WIP add google map tiles layer

Author: paul121

src/instance/methods/layer.js

@@ -1,6 +1,7 @@
 // Import source types, layer types, and formats.
 import VectorSource from 'ol/source/Vector';
 import Cluster from 'ol/source/Cluster';
+import Google from 'ol/source/Google';
 import TileArcGISRest from 'ol/source/TileArcGISRest';
 import TileWMS from 'ol/source/TileWMS';
 import XYZ from 'ol/source/XYZ';
@@ -103,6 +104,28 @@ function addGeoJSONLayer({
   return layer;
 }
 
+// Add a Google Map Tiles layer to the map.
+function addGoogleMapTilesLayer({
+  title = 'google-map-tiles', key, mapType = 'satellite', language = 'en-US', region = 'US', apiOptions = null, visible = true, base = false,
+}) {
+  const source = new Google({
+    key,
+    mapType,
+    language,
+    region,
+    apiOptions,
+    scale: 'scaleFactor2x',
+    highDpi: true,
+  });
+  const layer = new TileLayer({
+    title,
+    source,
+    visible,
+    type: base ? 'base' : 'normal',
+  });
+  return layer;
+}
+
 // Add a Tile ArcGIS MapServer layer to the map.
 function addTileArcGISMapServerLayer({
   title = 'arcgis-tile', url, params, visible = true, base = false, attribution = '', crossOrigin = null,
@@ -226,6 +249,12 @@ export default function addLayer(type, opts = {}) {
     }
     layer = addGeoJSONLayer(opts);
   }
+  if (type.toLowerCase() === 'google') {
+    if (!opts.key) {
+      throw new Error('Missing a Google Map Tiles API key.');
+    }
+    layer = addGoogleMapTilesLayer(opts);
+  }
   if (type.toLowerCase() === 'arcgis-tile') {
     if (!opts.url) {
       throw new Error('Missing a ArcGIS MapServer url.');