Game Development Reference
Open the Motion Tile.aep project from the Chapter 17 folder
of the exercise fi les. This simple project contains one comp with
a tank I created in Illustrator. Apply the Motion Tile effect to this
tank (Fig. 17.46 ).
Figure 17.46 The Motion Tile.
The Tile Center property at the top of the effect in the Effect
Control panel is akin to the offset value. Taking the X dimension
of the Tile Center value to 650 shows how this effect functions
like the Offset effect. It allows you to create an apparently endless
loop of your layer. If we animated this property high enough, we
would create a large armada of tanks traveling in one direction
(Fig. 17.47 ).
The values of Tile Width and Tile Height are a little mislead-
ing, but they're also two of the more powerful properties in this
effect. Think of these two as scale values. And, with an effect like
Motion Tile that repeats elements, making something appear
smaller—in either dimension—will create more copies. Take both
the Tile Width and Tile Height values to 20. This scales down the
tanks and creates many more of them. Because both these val-
ues are the same, the tank scales down proportionately. If they
were different, we would have a nonuniform scale of our object
(Fig. 17.48 ).
The Output Width and Output Height values are essentially
horizontal and vertical masks for this effect. If I reduce the
Output Width value to 60, for example, then the left and right
sides are cropped. This is similar to duplicating the layer and
applying a mask to it, but it saves you a step. Let's say that you