Geomap: Route/path visualization (#43554)

Co-authored-by: Ryan McKinley <ryantxu@gmail.com>

public/app/features/geo/utils/frameVectorSource.ts

@@ -1,8 +1,8 @@
 import { Feature } from 'ol';
-import { Geometry } from 'ol/geom';
+import { Geometry, LineString, Point } from 'ol/geom';
 import VectorSource from 'ol/source/Vector';
 
-import { DataFrame } from '@grafana/data';
+import { DataFrame, Field } from '@grafana/data';
 
 import { getGeometryField, LocationFieldMatchers } from './location';
 
@@ -34,4 +34,26 @@ export class FrameVectorSource<T extends Geometry = Geometry> extends VectorSour
     // only call this at the end
     this.changed();
   }
+
+  updateLineString(frame: DataFrame) {
+    this.clear(true);
+    const info = getGeometryField(frame, this.location);
+    if (!info.field) {
+      this.changed();
+      return;
+    }
+
+    const field = info.field as Field<Point>;
+    const geometry = new LineString(field.values.toArray().map((p) => p.getCoordinates())) as Geometry;
+    this.addFeatureInternal(
+      new Feature({
+        frame,
+        rowIndex: 0,
+        geometry: geometry as T,
+      })
+    );
+
+    // only call this at the end
+    this.changed();
+  }
 }