From 512f305c12a6977d710b23eb7da620995c4e5aa3 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 3 Jan 2018 00:09:30 +0100
Subject: [PATCH] display: fix assertions when removing window that isn't open
 yet

---
 panda/src/display/graphicsEngine.cxx | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/panda/src/display/graphicsEngine.cxx b/panda/src/display/graphicsEngine.cxx
index eca453900e..e7ea4acd78 100644
--- a/panda/src/display/graphicsEngine.cxx
+++ b/panda/src/display/graphicsEngine.cxx
@@ -529,7 +529,11 @@ remove_window(GraphicsOutput *window) {
   // Also check whether it is in _new_windows.
   {
     MutexHolder new_windows_holder(_new_windows_lock, current_thread);
+    size_t old_size = _new_windows.size();
     _new_windows.erase(std::remove(_new_windows.begin(), _new_windows.end(), ptwin), _new_windows.end());
+    if (count == 0 && _new_windows.size() < old_size) {
+      count = 1;
+    }
   }
 
   if (count == 0) {