[JAVA][Beginning Java 8 Games Development]

Chapter 9 ■ Controlling Your Action Figure: Implementing Java Event Handlers and Using Lambda Expressions
Figure 9-14. Add the case statements for ASDW keys to give users two key options, or to allow two-handed game play
This is in keeping with our objective of optimizing both memory and CPU cycles, so that these are available for
the more advanced parts of our game play, such as the game play logic, collision detection, or physics calculation.
We also added constants that will allow us to later scale this 640 by 400 game prototype to fit display screens of
different resolutions such as Pseudo HD (1280 by 720), True HD (1920 by 1080), and UHD (4096 by 2160). These can
also be used in the game logic, to calculate the size of the screen area to determine movement boundaries.
So far, we have added our actor and supporting cast engine, as well as our basic event handling processing, so
that we can start to determine how this InvinciBagel game hero is going to move around on the screen in the next
chapter. We have .handle() as well as .update() and .collide() methods in place to hold the code, which will animate a
character, and eventually enemies, in both the single-player as well as a future multi-player version of this game.
Next, let’s revisit our overview diagram of this game design, and take a look at the InvinciBagel package, the
InvinciBagel.java class, and the GamePlayLoop and Actor and Hero classes, which provide the foundation for our
game play processing and actor (and projectiles, treasure, enemy and obstacles or “props”) creation.
Updating Our Game Design: Adding Event Handling
Let’s update the diagram that I introduced in Chapter 7 (Figure 7-19) and updated in Chapter 8 (Figure 8-17) to
include the ActionEvent and KeyEvent handling by the EventHandler class. As you can see in Figure 9-15, I added
the EventHandler event handling class to the diagram as well as the ActionEvent objects that handle our UI design
control and the KeyEvent that we are going to use to move the InvinciBagel actor around the screen. Since the
.setOnKeyPressed() and .setOnKeyReleased() methods are called off of the scene Scene object named scene, and the
ActionEvent is also contained under the Scene object, I placed these inside of the Scene object in the diagram.
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