@Override
  public boolean isOverlay() {
    return true; // when true sets type=overlay, otherwise type=baselayer
  }
Builds a map of bike routes from ways contained in OpenStreetMap relations tagged with
<a href="https://wiki.openstreetmap.org/wiki/Tag:route=bicycle">route=bicycle</a>.
<p>
To run this example:
<ol>
<li>Download a .osm.pbf extract (see <a href="https://download.geofabrik.de/">Geofabrik download site</a>)</li>
<li>then build the examples: {@code mvn clean package}</li>
<li>then run this example:
{@code java -cp target/*-with-deps.jar com.onthegomap.planetiler.examples.BikeRouteOverlay osm_path="path/to/data.osm.pbf" mbtiles="data/output.mbtiles"}</li>
<li>then run the demo tileserver: {@code tileserver-gl-light data/bikeroutes.mbtiles}</li>
<li>and view the output at <a href="http://localhost:8080">localhost:8080</a></li>
</ol>
planetiler-examples/src/main/java/com/onthegomap/planetiler/examples/BikeRouteOverlay.java