[JAVA][Beginning Java 8 Games Development]

Chapter 5 ■ An Introduction to Game Design: Concepts, Multimedia, and Using Scene Builder
Game Design Concepts: Sprites, Physics, Collision
Let’s take a look at the various game design components that we you will need to understand to be able to build a
game, as well as what Java 8 (or JavaFX) packages and classes you can use to implement these aspects of game play,
which I like to term components of game play. These can include the game play elements themselves (commonly
referred to as sprites) as well as processing engines, which you will either code yourself, or import preexisting Java
code libraries for, such as physics simulation and collision detection.
Sprites are the foundation of game play, defining your main character, projectiles used to damage this main
character, and the enemies firing these projectiles. Sprites are 2D graphics elements and can be either static (fixed,
a single image) or dynamic (animated, a seamless loop of several images). A sprite will be moved around the screen
based on programming logic, which dictates how the game is to function. Sprites need to be composited with
background imagery and other game elements as well as other sprites and so the graphics used to create the sprites
will need to support transparent backgrounds.
In Chapter 4, I introduced you to the concept of alpha channels and transparency. You will need to achieve this
same end result with your sprites to create a seamless visual experience with your game. The next most important
aspect of game play is collision detection, because if your sprites simply flew right past each other on the screen
and never did anything cool when they touched, or “intersected” each other, then you really would not have much
of a game! Once you add a collision detection engine (composed of intersection logic processing routines) your
game can ascertain when any two sprites are touching (edges) or overlapping each other. A collision detection will
call (trigger) other logic processing routines that will determine what happens when any two given sprites, such as
a projectile and the main character, intersect. For example, when a projectile intersects the main character, damage
points might accrue, life force index might be decreased, or a death animation may be started. In contrast, if a treasure
item intersects with (is picked up by) the main character, power or capability points might accrue, the life force index
might be increased, or an “I found it” jubilation animation might be started. As you can see, the collision detection for
your game is one of the foundational design elements of your game play, besides the sprites (characters, projectiles,
treasures, enemies, obstacles, and so on) themselves, which is why I am covering this concept early on in the book.
The concept next in significance to your game play is real-world physics simulation. The addition of things like
gravity; friction; bounce; drag; acceleration; motion curves, such as the JavaFX Interpolator class provides; and the like
add an additional level of realism on top of the already photo-realistic sprites, synchronized animation sequences,
scenic backgrounds, and highly accurate collision detection.
Finally, the most proprietary attribute, or logic construct (Java code), to add to your game play is the custom
game play logic, which makes your game truly unique in the marketplace. This logic should be kept in its own Java
class or methods, separate from physics simulation and collision detection code. After all, Java 8 makes your code
modularization well-structured if you learn the OOP concepts and apply them to your programming logic!
When you start to add all these game components together, they begin to make the game more believable as
well as more professional. One of the key objectives for a great game is suspension of belief, which means that your
player is buying into the premise, characters, objectives, and game play completely. This is the same objective that any
content producer, whether he or she be a filmmaker, television producer, author, songwriter, Java 8 game programmer,
or application developer, is going for. Games these days have the same revenue-generating capability as any of the
other content distribution genres, if not more.
Next, let’s take a look at the different types of games that can be created and how these differ in their application
of the core game components of sprites, collision detection, physics simulation, and game play logic.
Types of Games: Puzzles, Board Games, Arcade Games, Hybrids
Like everything else I have talked about in this chapter, games themselves can be categorized by using a
static-versus-dynamic classification approach. Static games are not processor bound, because they tend to be turn
based and not hand-eye coordination based in nature, and so, in a sense, they are easier to get working smoothly;
only the programming logic for the rules of game play and the attractive graphics have to be put in place and
104
www.it-ebooks.info