Apple Motion 4 - Manual (Page 114)

Keyframe Basics
You animate an object by creating at least two keyframes for a parameter, such as
Opacity, at different points in time in a project. A keyframe is a point in time that records
any change in the value of a parameter. For example, to create an animation in which
an object is completely transparent at frame 1 and becomes completely opaque at
frame 120, you create two keyframes: an Opacity keyframe set to a value of 0% at frame
1 and an Opacity keyframe set to a value of 100% at frame 120. The image fades in from
0% to 100% over the 120 frames. The smooth, fade-in transition between the two
keyframed values is called interpolation.
All keyframes for a specific parameter (such as Opacity or Rotation) are positioned on
a line over time. Different values for the keyframes change the shape of that line and
create what is called an animation curve. The type of curve from keyframe to keyframe
(interpolation) can be changed to create different animation effects. For example,
keyframes set to Bezier create smooth transitions in values. Keyframes set to Linear
create straight lines between the keyframes, for sharper changes in value. You can
modify keyframes and their animation curves in the Keyframe Editor, located in the
Timing pane. For more information, see
Keyframes and Curves .
Keyframe Editor Controls
The left side of the Keyframe Editor contains a list of parameters. You can choose which
parameters are displayed in the list in the Show menu. You can also create custom sets
of parameters. This allows you to focus on certain parameters at a time. For more
information on creating and viewing parameter sets, see
Custom Parameter Sets .
There are a number of controls above the parameter list:
Show pop-up menu: Use the Show pop-up menu to select what is displayed in the
Keyframe Editor. The Show options include:
• All: This option displays all parameters for the currently selected object, whether or
not the parameters are animated.
• Animated: This option displays only the animated parameters and curves for the
currently selected object. This includes animation curves created by keyframing as well
as behaviors. This is the default setting. With the Keyframe Editor active, you can also
press the U key to choose Animated from the Show pop-up menu.
114 Chapter 2 The Motion Interface