From 1f9ffa3ec3f7ffc25551e43ef5aa7f185bc3fe41 Mon Sep 17 00:00:00 2001
From: fuzhenn <fuzhen@maptalks.org>
Date: Tue, 4 Jul 2017 20:19:47 +0800
Subject: [PATCH] fix possible null clusters

---
 index.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.js b/index.js
index 577809f..ed6b8c9 100644
--- a/index.js
+++ b/index.js
@@ -323,6 +323,9 @@ ClusterLayer.registerRenderer('canvas', class extends maptalks.renderer.VectorLa
     }
 
     _drawClusters(clusters, ratio, matrix) {
+        if (!clusters) {
+            return;
+        }
         matrix = matrix ? matrix['container'] : null;
         this._clusterMaskExtent = this.prepareCanvas();
         const map = this.getMap(),