From a42ecab606759e11fc86f57af5ed4379bfc52ac0 Mon Sep 17 00:00:00 2001
From: Philippose Rajan <philippose>
Date: Sun, 15 Feb 2009 20:18:21 +0000
Subject: [PATCH] * Added a new demonstrator program for the nglib library
 which shows how to read in an STL geometry file, initialise the STL geometry,
 mesh it, and save it as a VOL mesh file. * Modified the makefile to include
 the new demo program ng_stl during the Linux compile process

---
 nglib/Makefile.am |   5 +-
 nglib/ng_stl.cpp  | 116 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 120 insertions(+), 1 deletion(-)
 create mode 100644 nglib/ng_stl.cpp

diff --git a/nglib/Makefile.am b/nglib/Makefile.am
index a4eacfc8..21f914fc 100644
--- a/nglib/Makefile.am
+++ b/nglib/Makefile.am
@@ -27,6 +27,9 @@ ng_vol_LDADD = \
 	libnglib.la 
 
 
-
+bin_PROGRAMS = ng_stl
+ng_vol_SOURCES = ng_stl.cpp
+ng_vol_LDADD = \
+	libnglib.la 
 
 
diff --git a/nglib/ng_stl.cpp b/nglib/ng_stl.cpp
new file mode 100644
index 00000000..115b776d
--- /dev/null
+++ b/nglib/ng_stl.cpp
@@ -0,0 +1,116 @@
+/*!
+   \file ng_stl.cpp
+   \author Philippose Rajan
+   \date 14 Feb 2009 (Created)
+
+   This sample utility demonstrates the use of the Netgen 
+   nglib library for reading, and meshing an STL geometry. 
+
+   The Program takes as input the name of an STL file 
+   saved in the STL ASCII Format, and generates a 3D Volume 
+   mesh which is saved into the file "test.vol".
+
+   test.vol can be viewed using the usual Netgen Mesher GUI
+*/
+
+
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+namespace nglib {
+#include <nglib.h>
+}
+
+int main (int argc, char ** argv)
+{
+   using namespace nglib;
+
+   cout << "Netgen (nglib) STL Testing" << endl;
+
+   if (argc < 2)
+   {
+      cerr << "use: ng_stl STL_filename" << endl;
+      return 1;
+   }
+
+   // Define pointer to a new Netgen Mesh
+   Ng_Mesh *mesh;
+   
+   // Define pointer to STL Geometry
+   Ng_STL_Geometry *stl_geom;
+
+   // Result of Netgen Operations
+   Ng_Result ng_res;
+   
+   // Initialise the Netgen Core library
+   Ng_Init();
+
+   // Actually create the mesh structure
+   mesh = Ng_NewMesh();
+
+   int np, ne;
+
+   // Read in the STL File
+   stl_geom = Ng_STL_LoadGeometry(argv[1]);
+   if(!stl_geom)
+   {
+      cout << "Error reading in STL File: " << argv[1] << endl;
+	  return 1;
+   }
+   cout << "Successfully loaded STL File: " << argv[1] << endl;
+
+
+   // Set the Meshing Parameters to be used
+   Ng_Meshing_Parameters mp;
+   mp.maxh = 1.0e+6;
+   mp.fineness = 0.4;
+   mp.secondorder = 0;
+
+   cout << "Initialise the STL Geometry structure...." << endl;
+   ng_res = Ng_STL_InitSTLGeometry(stl_geom);
+   if(ng_res != NG_OK)
+   {
+      cout << "Error Initialising the STL Geometry....Aborting!!" << endl;
+	   return 1;
+   }
+
+   cout << "Start Edge Meshing...." << endl;
+   ng_res = Ng_STL_MakeEdges(stl_geom, mesh, &mp);
+   if(ng_res != NG_OK)
+   {
+      cout << "Error in Edge Meshing....Aborting!!" << endl;
+	   return 1;
+   }
+
+   cout << "Start Surface Meshing...." << endl;
+   ng_res = Ng_STL_GenerateSurfaceMesh(stl_geom, mesh, &mp);
+   if(ng_res != NG_OK)
+   {
+      cout << "Error in Surface Meshing....Aborting!!" << endl;
+	   return 1;
+   }
+   
+   cout << "Start Volume Meshing...." << endl;
+   ng_res = Ng_GenerateVolumeMesh (mesh, &mp);
+   if(ng_res != NG_OK)
+   {
+      cout << "Error in Volume Meshing....Aborting!!" << endl;
+	  return 1;
+   }
+   
+   cout << "Meshing successfully completed....!!" << endl;
+
+   // volume mesh output
+   np = Ng_GetNP(mesh);
+   cout << "Points: " << np << endl;
+
+   ne = Ng_GetNE(mesh);
+   cout << "Elements: " << ne << endl;
+
+   cout << "Saving Mesh in VOL Format...." << endl;
+   Ng_SaveMesh(mesh,"test.vol");
+
+   return 0;
+}