From 14cdab884570133d2fbdba30ebc689f109419288 Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Thu, 2 Jul 2026 05:49:34 +0100
Subject: [PATCH] Fix getClusters dropping points exactly on the query bbox
 edge

Points are stored as Float32 (fround), but the getClusters range query
was built from full-precision Float64 bounds. fround can round a stored
coordinate slightly outside its exact value, so a point whose lng/lat
equals a bbox edge fell just outside the inclusive range and was
dropped. Project the query bounds through the same fround so the edge
comparison is exact. Fixes #234.
---
 index.js     |  2 +-
 test/test.js | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/index.js b/index.js
index 4dce8d36..0d339b28 100644
--- a/index.js
+++ b/index.js
@@ -102,7 +102,7 @@ export default class Supercluster {
         }
 
         const tree = this.trees[this._limitZoom(zoom)];
-        const ids = tree.range(lngX(minLng), latY(maxLat), lngX(maxLng), latY(minLat));
+        const ids = tree.range(fround(lngX(minLng)), fround(latY(maxLat)), fround(lngX(maxLng)), fround(latY(minLat)));
         const data = tree.data;
         const clusters = [];
         for (const id of ids) {
diff --git a/test/test.js b/test/test.js
index 5fb05107..4f50b204 100644
--- a/test/test.js
+++ b/test/test.js
@@ -179,3 +179,15 @@ test('does not throw on zero items', () => {
         assert.deepEqual(index.getClusters([-180, -85, 180, 85], 0), []);
     });
 });
+
+test('returns points that lie exactly on the query bbox edge', () => {
+    const index = new Supercluster().load([
+        {type: 'Feature', properties: {name: 'a'}, geometry: {type: 'Point', coordinates: [-123.211605, 43.972615]}},
+        {type: 'Feature', properties: {name: 'b'}, geometry: {type: 'Point', coordinates: [-123.245515, 43.9150233333333]}},
+        {type: 'Feature', properties: {name: 'c'}, geometry: {type: 'Point', coordinates: [-123.192528333333, 44.0307166666667]}},
+        {type: 'Feature', properties: {name: 'd'}, geometry: {type: 'Point', coordinates: [-123.194573333333, 44.0107]}}
+    ]);
+    const bbox = [-123.245515, 43.9150233333333, -123.192528333333, 44.0307166666667];
+    const names = index.getClusters(bbox, 16).map(p => p.properties.name).sort();
+    assert.deepEqual(names, ['a', 'b', 'c', 'd']);
+});