Encode a constant layer ID as part of feature IDs

tiles/src/main/java/com/protomaps/basemap/feature/FeatureId.java

@@ -8,7 +8,15 @@ public class FeatureId {
 
   private FeatureId() {}
 
-  public static long create(SourceFeature sf) {
+  // uses 44 bits for the Feature ID,
+  // 2 bits for class (OSM node/way/relation or Not OSM)
+  // 6 bits for the layer id
+
+  public static long encode(int layerId) {
+    return (layerId << 46);
+  }
+
+  public static long encode(int layerId, SourceFeature sf) {
     if (sf instanceof OsmSourceFeature osmFeature) {
       long elemType;
       var element = osmFeature.originalElement();
@@ -19,8 +27,8 @@ public static long create(SourceFeature sf) {
       } else {
         elemType = 0x1;
       }
-      return (elemType << 44) | element.id();
+      return (layerId << 46) | (elemType << 44) | element.id();
     }
-    return sf.id();
+    return (layerId << 46) | sf.id();
   }
 }

tiles/src/main/java/com/protomaps/basemap/layers/Boundaries.java

@@ -16,6 +16,8 @@
 public class Boundaries implements ForwardingProfile.OsmRelationPreprocessor,
   ForwardingProfile.LayerPostProcesser {
 
+  final int LAYER_ID = 0;
+
   @Override
   public String name() {
     return "boundaries";
@@ -214,7 +216,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
 
         if (!kind.isEmpty()) {
           var line = features.line(this.name())
-            .setId(FeatureId.create(sf))
+            .setId(FeatureId.encode(LAYER_ID, sf))
             // Core Tilezen schema properties
             .setAttr("kind", kind)
             .setAttr("kind_detail", minAdminLevel.getAsInt())

tiles/src/main/java/com/protomaps/basemap/layers/Buildings.java

@@ -23,6 +23,8 @@ public class Buildings implements ForwardingProfile.LayerPostProcesser {
   static final String HEIGHT_KEY = "height";
   static final String MIN_HEIGHT_KEY = "min_height";
 
+  final int LAYER_ID = 1;
+
   @Override
   public String name() {
     return "buildings";
@@ -78,7 +80,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feature = features.polygon(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         // Core Tilezen schema properties
         .setAttr("kind", kind)
         // Core OSM tags for different kinds of places
@@ -108,7 +110,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
       if (housenumberFeature != null) {
         housenumberFeature
-          .setId(FeatureId.create(sf))
+          .setId(FeatureId.encode(LAYER_ID, sf))
           .setAttr("addr_housenumber", sf.getString("addr:housenumber"))
           .setAttr("addr_street", sf.getString("addr:street"))
           .setAttr("kind", "address")

tiles/src/main/java/com/protomaps/basemap/layers/Earth.java

@@ -12,6 +12,8 @@
 import org.locationtech.jts.geom.Point;
 
 public class Earth implements ForwardingProfile.LayerPostProcesser {
+
+  final int LAYER_ID = 2;
   @Override
   public String name() {
     return "earth";
@@ -20,7 +22,7 @@ public String name() {
   public void processPreparedOsm(SourceFeature ignoredSf, FeatureCollector features) {
     features.polygon(this.name())
       .setAttr("kind", "earth")
-      .setId(0)
+      .setId(FeatureId.encode(LAYER_ID))
       .setZoomRange(6, 15).setBufferPixels(8);
   }
 
@@ -54,7 +56,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
     if (sf.canBeLine() && !sf.canBePolygon() && sf.hasTag("natural", "cliff")) {
       int minZoom = 12;
       var feat = features.line(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         .setAttr("min_zoom", minZoom + 1)
         .setAttr("kind", "cliff")
         .setZoomRange(minZoom, 15);

tiles/src/main/java/com/protomaps/basemap/layers/Landcover.java

@@ -10,6 +10,7 @@
 import java.util.Map;
 
 public class Landcover implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 3;
 
   static final Map<String, String> kindMapping = Map.of("urban", "urban_area", "crop", "farmland", "grass", "grassland",
     "trees", "forest", "snow", "glacier", "shrub", "scrub");
@@ -25,7 +26,7 @@ public void processLandcover(SourceFeature sf, FeatureCollector features) {
     Integer sortKey = sortKeyMapping.getOrDefault(daylightClass, 6);
 
     features.polygon(this.name())
-      .setId(FeatureId.create(sf))
+      .setId(FeatureId.encode(LAYER_ID, sf))
       .setAttr("kind", kind)
       .setZoomRange(0, 7)
       .setSortKey(sortKey)

tiles/src/main/java/com/protomaps/basemap/layers/Landuse.java

@@ -11,6 +11,7 @@
 import java.util.List;
 
 public class Landuse implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 4;
 
   public void processOsm(SourceFeature sf, FeatureCollector features) {
     if (sf.canBePolygon() && (sf.hasTag("aeroway", "aerodrome", "runway") ||
@@ -151,7 +152,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       features.polygon(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         // Core Tilezen schema properties
         .setAttr("kind", kind)
         .setAttr("sort_rank", 189)

tiles/src/main/java/com/protomaps/basemap/layers/Places.java

@@ -16,6 +16,7 @@
 import java.util.concurrent.atomic.AtomicInteger;
 
 public class Places implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 5;
 
   private NaturalEarthDb naturalEarthDb;
 
@@ -266,7 +267,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feat = features.point(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         // Core Tilezen schema properties
         .setAttr("kind", kind)
         .setAttr("kind_detail", place)

tiles/src/main/java/com/protomaps/basemap/layers/Pois.java

@@ -15,6 +15,7 @@
 import java.util.List;
 
 public class Pois implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 6;
 
   private QrankDb qrankDb;
 
@@ -443,7 +444,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
         var polyLabelPosition = features.pointOnSurface(this.name())
           // all POIs should receive their IDs at all zooms
           // (there is no merging of POIs like with lines and polygons in other layers)
-          .setId(FeatureId.create(sf))
+          .setId(FeatureId.encode(LAYER_ID, sf))
           // Core Tilezen schema properties
           .setAttr("kind", kind)
           // While other layers don't need min_zoom, POIs do for more predictable client-side label collisions
@@ -485,7 +486,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
         var pointFeature = features.point(this.name())
           // all POIs should receive their IDs at all zooms
           // (there is no merging of POIs like with lines and polygons in other layers)
-          .setId(FeatureId.create(sf))
+          .setId(FeatureId.encode(LAYER_ID, sf))
           // Core Tilezen schema properties
           .setAttr("kind", kind)
           // While other layers don't need min_zoom, POIs do for more predictable client-side label collisions

tiles/src/main/java/com/protomaps/basemap/layers/Roads.java

@@ -18,6 +18,7 @@
 import java.util.*;
 
 public class Roads implements ForwardingProfile.LayerPostProcessor, ForwardingProfile.OsmRelationPreprocessor {
+  final int LAYER_ID = 7;
 
   private CountryCoder countryCoder;
 
@@ -190,7 +191,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feat = features.line("roads")
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         .setAttr("kind", kind)
         // To power better client label collisions
         .setAttr("min_zoom", minZoom + 1)
@@ -294,7 +295,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feature = features.line(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         .setAttr("kind", kind)
         // Used for client-side label collisions
         .setAttr("min_zoom", minZoom + 1)

tiles/src/main/java/com/protomaps/basemap/layers/Transit.java

@@ -7,6 +7,7 @@
 import java.util.List;
 
 public class Transit implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 8;
 
   @Override
   public String name() {

tiles/src/main/java/com/protomaps/basemap/layers/Water.java

@@ -14,6 +14,7 @@
 import java.util.List;
 
 public class Water implements ForwardingProfile.LayerPostProcesser {
+  final int LAYER_ID = 9;
 
   private static final double WORLD_AREA_FOR_70K_SQUARE_METERS =
     Math.pow(GeoUtils.metersToPixelAtEquator(0, Math.sqrt(70_000)) / 256d, 2);
@@ -25,7 +26,7 @@ public String name() {
 
   public void processPreparedOsm(SourceFeature ignoredSf, FeatureCollector features) {
     features.polygon(this.name())
-      .setId(0)
+      .setId(FeatureId.encode(LAYER_ID))
       .setAttr("kind", "ocean")
       .setAttr("sort_rank", 200)
       .setZoomRange(6, 15).setBufferPixels(8);
@@ -200,7 +201,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feat = features.line(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         .setAttr("kind", kind)
         // Used for client-side label collisions
         .setAttr("min_zoom", minZoom + 1)
@@ -249,7 +250,7 @@ public void processOsm(SourceFeature sf, FeatureCollector features) {
       }
 
       var feat = features.point(this.name())
-        .setId(FeatureId.create(sf))
+        .setId(FeatureId.encode(LAYER_ID, sf))
         .setAttr("kind", kind)
         // Used for client-side label collisions
         .setAttr("min_zoom", minZoom + 1)