From dd6638b1ab3cbb18eb1198ff0155392336fe2158 Mon Sep 17 00:00:00 2001
From: Matthias Hochsteger <mhochsteger@cerbsim.com>
Date: Fri, 22 Nov 2024 15:39:07 +0100
Subject: [PATCH] Mesh::GetRegionName(element_or_elindex)

---
 libsrc/general/mystring.cpp  | 10 ++++++++++
 libsrc/general/mystring.hpp  |  1 +
 libsrc/meshing/meshclass.cpp | 15 +++++++++++++++
 libsrc/meshing/meshclass.hpp |  8 ++++++++
 4 files changed, 34 insertions(+)

diff --git a/libsrc/general/mystring.cpp b/libsrc/general/mystring.cpp
index cd2ed300..c88cfab3 100644
--- a/libsrc/general/mystring.cpp
+++ b/libsrc/general/mystring.cpp
@@ -223,6 +223,16 @@ MyStr::MyStr(const string & st)
   strcpy (str, st.c_str());
 }
 
+MyStr::MyStr(string_view sv)
+{
+  length = unsigned(sv.length());
+  if (length > SHORTLEN)
+    str = new char[length + 1];
+  else
+    str = shortstr;
+  strcpy (str, sv.data());
+}
+
 MyStr::MyStr(const filesystem::path & path)
     : MyStr(path.string())
 { }
diff --git a/libsrc/general/mystring.hpp b/libsrc/general/mystring.hpp
index ee364d77..4f2167ec 100644
--- a/libsrc/general/mystring.hpp
+++ b/libsrc/general/mystring.hpp
@@ -60,6 +60,7 @@ public:
   MyStr(const Point3d& p);
   MyStr(const Vec3d& p);
   MyStr(const string & st);
+  MyStr(string_view sv);
   MyStr(const filesystem::path & st);
 
   ~MyStr();
diff --git a/libsrc/meshing/meshclass.cpp b/libsrc/meshing/meshclass.cpp
index 00958203..7fa8bfb1 100644
--- a/libsrc/meshing/meshclass.cpp
+++ b/libsrc/meshing/meshclass.cpp
@@ -7528,6 +7528,21 @@ namespace netgen
       }
   }
   
+
+  std::string_view Mesh :: GetRegionName (const Segment & el) const
+  {
+    return *const_cast<Mesh&>(*this).GetRegionNamesCD(GetDimension()-1)[el.edgenr-1];
+  }
+
+  std::string_view Mesh :: GetRegionName (const Element2d & el) const
+  {
+    return *const_cast<Mesh&>(*this).GetRegionNamesCD(GetDimension()-2)[GetFaceDescriptor(el).BCProperty()-1];
+  }
+
+  std::string_view Mesh :: GetRegionName (const Element & el) const
+  {
+    return *const_cast<Mesh&>(*this).GetRegionNamesCD(GetDimension()-3)[el.GetIndex()-1];
+  }
   
 
   void Mesh :: SetUserData(const char * id, NgArray<int> & data)
diff --git a/libsrc/meshing/meshclass.hpp b/libsrc/meshing/meshclass.hpp
index 5d7c7e7a..4be51c87 100644
--- a/libsrc/meshing/meshclass.hpp
+++ b/libsrc/meshing/meshclass.hpp
@@ -749,6 +749,14 @@ namespace netgen
 
 
     DLL_HEADER NgArray<string*> & GetRegionNamesCD (int codim);
+
+    DLL_HEADER std::string_view GetRegionName(const Segment & el) const;
+    DLL_HEADER std::string_view GetRegionName(const Element2d & el) const;
+    DLL_HEADER std::string_view GetRegionName(const Element & el) const;
+
+    std::string_view GetRegionName(SegmentIndex ei) const { return GetRegionName((*this)[ei]); }
+    std::string_view GetRegionName(SurfaceElementIndex ei) const { return GetRegionName((*this)[ei]); }
+    std::string_view GetRegionName(ElementIndex ei) const { return GetRegionName((*this)[ei]); }
     
     ///
     void ClearFaceDescriptors()