Create a layer with trams. acteng/atip#463

README.md

@@ -83,6 +83,7 @@ ATIP can display extra contextual layers:
   - Cycle parking
   - Existing cycle paths
   - Crossings
+  - Tram lines
 - the [Major Road Network](https://www.data.gov.uk/dataset/95f58bfa-13d6-4657-9d6f-020589498cfd/major-road-network)
 - Boundaries
   - Parliament constituency boundaries, from [OS Boundary-Line](https://www.ordnancesurvey.co.uk/products/boundary-line)
@@ -107,7 +108,7 @@ is a single GeoJSON file if it's small enough, or
 To run this:
 
 1.  Get `england-latest.osm.pbf` from Geofabrik. The `split_uk_osm.sh` script above does this.
-2.  Run `cd layers; ./generate_layers.py --osm_input=../england-latest.osm.pbf --schools --hospitals --mrn --parliamentary_constituencies --combined_authorities --local_authority_districts --local_planning_authorities --sports_spaces --railway_stations --bus_routes --crossings --cycle_parking --cycle_paths --ncn --wards --vehicle_counts --pct --local_authorities_for_sketcher --transport_authorities_for_sketcher`
+2.  Run `cd layers; ./generate_layers.py --osm_input=../england-latest.osm.pbf --schools --hospitals --mrn --parliamentary_constituencies --combined_authorities --local_authority_districts --local_planning_authorities --sports_spaces --railway_stations --bus_routes --crossings --cycle_parking --cycle_paths --ncn --wards --vehicle_counts --pct --local_authorities_for_sketcher --transport_authorities_for_sketcher --trams`
 3.  Pick an arbitrary version number, and upload the files: `for x in output/*; do aws s3 cp --dry $x s3://atip.uk/layers/v1/; done`
 
 If you're rerunning the script for the same output, you may need to manually delete the output files from the previous run.

layers/generate_layers.py

@@ -20,6 +20,7 @@ def main():
     parser.add_argument("--parliamentary_constituencies", action="store_true")
     parser.add_argument("--railway_stations", action="store_true")
     parser.add_argument("--crossings", action="store_true")
+    parser.add_argument("--trams", action="store_true")
     parser.add_argument("--sports_spaces", action="store_true")
     parser.add_argument("--wards", action="store_true")
     parser.add_argument("--combined_authorities", action="store_true")
@@ -122,6 +123,10 @@ def main():
         made_any = True
         osm.makeCrossings(args.osm_input)
 
+    if args.trams:
+        made_any = True
+        osm.makeTrams(args.osm_input)
+
     if args.imd:
         made_any = True
         census.makeIMD(args.imd)

layers/osm.py

@@ -217,7 +217,40 @@ def fixProps(inputProps):
         return outputProps
 
     cleanUpGeojson(tmpGeojsonFilepath, fixProps)
-    convertGeoJsonToPmtiles(
-        tmpGeojsonFilepath, outputFilepath, autoZoom=True
+    convertGeoJsonToPmtiles(tmpGeojsonFilepath, outputFilepath, autoZoom=True)
+
+
+def makeTrams(osm_input):
+    if not osm_input:
+        raise Exception("You must specify --osm_input")
+
+    filename = "trams"
+    tmp = f"tmp_{filename}"
+    ensureEmptyTempDirectoryExists(tmp)
+
+    run(
+        [
+            "osmium",
+            "tags-filter",
+            osm_input,
+            # Manchester's trams are tagged as light_rail
+            "nwr/railway=tram,light_rail",
+            "-o",
+            f"{tmp}/extract.osm.pbf",
+        ]
+    )
+    convertPbfToGeoJson(
+        f"{tmp}/extract.osm.pbf",
+        f"{tmp}/{filename}.geojson",
+        "linestring",
+        includeOsmID=True,
     )
 
+    def fixProps(inputProps):
+        return {
+            "osm_id": inputProps["@id"],
+        }
+
+    cleanUpGeojson(f"{tmp}/{filename}.geojson", fixProps)
+
+    convertGeoJsonToPmtiles(f"{tmp}/{filename}.geojson", f"output/{filename}.pmtiles")