FogOfWarViewer.js

  1. /* 
  2.  * To change this license header, choose License Headers in Project Properties.
  3.  * To change this template file, choose Tools | Templates
  4.  * and open the template in the editor.
  5.  */
  7. /*jslint node: true, vars: true */
  8. /*global gEngine, Scene, GameObjectset, TextureObject, Camera, vec2,
  9.   Renderable, FontRenderable, SpriteRenderable, LightRenderable,
  10.   GameObject, Hero, Minion, Dye, Light */
  11. /* find out more about jslint: http://www.jslint.com/help.html */
  13. "use strict";  // Operate in Strict mode such that variables must be declared before used!
  15. /**
  16.  * Subclass of FogOfWar. Object tracks the movement of target object and radius for Field of View.
  17.  * @name FogOfWarViewer
  18.  * @constructor
  19.  */
  20. function FogOfWarViewer(){
  21.     this.mTarget = null;
  22.     this.mXPos = null;
  23.     this.mYPos = null;
  24.     this.mChanged = true;
  25.     this.mRadius = null;
  26. }
  28. /**
  29.  * Sets the target and radius for an object to have a Field of View.
  30.  * @param {object} t - Already created object for the Fog Of War to track. 
  31.  * @param {number} r - radius in World Coordinates
  32.  */
  33. FogOfWarViewer.prototype.setTarget = function(t, r) {
  34.     this.mTarget = t;
  35.     this.mXPos = t.getXform().getXPos();
  36.     this.mYPos = t.getXform().getYPos();
  37.     this.mRadius = r;
  38. };
  40. /**
  41.  * Removes the target object from FogOfWarViewer object. 
  42.  */
  43. FogOfWarViewer.prototype.removeTarget = function () {
  44.     this.mTarget = null;
  45.     this.mXPos = null;
  46.     this.mYPos = null;
  47.     this.mRadius = null;
  48. };
  50. /**
  51.  * Checks to see if the target object has changed positions. 
  52.  * @returns {Boolean} - true if target object has changed X or Y location in World Coordinates.
  53.  */
  54. FogOfWarViewer.prototype.checkMove = function(){
  55.     var targetX = this.mTarget.getXform();
  56.     if(!this.mChanged){
  57.         if(targetX.getXPos() === this.mXPos && targetX.getYPos() === this.mYPos){
  58.             return false;
  59.         }else{
  60.             return true;
  61.         }
  62.     }else{
  63.         this.mChanged = false;
  64.         return true;
  65.     }
  66. };
  68. /**
  69.  * Changes the size of radius for a Field of View.
  70.  * @param {number} r - New radius in World Coordinates.
  71.  */
  72. FogOfWarViewer.prototype.setRadius = function (r){
  73.     this.mRadius = r;
  74.     this.mChanged = true;
  75. };
  77. /**
  78.  * Returns the value of radius for Field of View for this object. 
  79.  * @returns {Number} - Radius in World Coordinates.
  80.  */
  81. FogOfWarViewer.prototype.getRadius = function (){
  82.     return this.mRadius;
  83. };
  85. /**
  86.  * Returns the X location in World Coordinates. 
  87.  * @returns {Number} - X location in World Coordinates.
  88.  */
  89. FogOfWarViewer.prototype.getX = function(){ return this.mXPos; };
  91. /**
  92.  * Returns the Y location in World Coordinates. 
  93.  * @returns {Number} - Y location in World Coordinates.
  94.  */
  95. FogOfWarViewer.prototype.getY = function(){ return this.mYPos; };
  97. /**
  98.  * Returns the target object. 
  99.  * @returns {Object} - Target object for this FogOfWarViewer.
  100.  */
  101. FogOfWarViewer.prototype.getTarget = function () { return this.mTarget; };
  103. /**
  104.  * Updates the previous X and Y location.
  105.  */
  106. FogOfWarViewer.prototype.update = function (){
  107.     if(this.mTarget !== null){
  108.         this.mXPos = this.mTarget.getXform().getXPos();
  109.         this.mYPos = this.mTarget.getXform().getYPos();
  110.     }
  111. };