Add NHL arenas layer

layers/nhl-arenas/layer.js

@@ -0,0 +1,30 @@
+import VectorLayer from 'ol/layer/Vector';
+import {Vector as VectorSource} from 'ol/source.js';
+import GeoJSON from 'ol/format/GeoJSON.js';
+
+import {Style, Stroke, Circle, Fill} from 'ol/style.js';
+
+import arenaURL from '/data/nhl-arenas-data.geojson?url'; // TODO: remove `?url`?
+
+import visitedArenas from './visited.js'
+
+const vectorLayer = new VectorLayer({
+    source: new VectorSource({
+        url: arenaURL,
+        format: new GeoJSON,
+    }),
+    // TODO: use '✓' and '✗' (or maybe '✔' and '✘') (from https://en.wikipedia.org/wiki/List_of_Unicode_characters#Dingbats)
+    // TODO: popups with Arena information (name, photo, date visited, score from that day)
+    style: function(feature, resolution) {
+        const base_color = visitedArenas.some(a => a.name == feature.get('name')) ? '#008800' : '#FF0000';
+        return new Style({
+            image: new Circle({
+                radius: 50/Math.pow(resolution, 1/4),
+                fill: new Fill({color: base_color + '33'}),
+                stroke: new Stroke({color: base_color, width: 1}),
+            }),
+        });
+    }
+});
+
+export default vectorLayer;