Merge pull request #505 from Harry-R/empty-basemap

Add "Empty" base map layer

ember/app/components/base-map.js

@@ -66,6 +66,7 @@ export default Ember.Component.extend({
     this.addMWPLayers();
     this.addBingLayers();
     this.addMapboxLayer();
+    this.addEmptyLayer();
 
     let query = parseQueryString(window.location.search);
     this.set('baseLayer', query.baselayer);
@@ -265,4 +266,18 @@ export default Ember.Component.extend({
     map.addLayer(road);
     map.addLayer(hybrid);
   },
+
+  addEmptyLayer() {
+    let empty_layer = new ol.layer.Tile({
+    });
+    empty_layer.setProperties({
+      'name': 'Empty',
+      'id': 'Empty',
+      'base_layer': true,
+      'display_in_layer_switcher': true,
+    });
+
+    this.get('map').addLayer(empty_layer);
+  },
+
 });

ember/app/styles/_map.scss

@@ -1,3 +1,7 @@
+.ol-viewport {
+  background-color: white
+}
+
 .ol-viewport .plane_marker {
   position: absolute;
   min-height: 1em;