Fixed #2 and #4

lib/math.js

@@ -234,6 +234,14 @@ Cannon.Math.Vector2D = Cannon.ClassFactory.extend({
 		return new Cannon.Math.Vector2D(this.x-v2.x, this.y-v2.y);
 	},
 	/**
+	Determines whether two vectors are equal
+	@param (Vector2D) toCompare
+	@type Boolean
+	*/
+	equals: function(toCompare){
+		return (this.x == toCompare.x && this.y == toCompare.y);
+	},
+	/**
 	Returns the right normal of the current vector
 	@type Vector2D
 	@return A new vector
@@ -243,6 +251,15 @@ Cannon.Math.Vector2D = Cannon.ClassFactory.extend({
 		return new Cannon.Math.Vector2D( this.y * -1, this.x);
 	},
 	/**
+	Returns the left normal of the current vector
+	@type Vector2D
+	@return A new vector
+	*/
+	leftNormal: function()
+	{
+		return new Cannon.Math.Vector2D( this.y, this.x * -1);
+	},
+	/**
 	Returns a bector representing the direction of the current vector
 	@type Vector2D
 	@return A new vector