[JAVA][Beginning Java 8 Games Development]

Chapter 4 ■ An Introduction to JavaFX 8: Exploring the Capabilities of the Java 8 Multimedia Engine
The Scene class is used to create a Scene object, using the Scene() constructor class, which takes between one
and five parameters, depending on which of the six (overloaded) constructor methods you choose to use. These
include the following constructor methods, along with their six different (and thus overloaded) parameter list data
field configurations:
Scene(Parent root)
Scene(Parent root, double width, double height)
Scene(Parent root, double width, double height, boolean depthBuffer)
Scene(Parent root, double width, double height, boolean depthBuffer, SceneAntialiasing aAlias)
Scene(Parent root, double width, double height, Paint fill)
Scene(Parent root, Paint fill)
The constructor currently used in your bootstrap Java and JavaFX code is the second one, called as follows:
Scene scene = new Scene(root, 300, 250);
If you wanted to add a black background to the scene, you would select the fifth overloaded constructor method,
using a Color.BLACK constant from the Color class (this is a Paint object, because Color is a Paint subclass) as your
fill data (in this case, a fill Color). You would do this by using the following Scene() object constructor method call:
Scene scene = new Scene(root, 300, 250, Color.BLACK);
Note that the root object is a Parent subclass, called the StackPane class, created using the StackPane()
constructor method (two lines above the Scene() constructor method call) by using the following line of Java code:
StackPane root = new StackPane(); // StackPane subclassed from Parent, so Parent root satisfied
As you can see, any class can be used in the constructor that is a subclass of the object (class) type that is declared
(required) for that constructor parameter position (data). You are able to use Color and StackPane objects in your
parameter list because they have superclass origins from the Paint and Parent classes, respectively.
In case you are wondering, the Boolean depthBuffer parameter is used for 3D scene components. Because
these scene components are 3D and have depth (a z component, in addition to 2D x and y components), you will
need to include this parameter, and set it to a value of true, if you are creating 3D scenes or combining 2D and 3D
scene components. Finally, the SceneAntialiasing object (and class) that is passed in the parameter list for the fourth
constructor method provides real-time smoothing for 3D scene components.
JavaFX Scene Graph: Organizing Scenes, Using Parent Nodes
A scene graph, which is not unique to JavaFX and which can be seen in quite a few new media content creation
software packages, is a data structure that resembles an upside-down tree, with the root node at the top and branch
nodes and leaf nodes coming off the root node. The first time I saw a scene graph approach to design was when I was
3D modeling using a software package on the Amiga called Real 3D from Realsoft Oy. This approach has been copied
by many 3D, digital video, and digital imaging software packages since then and now is a part of how JavaFX organizes
content and scenes. For this reason, many of you may be familiar (and comfortable) with this design paradigm.
JavaFX Scene Graph data structure allows you not only to architect, organize, and design your JavaFX scene and
its content, but also to apply opacity, states, event handlers, transformations, and special effects to entire logical
branches of the Scene Graph hierarchy if you set up the Scene Graph correctly. Figure 4-3 shows the basic Scene
Graph tree, with the root node at the top and branch and leaf nodes below it.
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