Merge pull request #41 from phanecak-maptiler/missing_gulfs

Missing gulfs

README.md

@@ -30,7 +30,8 @@ available options.
   lines, to revert this behavior set `--transportation-name-brunnel=true`
 - `rank` field on `mountain_peak` linestrings only has 3 levels (1: has wikipedia page and name, 2: has name, 3: no name
   or wikipedia page or name)
-- some line and polygon tolerances are different, can be tweaked with `--simplify-tolerance` parameter
+- Some line and polygon tolerances are different, can be tweaked with `--simplify-tolerance` parameter
+- For bigger bays whose label points show above Z9, centerline is used for Z9+
 
 ## Customizing
 

pom.xml

@@ -229,7 +229,7 @@
       <plugin>
         <groupId>com.google.cloud.tools</groupId>
         <artifactId>jib-maven-plugin</artifactId>
-        <version>3.4.0</version>
+        <version>3.4.1</version>
         <configuration>
           <from>
             <image>

src/main/java/org/openmaptiles/layers/WaterName.java

@@ -82,9 +82,13 @@ public class WaterName implements
    */
 
   private static final Logger LOGGER = LoggerFactory.getLogger(WaterName.class);
+  private static final double LOG2 = Math.log(2);
   private static final Set<String> SEA_OR_OCEAN_PLACE = Set.of("sea", "ocean");
   private static final double IMPORTANT_MARINE_REGIONS_JOIN_DISTANCE =
     GeoUtils.metersToPixelAtEquator(0, 50_000) / 256d;
+  private static final int MINZOOM_BAY = 9;
+  private static final int MINZOOM_LAKE = 3;
+  private static final int MINZOOM_SEA_AND_OCEAN = 0;
   private final Translations translations;
   // need to synchronize updates from multiple threads
   private final LongObjectMap<Geometry> lakeCenterlines = Hppc.newLongObjectHashMap();
@@ -214,38 +218,63 @@ public void process(Tables.OsmMarinePoint element, FeatureCollector features) {
   @Override
   public void process(Tables.OsmWaterPolygon element, FeatureCollector features) {
     if (nullIfEmpty(element.name()) != null) {
-      Geometry centerlineGeometry = lakeCenterlines.get(element.source().id());
-      FeatureCollector.Feature feature;
-      int minzoom = 9;
-      String place = element.place();
-      String clazz;
-      if ("bay".equals(element.natural())) {
-        clazz = FieldValues.CLASS_BAY;
-      } else if ("sea".equals(place)) {
-        clazz = FieldValues.CLASS_SEA;
-      } else {
-        clazz = FieldValues.CLASS_LAKE;
-        minzoom = 3;
-      }
-      if (centerlineGeometry != null) {
-        // prefer lake centerline if it exists
-        feature = features.geometry(LAYER_NAME, centerlineGeometry)
-          .setMinPixelSizeBelowZoom(13, 6d * element.name().length());
-      } else {
-        // otherwise just use a label point inside the lake
-        feature = features.pointOnSurface(LAYER_NAME)
-          .setMinZoom(place != null && SEA_OR_OCEAN_PLACE.contains(place) ? 0 : 3)
-          .setMinPixelSize(128); // tiles are 256x256, so 128x128 is 1/4 of a tile
+      try {
+        Geometry centerlineGeometry = lakeCenterlines.get(element.source().id());
+        int minzoom = MINZOOM_BAY;
+        String place = element.place();
+        String clazz;
+        if ("bay".equals(element.natural())) {
+          clazz = FieldValues.CLASS_BAY;
+        } else if ("sea".equals(place)) {
+          clazz = FieldValues.CLASS_SEA;
+        } else {
+          clazz = FieldValues.CLASS_LAKE;
+          minzoom = MINZOOM_LAKE;
+        }
+        if (centerlineGeometry != null) {
+          // prefer lake centerline if it exists, but point will be also used if minzoom bellow 9 is calculated from area
+          // note: Here we're diverging from OpenMapTiles: For bays with minzoom (based on area) point is used between
+          // minzoom and Z8 and for Z9+ centerline is used, while OpenMaptiles sticks with points.
+          setupOsmWaterPolygonFeature(
+            element, features.geometry(LAYER_NAME, centerlineGeometry), clazz, Math.min(minzoom, MINZOOM_BAY))
+              .setMinPixelSizeBelowZoom(13, 6d * element.name().length());
+        }
+
+        // Show a label if a water feature covers at least 1/4 of a tile or z14+
+        Geometry geometry = element.source().worldGeometry();
+        double area = geometry.getArea();
+        minzoom = (int) Math.floor(-1d - Math.log(Math.sqrt(area)) / LOG2);
+        if (place != null && SEA_OR_OCEAN_PLACE.contains(place)) {
+          minzoom = Math.clamp(minzoom, MINZOOM_SEA_AND_OCEAN, 14);
+        } else {
+          minzoom = Math.clamp(minzoom, MINZOOM_LAKE, 14);
+        }
+
+        if (centerlineGeometry == null || minzoom < MINZOOM_BAY) {
+          // otherwise just use a label point inside the lake
+          var feature = setupOsmWaterPolygonFeature(element, features.pointOnSurface(LAYER_NAME), clazz, minzoom);
+          if (centerlineGeometry != null) {
+            // centerline already created, so make sure we're not having both at same zoom level
+            feature.setMaxZoom(MINZOOM_BAY - 1);
+          }
+        }
+      } catch (GeometryException e) {
+        e.log(stats, "omt_water_polygon", "Unable to get geometry for water polygon " + element.source().id());
       }
-      feature
-        .setAttr(Fields.CLASS, clazz)
-        .setBufferPixels(BUFFER_SIZE)
-        .putAttrs(OmtLanguageUtils.getNames(element.source().tags(), translations))
-        .setAttr(Fields.INTERMITTENT, element.isIntermittent() ? 1 : 0)
-        .setMinZoom(minzoom);
     }
   }
 
+  private FeatureCollector.Feature setupOsmWaterPolygonFeature(Tables.OsmWaterPolygon element,
+    FeatureCollector.Feature output, String clazz, int minzoom) {
+    output
+      .setAttr(Fields.CLASS, clazz)
+      .setBufferPixels(BUFFER_SIZE)
+      .putAttrs(OmtLanguageUtils.getNames(element.source().tags(), translations))
+      .setAttr(Fields.INTERMITTENT, element.isIntermittent() ? 1 : 0)
+      .setMinZoom(minzoom);
+    return output;
+  }
+
   private record NaturalEarthRegion(
     Geometry geometry,
     int scalerank