[JAVA][Beginning Java 8 Games Development]

Chapter 16 ■ Collision Detection: Creating SVG Polygons for the Game Actors and Writing Code to Detect Collision
Figure 16-29. Remove the iBagel object from the front of the list of objects passed into the .addCurrentCast() method
Now we are ready to start to put the methods into place in the Bagel.java class that will check the iBagel object
for collision against the objects which are in the CURRENT_CAST List object by checking the boundaries for
each object’s Node (ImageView), and collision Shape (SVGPath). What we will be covering next can get somewhat
complicated, but if you want to really create a legitimate game title, you need to be able to know when the game play
elements intersect (called collide in game development terminology) with each other. Let’s dive into that Abyss now!
Bagel Class Collision Detection: .checkCollision( )
Right-click on the Bagel.java class in the Projects pane shown in Figure 16-29 and select the Open option and open up
the Bagel.java tab in NetBeans 8. Go into the .update() method, and comment out the playAudioClip() method call,
using two forward slashes at the beginning of the line of code. This will effectively turn off the audio for the KeyEvent
(KeyCode) KeyPressed constant call-outs that we have in place. The reason I am doing this is because I am going to
use this audio to “call out” a detected collision in the code that we’re about to create. Next, create a .checkCollision()
method call at the end of the methods that are called inside of the .update() method. This method will call collision
detection Java code, which we are about to put into place during the remainder of this chapter, on every pulse event
that is processed. This is in keeping with the logical sequence of game code processing inside of the .update() method.
The new .update() method, which is seen in Figure 16-30, should look like the following Java method body:
public void update() {
setXYLocation();
setBoundaries();
setImageState();
moveInvinciBagel();
// playAudioClip();
checkCollision();
}
370
www.it-ebooks.info