Arduino Uno Quick Start Manual page 135

First of all, it defines a constant named
number of lives in the game. This is the place to go for cheaters. The
map defines the game s possible states. This is a very common pattern in
game programming, and you ll see later how easy it is to write the game s
main loop when you identify the game states properly.
The Game object defines all of the game s properties, such as the current score,
the number of lives left, and the game s current state. It also contains all
information about the game s object, such as the ball s current velocity in all
directions or the paddle s speed. Of course, it also defines a
object, and you have to adjust the path to the Arduino s serial port.
Most of the Game
velocity in the X direction to a random value. This way, the ball won t always
go into the same direction each time you start a new round.
Note that we use jQuery functions for the first time when we determine the
width and height of the game objects. Look at the following piece of code:
width: $("#paddle").width()
It looks cryptic at first, but it should be obvious that it somehow determines
the paddle s width. Therefore, it uses jQuery s most important method. Its
name is $ (yes, you can actually define a JavaScript function named
it s a versatile method you can use for various purposes.
The $ function expects a single argument you can use to specify a certain
element in your current HTML page. To identify the element, you can use the
usual CSS selectors. In our case, we d like to get the element with the ID
paddle , and in CSS you can look up elements specified by an ID by inserting
the # character before the ID.
After we ve retrieved the element we re looking for, we use jQuery s
to read its width. jQuery offers many more methods for accessing all possible
CSS attributes. Using these methods for getting and setting CSS attributes
is much easier than using JavaScript s native functions for looking up and
manipulating elements on the current HTML page.
Now that we ve set up the game s data structures, we can implement the
game s main logic. We start by defining a few methods for initializing and
resetting the game.
BrowserGame/Arduinoid/js/arduinoid.js
function initGame() {
Line 1
Game.state = GameStates.PAUSED;
-
Game.lives = MAX_LIVES;
-
objects are constants at the beginning; we set only the ball s
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Creating the Game
MAX_LIVES that contains the maximum
117
GameStates
GameController
$ ), and
width method
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