[JAVA][Beginning Java 8 Games Development]

Chapter 6 ■ The Foundation of Game Design: The JavaFX Scene Graph and the InvinciBagel Game Infrastructure
Game Design Foundation: Primary Function Screens
One of the first things you want to design is the top-level, or highest-level, UIs that your game’s users will interface
with. These will all be accessed using the InvinciBagel splash (branding) screen, contained in the primary
InvinciBagel.java class code. As discussed previously, this Java code will extend the javafx.application.Application
class and will launch the application, displaying its splash screen, along with options to review instructions, play the
game, see the high scores, or review the game’s legal disclaimers and game creator credits (programmer, artist, writer,
composer, sound designer, and so on). A high-level diagram showing the game, starting with functional UI screens at
the top and progressing down to the OS level, can be seen in Figure 6-1.
Figure 6-1. Primary game functional screens and how they are implemented through Java and JavaFX API, using a JVM
This will require adding three more Button nodes to your StackPane layout container Parent node as well as
an ImageView node for the splash screen background image container. The ImageView node will have to be added
to the StackPane first to be the first child node in the StackPane (z-order = 0), as this ImageView holds what I call
the background plate for the splash screen UI design. Because it is in the background, the image would need to be
behind the Button UI control elements, which will have z-order values of 1 through 4.
This means that you will be using six Node objects (one parent node and five child nodes) in your application’s
scene graph just to create your InvinciBagel splash screen! The instructions and credit screens will use another
ImageView node, so you are up to six nodes already, and the high scores screen will likely use another two
(ImageView and TableView) nodes, so you likely have more than eight nodes in the Scene Graph for creating the game
support infrastructure before you have even considered adding the nodes for the game play screen, which is,
of course, where you want to get the best performance possible for your game.
This really is not so bad if you think about it, as these screens are all static and do not need to be updated, that
is, the (UI) elements they contain are fixed and do not require updates using the pulse system, and so you should
essentially still have 99 percent of the power of the JavaFX pulse engine left over to process an InvinciBagel game
GamePlayLoop engine. In fact, as Java 8 and JavaFX 8 continue to improve the efficiency of their platform APIs and
classes, you may actually have even more processing power left over for game play (sprite movements, collisions,
physics, animation, and so on) and thus will be in good shape.
The GamePlayLoop will process the game code for you, using the javafx.animation package and its
AnimationTimer class. You will always need to be cognizant of how many Scene Graph Node objects you are asking
the pulse engine to process, because, if this number gets to be too large, it will start to affect the game’s performance.
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