feed-the-triangles.js

// This is an example of JS prototypes in a simple,
// incomplete game about keeping pet triangles.
 
// Triangles are rats.
// They go beep and trundle (among other things).
// Just roll with it.
 
// Here's our prototype for a standard triangle!
// As you can see, they each have a name,
// make beeping sounds when poked, trundle around,
// and can interact with food or take naps when they've
// eaten too much.
 
function Triangle(name) {
  this.name = name;
  this.sound = "beep"; // Default beeping sound.
  this.speed = 1; // Default triangle speed.
  this.trundle = function() {
    // Allows triangle to move.
  }
  this.poke = function() {
    // Plays beeping sound when triangle is clicked.
  }
  this.naptime = function() {
    // Checks if triangle has eaten too much lately.
    // If so, moves triangle to back corner &
    // drops speed to 0 for 20 ticks.
  }
  this.getFood = function() {
    // Checks if triangle is hungry.
    // If so, triangle will eat.
    // If not, triangle will pick up nearest food
    // & put it in a pile in the corner.
  }
}
 
 
// Just DRYing this code off a little over here.
 
function randomInt(min, max) {
  return Math.floor(Math.random() * (max - min + 1)) + min;
}
function randomCoord(size) {
  return randomInt(0, size - 1);
}
 
 
// This game randomizes the size of the triangle cage,
// showing the versatility of constructor functions.
// When the triangle keeper scatters food in the cage,
// it has to stay within the bounds of the cage, so all
// coordinates are calculated from the initial size of
// the instantiated triangle cage.
 
// This allows us to make any number of cages without
// being clumsy and scattering food outside the cage. :) 
 
function Cage() {
  this.size = randomInt(5,10); // Size between 5-10 sq. units.
  
  // Initializes array for foods.
  this.foods = new Array(this.size);
  for (i = 0; i < this.size; i++) {
    this.foods[i] = new Array (this.size);
  }
  
  // Scatters food inside the cage.
  this.scatterFood = function() {
    for (i = 1; i < (this.size * 3); i++) {
      var x = randomCoord(this.size);
      var y = randomCoord(this.size);
      if (this.foods[x][y] = null) {
        this.foods[x][y] = 1;
      } else {
        this.foods[x][y] += 1;
      }
    }
  }
}
 
// So let's start our game...
 
function newGame() {
  
  // We start by giving the triangles a house to live in.
  var triangleHouse = new Cage();
  
  // Once the triangles have a house, we need to allow any
  // new triangles to have coordinates within the bounds of that
  // cage, so we modify the prototype based on the cage size.
  Triangle.prototype.position = function() {
  return [randomCoord(triangleHouse.size), randomCoord(triangleHouse.size)];
  }
  
  // Then we scatter some food in the new cage,
  // and we put the triangles in it!
  triangleHouse.scatterFood();
  var lumi = new Triangle("Lumi");
  var eowyn = new Triangle("Eowyn");
}
 
// Since this is just an example of how useful
// prototypes are, this game is VERY incomplete.
 
// I hope you enjoyed reading it!  <:3   )~~~~