From 4715d4999e2d568f9ce645ba6c6446b4c35598b6 Mon Sep 17 00:00:00 2001
From: Ilya Boyandin <ilyabo@gmail.com>
Date: Sun, 24 Mar 2019 21:23:55 +0100
Subject: [PATCH] Adding input location weight property support

---
 demo/worker.js |  1 +
 index.js       | 17 +++++++++++------
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/demo/worker.js b/demo/worker.js
index 091c585..4727158 100644
--- a/demo/worker.js
+++ b/demo/worker.js
@@ -9,6 +9,7 @@ let index;
 getJSON('../test/fixtures/places.json', (geojson) => {
     console.log(`loaded ${  geojson.length  } points JSON in ${  (Date.now() - now) / 1000  }s`);
 
+    geojson.features.forEach((d) => { d.properties.weight = Math.random() * 1000; });
     index = new Supercluster({
         log: true,
         radius: 60,
diff --git a/index.js b/index.js
index 07db99d..4478498 100644
--- a/index.js
+++ b/index.js
@@ -228,9 +228,10 @@ export default class Supercluster {
             const tree = this.trees[zoom + 1];
             const neighborIds = tree.within(p.x, p.y, r);
 
+            let weight = p.weight || 1;
             let numPoints = p.numPoints || 1;
-            let wx = p.x * numPoints;
-            let wy = p.y * numPoints;
+            let wx = p.x * weight;
+            let wy = p.y * weight;
 
             const clusterProperties = reduce ? this._map(p, true) : null;
 
@@ -243,10 +244,12 @@ export default class Supercluster {
                 if (b.zoom <= zoom) continue;
                 b.zoom = zoom; // save the zoom (so it doesn't get processed twice)
 
+                const weight2 = b.weight || 1;
                 const numPoints2 = b.numPoints || 1;
-                wx += b.x * numPoints2; // accumulate coordinates for calculating weighted center
-                wy += b.y * numPoints2;
+                wx += b.x * weight2; // accumulate coordinates for calculating weighted center
+                wy += b.y * weight2;
 
+                weight += weight2;
                 numPoints += numPoints2;
                 b.parentId = id;
 
@@ -259,7 +262,7 @@ export default class Supercluster {
                 clusters.push(p);
             } else {
                 p.parentId = id;
-                clusters.push(createCluster(wx / numPoints, wy / numPoints, id, numPoints, clusterProperties));
+                clusters.push(createCluster(wx / weight, wy / weight, id, numPoints, weight, clusterProperties));
             }
         }
 
@@ -276,7 +279,7 @@ export default class Supercluster {
     }
 }
 
-function createCluster(x, y, id, numPoints, properties) {
+function createCluster(x, y, id, numPoints, weight, properties) {
     return {
         x, // weighted cluster center
         y,
@@ -284,6 +287,7 @@ function createCluster(x, y, id, numPoints, properties) {
         id, // encodes index of the first child of the cluster and its zoom level
         parentId: -1, // parent cluster id
         numPoints,
+        weight,
         properties
     };
 }
@@ -293,6 +297,7 @@ function createPointCluster(p, id) {
     return {
         x: lngX(x), // projected point coordinates
         y: latY(y),
+        weight: p.properties.weight || 1,
         zoom: Infinity, // the last zoom the point was processed at
         index: id, // index of the source feature in the original input array,
         parentId: -1 // parent cluster id