From fe2af496370572701c6f41aea9869e29404b8f50 Mon Sep 17 00:00:00 2001
From: Sergey Alexandrov <alexandrov88@gmail.com>
Date: Mon, 26 Mar 2018 15:46:26 +0200
Subject: [PATCH] Warn and skip adding normal cloud if it is empty

---
 .../include/pcl/visualization/impl/pcl_visualizer.hpp      | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/visualization/include/pcl/visualization/impl/pcl_visualizer.hpp b/visualization/include/pcl/visualization/impl/pcl_visualizer.hpp
index a734a357548..263f15b8a5c 100644
--- a/visualization/include/pcl/visualization/impl/pcl_visualizer.hpp
+++ b/visualization/include/pcl/visualization/impl/pcl_visualizer.hpp
@@ -843,6 +843,13 @@ pcl::visualization::PCLVisualizer::addPointCloudNormals (
     PCL_ERROR ("[addPointCloudNormals] The number of points differs from the number of normals!\n");
     return (false);
   }
+
+  if (normals->empty ())
+  {
+    PCL_WARN ("[addPointCloudNormals] An empty normal cloud is given! Nothing to display.\n");
+    return (false);
+  }
+
   if (contains (id))
   {
     PCL_WARN ("[addPointCloudNormals] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());