5.5

841Motion User Guide
• Decelerate: The stroke is drawn with decreasing speed.
• Natural: The speed at which the stroke is drawn along the path is determined by the
shape of the path. For example, if the stroke is a U-shape curve, the stroke is drawn
along more quickly as it moves toward the low point of the U, and more slowly as it
moves up the edges.
• Recorded: This option appears only if there’s a recorded time over which the stroke
was drawn. In other words, if a shape is converted to a paint stroke, this option does
not appear. If the paint stroke is created with the Paint Stroke tool in the toolbar
(using a stylus or mouse), this option does appear.
• Custom: Lets you draw the stroke along its path by setting keyframes for the stroke’s
speed from 0 to 100%. In other words, you determine which portion of the stroke is
drawn along its path in time.
• Custom Speed: A slider that becomes available when Speed is set to Custom. You can
modify the Custom Speed velocity curve in the Keyframe Editor. For example, you can
keyframe custom values to draw a stroke forward to a specific percentage of its path,
then backward, then forward, and so on before it reaches the end of the animation.
• End Offset: A slider that offsets the end of the behavior inward from the defined Out
point and holds the last value. In other words, it offsets the visible paint stroke from the
end of the path of the stroke.
Keyframe shape control points in Motion
You can keyframe the control points of a shape. When you do so, the changes are recorded
to the Shape Animation parameter, visible in the Keyframe Editor. Keyframes added to the
animation parameter affect all the shape’s control points simultaneously.
The process used to animate both masks and shapes is identical. To see an example
of mask animation, see Rotoscope a mask’s shape in Motion. For more information on
keyframing in general, see Intro to keyframing in Motion.