Create camera, layers and projection if not specified

skeleton.html

@@ -7,23 +7,14 @@
                 <script src="http://localhost:9810/compile?id=ol&mode=RAW" type="text/javascript"></script>
 		<script>
 
-			var projection = ol.Projection.createFromCode('EPSG:3857');
+			var target = document.getElementById('map');
+			var map = new ol.Map(target);
 
 			var layer = ol.TileLayer.createOpenStreetMap({
 				'opacity': 0.5,
 				'visible': true
 			});
-
+			map.getLayers().push(layer);
-			var layers = new ol.Array([layer]);
-
-			var camera = new ol.Camera();
-
-			var target = document.getElementById('map');
-			var map = new ol.Map(target, {
-				'camera': camera,
-				'layers': layers,
-				'projection': projection
-			});
 
 		</script>
 	</body>

src/ol/map.js

@@ -1,5 +1,6 @@
 goog.provide('ol.Map');
 
+goog.require('goog.object');
 goog.require('ol.Array');
 goog.require('ol.Camera');
 goog.require('ol.DOMMapRenderer');
@@ -68,9 +69,19 @@ ol.Map = function(target, opt_values) {
 
   goog.asserts.assert(!goog.isNull(this.mapRenderer_));
 
-  if (goog.isDef(opt_values)) {
+  var values = goog.isDef(opt_values) ? goog.object.clone(opt_values) : {};
-    this.setValues(opt_values);
+
+  if (!(ol.MapProperty.CAMERA in values)) {
+    values[ol.MapProperty.CAMERA] = new ol.Camera();
   }
+  if (!(ol.MapProperty.LAYERS in values)) {
+    values[ol.MapProperty.LAYERS] = new ol.Array();
+  }
+  if (!(ol.MapProperty.PROJECTION in values)) {
+    values[ol.MapProperty.PROJECTION] = ol.Projection.createFromCode('EPSG:3857');
+  }
+
+  this.setValues(values);
 
 };
 goog.inherits(ol.Map, ol.Object);