Adobe After Effects CS4 - Manual (Page 621)

615 USING AFTER EFFECTS CS4
Effects and animation presets
Last updated 12/21/2009
Random Seed An input value for the random noise generator that is the basis of the Lightning effect. If the random
movement of the lightning interferes with another image or layer, enter a new value for Random Seed until you find
one that works for you.
Blending Mode The blending mode to use to composite the lightning on top of the original layer. These blending
modes work identically to the ones in the Timeline panel.
Rerun At Each Frame Regenerates the lightning at each frame. To make the lightning behave the same way at the same
frame every time you run it, don’t select this option. Selecting this option increases rendering time.
Path Text effect
If you are working on a project that was created in an older version of After Effects and the Path Text effect is applied
to one or more layers, you can continue to use the Path Text effect; otherwise, use text layers for greater control over
text formatting and text animation. (See “
Creating and animating text on a path ” on page 363.)
The Path Text effect lets you animate text along a path. You can define a path as a straight line, a circle of any diameter,
or a Bezier curve. You can also import a path created in another application, such as Adobe Photoshop or Adobe
Illustrator. The Path Text effect can work with nonsquare pixels, adjusting both character shape and path shape
accordingly.
This effect works with 8-bpc color.
Note: If you use Adobe Type Manager (ATM) and large text looks blocky or doesn’t otherwise render properly, increase
the Character Cache Size in the ATM control column.
When changing the shape of a Bezier path over time, make sure to create initial keyframes for all four path control
points; moving a control point without an initial keyframe doesn’t move it over time. You may find it easier to animate
a path by modifying the motion paths of individual control points in the Layer panel.
Note: Handles appear in the Composition panel only if the effect is selected in the Effect Controls panel and if you aren’t
animating text along a mask or path.
If you want to move a Bezier path across the composition, and you don’t want to change its shape, animate the layer
rather than the path. If you want to stretch, shrink, or wag one side of the Bezier path while keeping the other half in
the same position, move a tangent-vertex pair together. To do so, create keyframes for both by dragging the outer circle
of the appropriate vertex.
Note: When animating the control points of a Bezier path, don’t confuse the Bezier path shape with the Bezier spatial
interpolation of the keyframes. Like keyframes for other position controls, keyframes for the vertex or tangent of a Bezier
path can be set to either linear or Bezier. You specify default spatial interpolation in General Preferences. You can specify
spatial interpolation for individual keyframes by choosing Animation
> Keyframe Interpolation.
You can apply motion blur to motion that you create with the Path Text effect. Blurring occurs on each character. Like
motion blur for layers, blurring for characters is more visible when movement is quick. For example, blurring is
pronounced when you choose negative jitter values, which produce jumpy motion.
Path Options controls
Shape Type Defines the shape of the path. The Path Text effect name must be selected in the Effect Controls panel to
make the path visible in the Composition panel.
• Bezier Shapes text along a Bezier curve, defined by four control points (Vertex 1/Circle Center, Tangent 1/Circle
Point, Tangent 2, and Vertex 2). Characters that don’t fit on the path are placed off the end in a straight line.