extlib/leaflet/src/core/Util.js

   1 /*
   2  * L.Util is a namespace for various utility functions.
   3  */
   4
   5 L.Util = {
   6         extend: function(/*Object*/ dest) /*-> Object*/ {       // merge src properties into dest
   7                 var sources = Array.prototype.slice.call(arguments, 1);
   8                 for (var j = 0, len = sources.length, src; j < len; j++) {
   9                         src = sources[j] || {};
  10                         for (var i in src) {
  11                                 if (src.hasOwnProperty(i)) {
  12                                         dest[i] = src[i];
  13                                 }
  14                         }
  15                 }
  16                 return dest;
  17         },
  18
  19         bind: function(/*Function*/ fn, /*Object*/ obj) /*-> Object*/ {
  20                 return function() {
  21                         return fn.apply(obj, arguments);
  22                 };
  23         },
  24
  25         stamp: (function() {
  26                 var lastId = 0, key = '_leaflet_id';
  27                 return function(/*Object*/ obj) {
  28                         obj[key] = obj[key] || ++lastId;
  29                         return obj[key];
  30                 };
  31         })(),
  32
  33         requestAnimFrame: (function() {
  34                 function timeoutDefer(callback) {
  35                         window.setTimeout(callback, 1000 / 60);
  36                 }
  37
  38                 var requestFn = window.requestAnimationFrame ||
  39                         window.webkitRequestAnimationFrame ||
  40                         window.mozRequestAnimationFrame ||
  41                         window.oRequestAnimationFrame ||
  42                         window.msRequestAnimationFrame ||
  43                         timeoutDefer;
  44
  45                 return function(callback, context, immediate) {
  46                         callback = context ? L.Util.bind(callback, context) : context;
  47                         if (immediate && requestFn === timeoutDefer) {
  48                                 callback();
  49                         } else {
  50                                 requestFn(callback);
  51                         }
  52                 };
  53         })(),
  54
  55         limitExecByInterval: function(fn, time, context) {
  56                 var lock, execOnUnlock, args;
  57                 function exec(){
  58                         lock = false;
  59                         if (execOnUnlock) {
  60                                 args.callee.apply(context, args);
  61                                 execOnUnlock = false;
  62                         }
  63                 }
  64                 return function() {
  65                         args = arguments;
  66                         if (!lock) {
  67                                 lock = true;
  68                                 setTimeout(exec, time);
  69                                 fn.apply(context, args);
  70                         } else {
  71                                 execOnUnlock = true;
  72                         }
  73                 };
  74         },
  75
  76         falseFn: function() { return false; },
  77
  78         formatNum: function(num, digits) {
  79                 var pow = Math.pow(10, digits || 5);
  80                 return Math.round(num * pow) / pow;
  81         },
  82
  83         setOptions: function(obj, options) {
  84                 obj.options = L.Util.extend({}, obj.options, options);
  85         },
  86
  87         getParamString: function(obj) {
  88                 var params = [];
  89                 for (var i in obj) {
  90                         if (obj.hasOwnProperty(i)) {
  91                                 params.push(i + '=' + obj[i]);
  92                         }
  93                 }
  94                 return '?' + params.join('&');
  95         }
  96 };