Reverted performance related improvement to clusters-dbscan that broke builds

packages/turf-clusters-dbscan/index.ts

@@ -1,8 +1,8 @@
 import { GeoJsonProperties, FeatureCollection, Point } from "geojson";
 import { clone } from "@turf/clone";
-import { Units } from "@turf/helpers";
-import KDBush from "kdbush";
-import * as geokdbush from "geokdbush";
+import { distance } from "@turf/distance";
+import { degreesToRadians, lengthToDegrees, Units } from "@turf/helpers";
+import RBush from "rbush";
 
 /**
  * Point classification within the cluster.
@@ -80,13 +80,11 @@ function clustersDbscan(
   // Defaults
   const minPoints = options.minPoints || 3;
 
+  // Calculate the distance in degrees for region queries
+  const latDistanceInDegrees = lengthToDegrees(maxDistance, options.units);
+
   // Create a spatial index
-  const kdIndex = new KDBush(points.features.length);
-  // Index each point for spatial queries
-  for (const point of points.features) {
-    kdIndex.add(point.geometry.coordinates[0], point.geometry.coordinates[1]);
-  }
-  kdIndex.finish();
+  var tree = new RBush(points.features.length);
 
   // Keeps track of whether a point has been visited or not.
   var visited = points.features.map((_) => false);
@@ -100,22 +98,54 @@ function clustersDbscan(
   // Keeps track of the clusterId for each point
   var clusterIds: number[] = points.features.map((_) => -1);
 
+  // Index each point for spatial queries
+  tree.load(
+    points.features.map((point, index) => {
+      var [x, y] = point.geometry.coordinates;
+      return {
+        minX: x,
+        minY: y,
+        maxX: x,
+        maxY: y,
+        index: index,
+      } as IndexedPoint;
+    })
+  );
+
   // Function to find neighbors of a point within a given distance
   const regionQuery = (index: number): IndexedPoint[] => {
     const point = points.features[index];
     const [x, y] = point.geometry.coordinates;
 
-    return (
-      geokdbush
-        // @ts-expect-error 2345 until https://github.com/mourner/geokdbush/issues/20 is resolved
-        .around<number>(kdIndex, x, y, undefined, maxDistance)
-        .map((id) => ({
-          minX: points.features[id].geometry.coordinates[0],
-          minY: points.features[id].geometry.coordinates[1],
-          maxX: points.features[id].geometry.coordinates[0],
-          maxY: points.features[id].geometry.coordinates[1],
-          index: id,
-        }))
+    const minY = Math.max(y - latDistanceInDegrees, -90.0);
+    const maxY = Math.min(y + latDistanceInDegrees, 90.0);
+
+    const lonDistanceInDegrees = (function () {
+      // Handle the case where the bounding box crosses the poles
+      if (minY < 0 && maxY > 0) {
+        return latDistanceInDegrees;
+      }
+      if (Math.abs(minY) < Math.abs(maxY)) {
+        return latDistanceInDegrees / Math.cos(degreesToRadians(maxY));
+      } else {
+        return latDistanceInDegrees / Math.cos(degreesToRadians(minY));
+      }
+    })();
+
+    const minX = Math.max(x - lonDistanceInDegrees, -360.0);
+    const maxX = Math.min(x + lonDistanceInDegrees, 360.0);
+
+    // Calculate the bounding box for the region query
+    const bbox = { minX, minY, maxX, maxY };
+    return (tree.search(bbox) as ReadonlyArray<IndexedPoint>).filter(
+      (neighbor) => {
+        const neighborIndex = neighbor.index;
+        const neighborPoint = points.features[neighborIndex];
+        const distanceInKm = distance(point, neighborPoint, {
+          units: "kilometers",
+        });
+        return distanceInKm <= maxDistance;
+      }
     );
   };
 

packages/turf-clusters-dbscan/package.json

@@ -62,6 +62,7 @@
     "@turf/centroid": "workspace:*",
     "@turf/clusters": "workspace:*",
     "@types/benchmark": "^2.1.5",
+    "@types/rbush": "^3.0.4",
     "@types/tape": "^5.8.1",
     "benchmark": "^2.1.4",
     "chromatism": "^3.0.0",
@@ -75,12 +76,11 @@
   },
   "dependencies": {
     "@turf/clone": "workspace:*",
+    "@turf/distance": "workspace:*",
     "@turf/helpers": "workspace:*",
     "@turf/meta": "workspace:*",
     "@types/geojson": "^7946.0.10",
-    "@types/geokdbush": "^1.1.5",
-    "geokdbush": "^2.0.1",
-    "kdbush": "^4.0.2",
+    "rbush": "^3.0.1",
     "tslib": "^2.8.1"
   }
 }