Technical data

82 Preparing Web Graphics
As you switch between frames, you are switching between states of the
image. In the simple example above, the six frames define six states in
terms of Property 1—each of the six frames defines a different layer as
“shown.” We could rearrange the stacking order of the layers, or
rename them—and the animation itself wouldn’t change.
Thus, when you create a new frame on the Animation tab, you’re not
adding a new layer. The new frame merely enables you to define a new
state of the layers that already exist. Of course, you could go on and
create an additional layer, but then all your frames would need to take
that layer into account—in other words, hide it when it wasn’t needed.
HANDS ON: Follow the Bouncing Ball
To demonstrate single-layer animation, let’s create an example with a
bouncing ball—created with four frames but on just one layer. In this
animation, the four frames will define four states in terms of Property
2—the position of the layer contents.
q Close the Swirl animation window (we’re done with it). To begin
creating a new animation, choose New… from the File menu. If
the Startup Wizard is enabled, click on Create an Animation to
open the New Image dialog. You’ll notice that the Animation
option box is checked.
q Specify dimensions (100x100 is fine), set the Background to
“Transparent,” and click OK.
A new, untitled image window will open, and the Animation tab will
now look something like this:
q For this project, make sure the Endless Loop button is down.