Audio and Labels - Learn SpriteBuilder for iOS Game Development - page 370

other two close to when the Play and Settings buttons start to appear. Refer to Figure 11-4
for the final result.
To actually have the keyframes play back a sound effect, you have to double-click each
one to edit the keyframe's properties. The popover menu is shown in Figure 11-3 . From
the popover menu, select an audio file. The leftmost keyframe should use the Audio/
splat2.wav file, while the other two keyframes should use Audio/splat3.wav .
Figure 11-3 . Assigning an audio file to a Sound effects keyframe
Feel free to play with the Pitch , Pan , and Gain settings. A pitch of 1.0 means the audio
file will be played back at its original pitch (frequency). Choose a value between 0.01 and
1.0 to lower the sound's pitch, which will also increase its duration. Use a value above 1.0
to increase the pitch and shorten its duration. A pitch of 2.0 will play back the effect at
twice its original speed.
Pan is in the range of -1.0 and 1.0, where -1.0 plays the sound effect entirely on the left
speaker and 1.0 plays it only on the right speaker. The default panning value of 0.0 plays
the sound equally on both speakers. Panning has no effect on stereo files; only mono au-
dio files can be panned.
The Gain setting increases the sound's volume. It's not quite the same as volume though.
If you increase Gain by too much, it will add distortion to the sound. But, generally, it can
be used to level out some sounds that would otherwise be 10 to 20% quieter or louder than
other sounds. A value of 1.0 means the volume is unchanged. Lower values reduce the
volume, while higher values increase it.
Once you've moved the keyframes to the desired locations and assigned the audio files,
the result will resemble Figure 11-4 . Notice that the audio file waveforms may run past
the end of the Timeline, indicating that the audio plays longer than the Timeline. Whether
this is or isn't a problem depends on the situation. Here it doesn't matter.