Taking Our Game to the Next Level - jMonkeyEngine 3.0 - page 498

How to do it...
First of all, we need some basics set up.
1. We create a new application extending SimpleApplication , and add an Au-
dioNode field called audioNode .
2. In addition to this, we need to keep track of passed time with a float field called
time and another float field called pauseTime , which we set to 0.7f .
3. In the simpleInitApp method, we create a new audioNode instance:
new AudioNode(assetManager, "Sound/Effects/Foot
steps.ogg");
4. We override the simpleUpdate method and begin by checking whether time is
more than pauseTime .
5. If it is, we should set a new float called pitch . This should have a value of 1f
+- 10% , which can be achieved with the following code:
FastMath.nextRandomFloat() * 0.2f + 0.9f.
6. Then, we call audioNode.setPitch(pitch) to set it.
7. Since this particular sound file plays four footsteps in sequence, we tell the node to
not start from the beginning and only play the last of the footsteps by skipping for-
ward in time, using the following code:
audioNode.setTimeOffset(2.0f);
audioNode.playInstance();
8. Before exiting the if statement, we set time to 0 .
9. Finally, we shouldn't forget to increase time by tpf.
10. Try running the application now. We should hear the same sound over and over
again but with a slight variation.
11. We can use LowPassFilter to further vary the sound. We instantiate it by sup-
plying a float for the general volume, and another for the high frequency volume.
To get the most variation, we can supply two random values between 0f and 1f:
LowPassFilter filter = new
LowPassFilter(FastMath.nextRandomFloat(),
FastMath.nextRandomFloat());