[JAVA][Beginning Java 8 Games Development]

Chapter 11 ■ Moving Your Action Figure in 2D: Controlling the X and Y Display Screen Coordinates
As you can see in Figure 11-6, the code is error-free, and you now have an iBagel Bagel object that you can now
use to start to develop the InvinciBagel sprite movement around the game play stage, which is usually the entire
display screen. We’ll be wiring this Bagel Actor up to the JavaFX pulse timing engine a bit later on during this chapter.
Figure 11-6. Add a private void createGameActors() method; add an iBagel object instantiation via Bagel() constructor
In case you’re wondering what the SVGdata String object “M150 0 L75 200 L225 200 Z” does, it is shorthand for
the following line drawing instructions (commands). The M is a “Move Absolute” command and tells the line draw
(or in this case a path draw) operation to start at location 150,0. The L is a “Line Draw To” command and tells the SVG
data to draw a line from 150,0 to 75,200. The second L draws a line from 75,200 to 225,200, giving us two sides of the
triangle shape. The Z is a “Close Shape” command, which, if the shape is open, as ours is currently, will draw a line
to close the shape. In this case, that would equate to drawing a line from 225,200 to 150,0, giving us three sides to our
triangle shape, closing the open path, and giving us a valid collision detection boundary.
We will be replacing this with a more complex collision shape later on, during Chapter 16 covering collision
detection polygon creation, SVG data, and collision detection logic. Our actual collision polygon will contain many
more numbers, making our Bagel() constructor method call unwieldy. As you might imagine, at that point in the game
(no pun intended), I will probably create a work process that will be used specifically for constructing collision shapes.
This work process will show you how to generate SVG polygon data using GIMP so that you can place SVG data into
its own String object, and reference that in your Actor object constructor. If you wanted to turn collision data creation
into its own method as well, this is how that would look, using a (theoretical) .createActorCollisionData() method:
String cBagel; // Create String variable named cBagel (collision data Bagel) at top of class
private void createActorCollisionData() {
cBagel = "M150 0 L75 500 L225 200 Z";
}
private void createGameActors() {
iBagel = new Bagel(cBagel, 0, 0, iB0,iB1,iB2,iB3,iB4,iB5,iB6,iB7,iB8);
}
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