Merge branch '396-resolution-of-exported-png' into 'master'

Resolve "Resolution of exported .png"

Closes #396

See merge request piotr.gawron/minerva!305

frontend-js/src/main/js/gui/AbstractGuiElement.js

@@ -31,6 +31,10 @@ AbstractGuiElement.prototype.setMap = function (map) {
   this._map = map;
 };
 
+/**
+ *
+ * @returns {CustomMap}
+ */
 AbstractGuiElement.prototype.getMap = function () {
   return this._map;
 };

frontend-js/src/main/js/gui/ContextMenu.js

@@ -122,13 +122,14 @@ ContextMenu.prototype.createExportAsImageSubmenu = function () {
     converters.forEach(function (converter) {
       submenu.addOption(converter.name, function () {
         return map.getVisibleDataOverlays().then(function (visibleDataOverlays) {
+          var submapId = map.getActiveSubmapId();
 
           return ServerConnector.getImageDownloadUrl({
             polygonString: map.getSelectedPolygon(),
-            modelId: map.getActiveSubmapId(),
+            modelId: submapId,
             handlerClass: converter.handler,
             backgroundOverlayId: map.getGoogleMap().getMapTypeId(),
-            zoomLevel: map.getGoogleMap().getZoom(),
+            zoomLevel: map.getSubmapById(submapId).getGoogleMap().getZoom(),
             overlayIds: extractDataOverlayIds(visibleDataOverlays)
           });
         }).then(function (url) {