5.5

Table Of Contents
840Motion User Guide
Write On behavior in Motion
The Write On behavior provides a quick way to draw a paint stroke or outline on the canvas
over time. Write On lets you create a handwritten text effect, build the ever-popular old-
time serial travel map effect, create a hand-sketched alpha mask for a transition or reveal,
and so on. The Write On behavior can be applied to a paint stroke created with the Paint
Stroke tool or added to an existing shape.
You set the animation effect to draw, erase, draw and erase, draw in reverse, and so on,
over time. When you apply Write On to a filled shape with an outline, only the outline of the
shape is drawn.
You can adjust the Write On Shape behavior using the following controls in the Behaviors
Inspector:
Shape Outline: A pop-up menu that sets whether the stroke is drawn, erased, or drawn
and erased. Choose one of the following menu items:
Draw: The stroke is drawn over the duration of the behavior.
Erase: The stroke is completely drawn at the beginning of the behavior and is erased
over the duration of the behavior.
Draw and Erase: The stroke is drawn, then erased over the duration of the behavior.
Erase and Draw: The stroke is completely drawn at the beginning of the behavior, is
erased, then is drawn again.
Stroke Length: A slider that defines the length as a percentage of the drawn or erased
stroke. A value of 100% uses the entire length of the stroke, bounded by the First Point
Offset and Last Point Offset parameters. If Stroke Length is set to 50%, when 50% of
the stroke is drawn on, it begins to erase (from the beginning of the stroke) so only half
of the length of the stroke is ever displayed over the duration of the behavior.
Stroke Offset: A slider that offsets where the stroke begins on the shape. The value is
expressed as a percentage of the total length of the shape from the start point defined
on the shape.
Direction: A pop-up menu that sets the direction in which the stroke is drawn. There are
two options:
Forward: The stroke is drawn in a forward direction.
Reverse: The stroke is drawn in reverse.
Speed: A pop-up menu that defines the stroke’s “draw-on” velocity from the first to the
last point in the stroke. There are nine options:
Constant: The stroke is drawn at a steady speed from the first to the last point in the
stroke.
Ease In: The drawing of the stroke starts at a slow speed, then reaches and
maintains a steady speed through the last point on the stroke.
Ease Out: The drawing of the stroke starts at a steady speed, then slows down as it
gradually decelerates to a stop at the last point of the stroke.
Ease Both: The drawing of the stroke slowly accelerates from the first point on the
stroke, and then slows down as it gradually decelerates to a stop at the last point of
the stroke.
Accelerate: The stroke is drawn with increasing speed.