update rect

lib/rect.js

@@ -1,52 +1,38 @@
-/* 
-Written by: Mark Busenitz, [email protected]
-*/ 
+'use strict';
 
-(function(){
+(function(exports){
 
-  function Rect( p, d ) {
-
-    if (typeof p !== 'undefined') {
-      this.left = p.x;
-      this.top = p.y;
-    }
-    else {
-      this.left = 0;
-      this.top = 0;
-    }
+  class Rect {
 
-    if (typeof d !== 'undefined') {
-      this.right = this.left + Math.abs( d.x );
-      this.bottom = this.top + Math.abs( d.y );
-    }
-    else {
-      this.right = 0;
-      this.bottom = 0;
-    }
-  }
+    constructor( topLeft = { x: 0, y: 0 }, size = { x: 0, y: 0 } ) {
+      this.left = topLeft.x;
+      this.top = topLeft.y; 
+      this.right = this.left + Math.abs( size.x );
+      this.bottom = this.top + Math.abs( size.y );
+    };
 
-  Rect.prototype = {
-
-    width: function() {
+    width() {
       return Math.abs( this.right - this.left );
-    },
-    height: function() {
+    }
+
+    height() {
       return Math.abs( this.bottom - this.top );
-    },
-    isIntersecting: function( vec ) {
+    }
+
+    isIntersecting( vec ) {
       return vec.x >= this.left 
           && vec.x <= this.right 
           && vec.y >= this.top
           && vec.y <= this.bottom;
-    },
-    clone: function() {
-      var p = new Vec( this.left, this.top )
-        , d = new Vec( this.width(), this.height() );
+    }
 
-      return new Rect( p, d );
+    clone() {
+      const topLeft = new Vec( this.left, this.top )
+        , size = new Vec( this.width(), this.height() );
+      return new Rect( topLeft, size );
     }
   };
 
   exports.Rect = Rect;
 
-} )();
+})(exports);