(function( $ ){

$.Point = function( x, y ) {
    this.x = typeof ( x ) == "number" ? x : 0;
    this.y = typeof ( y ) == "number" ? y : 0;
};

$.Point.prototype = {

    plus: function( point ) {
        return new $.Point(
            this.x + point.x, 
            this.y + point.y
        );
    },

    minus: function( point ) {
        return new $.Point(
            this.x - point.x, 
            this.y - point.y
        );
    },

    times: function( factor ) {
        return new $.Point(
            this.x * factor, 
            this.y * factor
        );
    },

    divide: function( factor ) {
        return new $.Point(
            this.x / factor, 
            this.y / factor
        );
    },

    negate: function() {
        return new $.Point( -this.x, -this.y );
    },

    distanceTo: function( point ) {
        return Math.sqrt(
            Math.pow( this.x - point.x, 2 ) +
            Math.pow( this.y - point.y, 2 )
        );
    },

    apply: function( func ) {
        return new $.Point( func( this.x ), func( this.y ) );
    },

    equals: function( point ) {
        return ( 
            point instanceof $.Point 
        ) && ( 
            this.x === point.x 
        ) && ( 
            this.y === point.y 
        );
    },

    toString: function() {
        return "(" + this.x + "," + this.y + ")";
    }
};

}( OpenSeadragon ));