Rotation Types

The animation module provides a dozen rotation types or ways to rotate or align an Actor.

Tween - The rotation of the Actor is interpolated linearly between its rotation at the first keyframe and its rotation in the last keyframe of the timeline. Simply put, in half the time it will have made half the rotation.

Smooth Tween - The Actor's alignment will accelerate between keyframes to give a smooth rotation. This creates much more natural motion. Used with a camera, for example, it will produce a realistic panning action with ease-in and ease-out. Hint: Use a single frame key following the end of the pan to prevent overshoot.

The last three types of rotation require that the Actor Aligns To, Looks At, or Mimics its rotation from another Actor. Specify the Actor to be Looked At by clicking the Select button in the Target box. After an Actor has been selected, the radio buttons for the Looking At options will be enabled.

Align to Path - If an Actor is following a path, then this sets its rotation to follow the direction of the path. For example, a plane following a path can be made to turn as the path turns.

Look At - The Actor is forced to point at another Actor. The actual point of aim is the selection handle or Model Center of the targeted Actor.

Mimic - Give this Actor exactly the same alignment as the targeted Actor.

Internal Rotation - There are a few special rotations that are difficult to arrange manually, quite commonly desired, and are best described as 'internal motion'. The buttons in the box marked Internal Rotation give a quick way of specifying motions that are 'internal,' that is, relative to the Actor, no matter what other actions the Actor is performing. The rotor blades of a moving helicopter are a good example of internal rotation. The Actor's direction can still be specified in its key frames, while the internal rotation is 'underlaid' on the tween.