the chibi raise its arms.
The frames that are between the keys are called interpolation frames.
The intermediate positions of the objects are automatically calculated in these frames.
Depending on the type of interpolation, the behavior of the object between the keys will change.
Let's take the animation with three keys as an example!
With the Step interpolation type, the intermediate positions between the keys will not be calculated: in each frame there will be the same position as in the previous key.
With the Bezier interpolation type, objects will move between the keys on arcs with smooth accelerations and decelerations.
With the Linear interpolation type, the trajectories of objects will be straight lines, and their speed will be even.
There may be different types of interpolation at different intervals. Each interpolation type is marked with a color on the timeline.
If there are several different interpolation types for different objects on any interval, the interval is colored pink.
In the previous exercise you added a new key at the end of the Chibi_jump animation. Now the interpolation type between the last and second to last keys is Step, so no intermediate frames are calculated.
- Select any frame between the 67 and 80 keys.
- Open the interpolation selection scroll
- Choose Bezier interpolation
- Watch the animation
In addition to the type of interpolation, you can also set the type of behavior of the character's body parts for the interval.
The default setting is IK (inverse kinematics). With this type of kinematics, the character's limbs move from the palms or from the feet.
In this example, the palm point moves to its position in the next key along the shortest trajectory, which causes the arms to bend at the elbows.
However, in this case, it is more appropriate to rotate the whole arm from the shoulder.
For such cases, we recommend using FK mode.
- Press the + button next to the Chibi track name to open sub-tracks (more details about working with tracks will be described in the next tutorial)
- Select the Arms track
- Select any frame on the Arms track between keys 67 and 80.
- Open the Kinematics Type scroll and chose FK.
- Watch the animation.