/**********************************************************
 Very minorly modified from the example by Tim Taylor
 http://tool-man.org/examples/sorting.html
 
 Added Coordinate.prototype.inside( northwest, southeast );
 
 **********************************************************/
var Coordinates = {
ORIGIN : new Coordinate(0, 0),
northwestPosition : function(element) {
var x = parseInt(element.style.left);
var y = parseInt(element.style.top);
return new Coordinate(isNaN(x) ? 0 : x, isNaN(y) ? 0 : y);
},
southeastPosition : function(element) {
return Coordinates.northwestPosition(element).plus(
new Coordinate(element.offsetWidth, element.offsetHeight));
},
northwestOffset : function(element, isRecursive) {
var offset = new Coordinate(element.offsetLeft, element.offsetTop);
if (!isRecursive) return offset;
var parent = element.offsetParent;
while (parent) {
offset = offset.plus(
new Coordinate(parent.offsetLeft, parent.offsetTop));
parent = parent.offsetParent;
}
return offset;
},
southeastOffset : function(element, isRecursive) {
return Coordinates.northwestOffset(element, isRecursive).plus(
new Coordinate(element.offsetWidth, element.offsetHeight));
},
fixEvent : function(event) {
if (typeof event == 'undefined') {
    		event = window.event;
}
    		
event.windowCoordinate = new Coordinate(event.clientX, event.clientY);
return event;
}
};
function Coordinate(x, y) {
this.x = x;
this.y = y;
}
Coordinate.prototype.toString = function() {
return "(" + this.x + "," + this.y + ")";
}
Coordinate.prototype.plus = function(that) {
return new Coordinate(this.x + that.x, this.y + that.y);
}
Coordinate.prototype.minus = function(that) {
return new Coordinate(this.x - that.x, this.y - that.y);
}
Coordinate.prototype.distance = function(that) {
var deltaX = this.x - that.x;
var deltaY = this.y - that.y;
return Math.sqrt(Math.pow(deltaX, 2) + Math.pow(deltaY, 2));
}
Coordinate.prototype.max = function(that) {
var x = Math.max(this.x, that.x);
var y = Math.max(this.y, that.y);
return new Coordinate(x, y);
}
Coordinate.prototype.constrain = function(min, max) {
if (min.x > max.x || min.y > max.y) return this;
var x = this.x;
var y = this.y;
if (min.x != null) x = Math.max(x, min.x);
if (max.x != null) x = Math.min(x, max.x);
if (min.y != null) y = Math.max(y, min.y);
if (max.y != null) y = Math.min(y, max.y);
return new Coordinate(x, y);
}
Coordinate.prototype.reposition = function(element) {
element.style["top"] = this.y + "px";
element.style["left"] = this.x + "px";
}
Coordinate.prototype.equals = function(that) {
if (this == that) return true;
if (!that || that == null) return false;
return this.x == that.x && this.y == that.y;
}
// returns true of this point is inside specified box
Coordinate.prototype.inside = function(northwest, southeast) {
if ((this.x >= northwest.x) && (this.x <= southeast.x) &&
(this.y >= northwest.y) && (this.y <= southeast.y)) {
return true;
}
else {
return false;
}
}
Coordinate.prototype.insideObject = function(obj, recurse) {
var nwOffset = Coordinates.northwestOffset(obj, recurse);
var seOffset = nwOffset.plus(new Coordinate(obj.offsetWidth, obj.offsetHeight));
var rt = null
if (this.inside(nwOffset, seOffset)) {
rt = this.minus(nwOffset);
rt.nwOffset = nwOffset;
rt.seOffset = seOffset;
}
return rt;
}
// getMousePos(event) has been depricated.  Use mousePos.update(event) instead.
function getMousePos(event) {
    mousePos.update(event);
}
function MousePos () { };
// Extend the "Coordinate" class
MousePos.prototype = new Coordinate(0, 0);
MousePos.prototype.update = function(event) {
event = Coordinates.fixEvent(event);
var position = event.windowCoordinate;
this.x = position.x;
this.y = position.y;
if (is_safari) {
// do nothing
}
else  {
this.x += document.body.scrollLeft;
this.y += document.body.scrollTop;
}
if (this.x < 0)
this.x = 0;
if (this.y < 0)
this.y = 0;
return event;
}
// Track mouse's absolute position (counting scrollbars)
var mousePos = new MousePos(0,0);