Refactor water area MSS

water.mss

@@ -17,48 +17,31 @@
       }
     }
   }
+}
 
-  [waterway = 'dock'],
-  [waterway = 'canal'] {
-    [zoom >= 9]::waterway {
-      polygon-fill: @water-color;
-      [way_pixels >= 4] {
-        polygon-gamma: 0.75;
-      }
-      [way_pixels >= 64] {
-        polygon-gamma: 0.6;
-      }
-    }
-  }
+/*
+ * Water areas, of all types. Because they are rendered all the same,
+ * attachments can be used to reduce combinational rules
+ */
 
-  [landuse = 'basin'][zoom >= 7]::landuse {
-    polygon-fill: @water-color;
-    [way_pixels >= 4] {
-      polygon-gamma: 0.75;
-    }
-    [way_pixels >= 64] {
-      polygon-gamma: 0.6;
-    }
-  }
+#water-areas[waterway = 'dock'][zoom >= 9]::waterway,
+#water-areas[waterway = 'canal'][zoom >= 9]::waterway,
+#water-areas[landuse = 'basin'][zoom >= 7]::landuse,
+#water-areas[natural = 'water'][zoom >= 6]::natural,
+#water-areas[landuse = 'reservoir'][zoom >= 6]::landuse,
+#water-areas[waterway = 'riverbank'][zoom >= 6]::waterway,
+.ocean {
+  polygon-fill: @water-color;
 
-  [natural = 'water']::natural,
-  [landuse = 'reservoir']::landuse,
-  [waterway = 'riverbank']::waterway {
-    [zoom >= 6] {
-      polygon-fill: @water-color;
-      [way_pixels >= 4] {
-        polygon-gamma: 0.75;
-      }
-      [way_pixels >= 64] {
-        polygon-gamma: 0.6;
-      }
-    }
+  // Only the SQL layers have way_pixels
+  #water-areas[way_pixels >= 4] {
+    polygon-gamma: 0.75;
+  }
+  #water-areas[way_pixels >= 64] {
+    polygon-gamma: 0.6;
   }
 }
 
-.ocean {
-  polygon-fill: @water-color;
-}
 #water-lines-casing {
   [waterway = 'stream'],
   [waterway = 'ditch'],