HTML5 and Mobile Game Development - Learn HTML5 by Creating Fun Games - page 398

};
// This represents how much energy the entity
has left. When
// the energy gets to or below zero, the
entity dies
this.getEnergy = function() {
return energy;
};
// Update the entity's energy levels
this.takeDamage = function(damage) {
energy -= damage;
return energy;
};
};
The LaserGun component is slightly more involved because it contains a collection
of entities that it manages. Each time a laser beam is fired by the entity containing
the laser gun, a new entity is created to represent that laser beam. This entity is sim-
ilar to all the other entities in the game since it also contains a sprite component
to draw itself a Move component and a physics component as well.
Each time the laser gun updates itself, it needs to move all of its lasers forward
and remove any of its laser beams from its control if the laser has gone outside the
screen area.
var Packt = Packt || {};
Packt.Components = Packt.Components || {};
Packt.Components.LaserGun = function(entity,
canvas, maxShots) {
var entity = entity;
var MAX_SHOTS = maxShots;
var canvas = canvas;
var shots = new Array();
var shotsPerSec = 1000 / 15;