From 09188b1a73ce698efad6ca380138fdf493d784aa Mon Sep 17 00:00:00 2001
From: Matthias Hochsteger <mhochsteger@cerbsim.com>
Date: Wed, 7 Sep 2022 13:44:55 +0200
Subject: [PATCH] no edge swapping for quads

---
 libsrc/meshing/improve2.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libsrc/meshing/improve2.cpp b/libsrc/meshing/improve2.cpp
index b215bfd7..c46df8a0 100644
--- a/libsrc/meshing/improve2.cpp
+++ b/libsrc/meshing/improve2.cpp
@@ -339,6 +339,9 @@ namespace netgen
             if (swapped[t1])
               return;
 
+            if(mesh[t1].GetNP() != 3)
+              return;
+
             if (multithread.terminate)
               throw NgException ("Meshing stopped");