[JAVA][Beginning Java 8 Games Development]

Chapter 8 ■ Creating Your Actor Engine: Design the Characters for Your Game and Define Their Capabilities
Figure 8-6. Add an Arrays import statement to support constructor method; add a public abstract .update() method
Next, we will add the rest of the attributes (or variables) for our fixed sprite Actor superclass, which requires us to
think ahead, regarding what we want to be able to accomplish with our sprites during the creation of this game.
Adding Sprite Control and Definition Variables to an Actor Class
The next part of the process is easy, from a coding standpoint, as we will be declaring some more variables at the top
of the Actor class. From a design standpoint, this is more difficult, however, as it requires that we think ahead as far as
possible, and speculate about what variable data we will need for our sprite actors, both fixed and motion sprites, to
be able to do everything that we want to during the construction of this game, as well as during its game play.
The first additional variables I am going to declare after the iX and iY variables are the pX and pY pivot point
variables. I had originally placed these in the Hero subclass, which we’re going to create next, once we are done with
the creation of this Actor superclass. The reason I moved these “up” to the Actor superclass level is because I wanted
to have the flexibility of rotating fixed sprites (treasure and obstacles) as well as motion sprites. This gives me more
power and flexibility where level and scene design purposes are concerned. These pivot point X and Y variables would
be declared as protected double data variables, and would be done using the following two lines of Java code:
protected double pX;
protected double pY;
Next, we need to add some boolean “flags” to our Actor class (object) definition. These will indicate certain
things about the sprite object in question, such as if it is Alive (for fixed sprites this will always be false) or Dead, or
if it is Fixed (for fixed sprites this will always be true, and true for motion sprites that are not in motion) or Moving,
or Bonus objects, indicating additional points (or lifespan) for their capture (collision), or Valuable, indicating
additional powers (or lifespan) for their acquisition (collision). Finally, I’m defining a Flip Horizontal and Flip
Vertical flag, to give me four times the flexibility with (fixed or motion) sprite image assets than I would have without
these flags in place.
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