function blurInput(obj) {
  if (obj.value == "") obj.value = obj.defaultValue;
}
function focusInput(obj) {
  if (obj.value == obj.defaultValue) obj.value = "";
}
function preload(url) {
  var img = new Image();
  img.src = url;
}
function getBestStyle(obj) {
  if (window.getComputedStyle != undefined) {
    return window.getComputedStyle(obj);
  }
  else if (obj.currentStyle != undefined) {
    return obj.currentStyle;
  }
  else return obj.style;
}
function getPixels(s) {
  if (s == undefined || s.indexOf("px") == -1) {
    return 0;
  }
  else return parseInt(s.replace("px", ""));
}
function parseColor(s) {
  var a = Array();
  for (var i = 0; i < s.length; i += 2) {
    var b = s.substring(i, i + 2);
    a.push(parseInt(b, 16));
  }
  return a;
}

function colorString(a) {
  var s = "";
  for (var i = 0; i < a.length; i++) {
    var b = a[i].toString(16);
    if (b.length == 1) b = "0" + b;
    s += b;
  }
  return s.toUpperCase();
}

function interColor(a, b, p) {
  a = parseColor(a);
  b = parseColor(b);
  c = Array();
  for (var i = 0; i < a.length; i++) {
    var x = b[i] - a[i];
    x *= p;
    x += a[i];
    x = Math.round(x);
    c.push(x);
  }
  return colorString(c);
}
function setOpacity(obj, value) {
  obj.style.opacity = value;
  obj.style.filter = 'alpha(opacity=' + value * 100.0 + ')';
}
function getOffset(obj) {
  var x = 0;
  var y = 0;
  while (obj) {
    x += obj.offsetLeft || 0;
    y += obj.offsetTop || 0;
    obj = obj.offsetParent;
  }
  return {left: x, top: y};
}
function findChildByClass(obj, cname) {
  for (var i = 0; i < obj.childNodes.length; i++) {
    if (obj.childNodes[i].className == cname) {
      return obj.childNodes[i];
    }
  }
  return undefined;
}
function childrenWithClass(parent, className) {
  var items = Array();
  var children = parent.childNodes;
  for (var i = 0; i < children.length; i++) {
    var classes = children[i].className != undefined ? children[i].className.split(" ") : Array();
    for (var j = 0; j < classes.length; j++) {
      if (classes[j].toLowerCase() == className.toLowerCase()) {
        items.push(children[i]);
        break;
      }
    }
  }
  return items;
}
function getMovement(time, speed) {
  var px = Math.round(speed * time / 1000.0);
  if (speed < 0) {
    if (px >= 0) px = -1;
  }
  else {
    if (px <= 0) px = 1;
  }
  return px;
}
function onWindowLoad(handler) {
  if (window.addEventListener) {
    window.addEventListener("load", handler, false);
  }
  else if (window.attachEvent) {
    window.attachEvent("onload", handler);
  }
}

// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

// requestAnimationFrame polyfill by Erik Möller
// fixes from Paul Irish and Tino Zijdel
(function () {
  var lastTime = 0;
  var vendors = ['ms', 'moz', 'webkit', 'o'];
  for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
    window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
    window.cancelAnimationFrame = window[vendors[x] + 'CancelAnimationFrame']
    || window[vendors[x] + 'CancelRequestAnimationFrame'];
  }

  if (!window.requestAnimationFrame)
    window.requestAnimationFrame = function (callback, element) {
      var currTime = new Date().getTime();
      var timeToCall = Math.max(0, 16 - (currTime - lastTime));
      var id = window.setTimeout(function () {
          callback(currTime + timeToCall);
        },
        timeToCall);
      lastTime = currTime + timeToCall;
      return id;
    };

  if (!window.cancelAnimationFrame)
    window.cancelAnimationFrame = function (id) {
      clearTimeout(id);
    };
}());