Added rendering for ref on public_transport=stop_positions

project.mml

@@ -2240,6 +2240,22 @@ Layer:
         ) AS protected_areas_text
     properties:
       minzoom: 13
+  - id: train-stop-positions
+    geometry: point
+    <<: *extents
+    Datasource:
+      <<: *osm2pgsql
+      table: |-
+        (SELECT
+          way,
+          ref
+        FROM planet_osm_point
+        WHERE tags @> 'public_transport=>stop_position'
+          AND tags @> 'train=>yes'
+          AND ref IS NOT NULL
+        ) AS stop_positions
+    properties:
+      minzoom: 18
   - id: amenity-low-priority
     geometry: point
     <<: *extents

style/stations.mss

@@ -120,3 +120,22 @@
     }
   }
 }
+
+#train-stop-positions {
+  [zoom >= 18] {
+    text-name: [ref];
+    text-face-name: @bold-fonts;
+    text-fill: @transportation-icon;
+    text-halo-radius: @standard-halo-radius * 1.5;
+    text-halo-fill: @standard-halo-fill;
+    text-wrap-width: 0;
+    text-size: 11;
+    [zoom >= 19] {
+      text-size: 13;
+      text-halo-radius: @standard-halo-radius * 2.0;
+    }
+    [zoom >= 20] {
+      text-size: 15;
+    }
+  }
+}