iPhone Game Development

Animation

Our game will contain a main character and several animated animals. Each of these entities will require one or more animations for each of their behaviors and each of the directions they could be facing during those behaviors. For instance, the main character could have “idle,” “walking,” and “jumping” animations in the “north,” “south,” “east,” and “west” directions.

Once our artist has rendered each of these, we can assemble them together into a sprite texture similar to the unique tile strip texture we will use for the tile engine map. However, these animations are much more complex than the unique tile strip. See Figure 4-3, for instance, for the images we need to represent a walking emu chick.

Figure 4-3. Emu chick walking animation

As you can see, the emu chick sprite texture has three animations: walking west, walking north, and walking south (we omitted walking east because it can be created by flipping the walking west animation horizontally, which saves precious texture memory).

To make things more complicated, the animations are set up in such a way that some frames should be used multiple times in a single animation sequence. Specifically, the walking west animation should be displayed in the frame sequence 0, 1, 2, 3, 4. If we had a more complex animation, this format would support something similar to 0, 1, 0, 2, 0, 3…, where the frame indexes are not sequential. ...