Document water_name and waterway

layers/waterway/README.md

@@ -0,0 +1,20 @@
+# waterway
+
+Rivers based of OpenStreetMap [waterways](http://wiki.openstreetmap.org/wiki/Waterways) for *z8* to *z14*
+and Natural Earth rivers and lake centerlines from *z3* to *z7*.
+Too short linestrings are filtered out for some zoom levels. Waterways do no not have a `subclass`.
+
+## Fields
+
+- **class**: The original value of the [`waterway`](http://wiki.openstreetmap.org/wiki/Key:waterway) tag.
+Can be one of [`stream`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dstream),
+[`river`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Driver),
+[`canal`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dcanal),
+[`drain`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Ddrain),
+[`ditch`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dditch)`.
+
+## Mapping
+
+![](mapping.png)
+
+

layers/waterway/waterway.yaml

@@ -1,8 +1,18 @@
 layer:
   id: "waterway"
   description: |
-      OpenStreetMap waterways.
+      Rivers based of OpenStreetMap [waterways](http://wiki.openstreetmap.org/wiki/Waterways) for *z8* to *z14*
+      and Natural Earth rivers and lake centerlines from *z3* to *z7*.
+      Too short linestrings are filtered out for some zoom levels. Waterways do no not have a `subclass`.
   buffer_size: 4
+  fields:
+    class: |
+        The original value of the [`waterway`](http://wiki.openstreetmap.org/wiki/Key:waterway) tag.
+        Can be one of [`stream`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dstream),
+        [`river`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Driver),
+        [`canal`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dcanal),
+        [`drain`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Ddrain),
+        [`ditch`](http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dditch)`.
   datasource:
     geometry_field: geometry
     query: (SELECT geometry, class FROM layer_waterway(!bbox!, z(!scale_denominator!))) AS t