[JAVA][Beginning Java 8 Games Development]

Chapter 17 ■ Enhancing Game Play: Creating a Scoring Engine, Adding Treasure and an Enemy Auto-Attack Engine
Figure 17-29. Add integer variables at the top of the Enemy.java class; set attackCounter=0, and attackFrequency=250
Now we are ready to start to put a half dozen fairly complicated methods into place in the Enemy.java class.
These will use the GamePlayLoop class’s .handle() method, to tap into the JavaFX 60 FPS pulse timing event engine,
to drive a fully automated, fully randomized Enemy attack. The code that we’ll be putting together during the
remainder of this chapter is the equivalent of turning the computer processor into our game player’s opponent. Let’s
write code!
The Foundation of an Enemy Class Attack: The .update() Method
Let’s start by writing the foundation of our iBeagle Enemy auto-attack engine. The first thing that we want to do
is to “throttle” the 60 FPS pulse engine, and make sure that attacks only happen every four seconds. This is done
using the attackCounter and attackFrequency variables inside of an if() structure, which counts between the two
variables. If the attackCounter reaches 250, it is reset to 0 and an initiateAttack() method is called. Otherwise (else)
the attackCounter is incremented using +=1. You could also use attackCounter++ to accomplish this. The code for
the basic conditional if() structure, which can be seen highlighted in the middle of Figure 17-30, should look like the
following Java method:
public void update() {
if(attackCounter >= attackFrequency) {
attackCounter=0;
initiateAttack();
} else {
attackCounter+=1;
}
}
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