From b62c7b30ef1d14de423f70f04e89aba7db8f770b Mon Sep 17 00:00:00 2001
From: Matthias Hochsteger <mhochsteger@cerbsim.com>
Date: Tue, 26 Apr 2022 18:44:11 +0200
Subject: [PATCH] DLL_HEADER for fieldline code

---
 libsrc/visualization/fieldlines.cpp |  1 +
 libsrc/visualization/fieldlines.hpp | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/libsrc/visualization/fieldlines.cpp b/libsrc/visualization/fieldlines.cpp
index 44588632..0db30a6e 100644
--- a/libsrc/visualization/fieldlines.cpp
+++ b/libsrc/visualization/fieldlines.cpp
@@ -280,6 +280,7 @@ namespace netgen
   }
   
 
+  FieldLineCalc :: ~FieldLineCalc() {;}
 
   
   void FieldLineCalc :: Calc(const Point<3> & startpoint, Array<Point<3>> & points, Array<double> & vals, Array<bool> & drawelems, Array<int> & dirstart)
diff --git a/libsrc/visualization/fieldlines.hpp b/libsrc/visualization/fieldlines.hpp
index ac3d9fae..06b1f482 100644
--- a/libsrc/visualization/fieldlines.hpp
+++ b/libsrc/visualization/fieldlines.hpp
@@ -32,7 +32,7 @@ private:
 
 public:
 
-  ~RKStepper();
+  DLL_HEADER ~RKStepper();
 
   RKStepper(int type = 0);
 
@@ -77,18 +77,20 @@ private:
   double thickness;
 
 public:
-  FieldLineCalc(const Mesh & amesh, const VectorFunction & afunc,
+  DLL_HEADER FieldLineCalc(const Mesh & amesh, const VectorFunction & afunc,
 		const double rel_length, const int amaxpoints = -1,
 		const double rel_thickness = -1, const double rel_tolerance = -1, const int rk_type = 0, const int adirection = 0);
 
+  DLL_HEADER ~FieldLineCalc();
+
   void SetCriticalValue(const double val) { critical_value = val; }
 
   void Randomized(void) { randomized = true; }
   void NotRandomized(void) { randomized = false; }
 
-  void Calc(const Point<3> & startpoint, Array<Point<3>> & points, Array<double> & vals, Array<bool> & drawelems, Array<int> & dirstart);
+  DLL_HEADER void Calc(const Point<3> & startpoint, Array<Point<3>> & points, Array<double> & vals, Array<bool> & drawelems, Array<int> & dirstart);
 
-  void GenerateFieldLines(Array<Point<3>> & potential_startpoints, const int numlines);
+  DLL_HEADER void GenerateFieldLines(Array<Point<3>> & potential_startpoints, const int numlines);
 
   const auto & GetPStart() const { return pstart; }
   const auto & GetPEnd() const { return pend; }