From 3be02fac7dcfac3989a0b320b8298853e26e4e19 Mon Sep 17 00:00:00 2001
From: Andras Lasso <lasso@queensu.ca>
Date: Wed, 22 May 2024 10:42:54 -0400
Subject: [PATCH] BUG: Fix export of VTK unstructured grid

Mesh type hint was not copied. Node export makes a copy of the node before saving and it did not get the right mesh type hint,
which made saving of unstructured grid mesh saving fail.

Fixes the issue reported at https://discourse.slicer.org/t/error-when-exporting-3d-mesh-model-to-vtu-file-and-invisible-vtk-file-in-paraview/25150
---
 Libs/MRML/Core/vtkMRMLModelNode.cxx | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Libs/MRML/Core/vtkMRMLModelNode.cxx b/Libs/MRML/Core/vtkMRMLModelNode.cxx
index a3a87f71903..bc6872d75f3 100644
--- a/Libs/MRML/Core/vtkMRMLModelNode.cxx
+++ b/Libs/MRML/Core/vtkMRMLModelNode.cxx
@@ -82,6 +82,7 @@ void vtkMRMLModelNode::CopyContent(vtkMRMLNode* anode, bool deepCopy/*=true*/)
   {
     return;
   }
+  this->MeshType = node->MeshType;
   if (deepCopy)
   {
     if (node->GetMesh())