From e659ad0deb264135fd2117aa39c8df227237bbf0 Mon Sep 17 00:00:00 2001
From: Jonathan <jonathan@skyspecs.com>
Date: Mon, 22 Apr 2024 13:46:19 -0400
Subject: [PATCH] Added support for empty messages (#960)

* Added support for empty messages

* Format
---
 plotjuggler_plugins/PluginsZcm/dataload_zcm.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/plotjuggler_plugins/PluginsZcm/dataload_zcm.cpp b/plotjuggler_plugins/PluginsZcm/dataload_zcm.cpp
index 8abaa9d63..9cfd44342 100644
--- a/plotjuggler_plugins/PluginsZcm/dataload_zcm.cpp
+++ b/plotjuggler_plugins/PluginsZcm/dataload_zcm.cpp
@@ -275,6 +275,15 @@ bool DataLoadZcm::readDataFromFile(FileLoadInfo* info, PlotDataMapRef& plot_data
       return;
     }
 
+    if (evt->datalen == 0)
+    {
+      auto itr = plot_data.numeric.find(evt->channel);
+      if (itr == plot_data.numeric.end())
+        itr = plot_data.addNumeric(evt->channel);
+      itr->second.pushBack({ (double)evt->timestamp / 1e6, 0 });
+      return;
+    }
+
     zcm::Introspection::processEncodedType(evt->channel, evt->data, evt->datalen, "/",
                                            types, processData, &usr);
     for (auto& n : usr.numerics)