Ellipsoid Meshing Issue in C++

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Hello,

I have Netgen5.3 installed in my PC, the netgen GUI program can mesh the ellipsoid.geo file quickly. Recently, I have tried to call the nglib::Ng_CSG_GenerateMesh() function in C++.

#include <iostream>
#include <fstream>

namespace nglib {
#include <nglib.h>
}

int main(int argc, char** argv)
{
	using namespace nglib;

	char file_name[256];
	strcpy(file_name, argv[1]);
	std::cout << file_name << std::endl;

	// Initialise the Netgen Core library
	nglib::Ng_Init();

	long nvertices = 0;
	long ntriangles = 0;
	long ntetrahedrons = 0;
	double* vertexlist = NULL;
	int* trianglelist = NULL;
	int* tetralist = NULL;
	nglib::Ng_CSG_GenerateMesh(file_name, &nvertices, &ntriangles, &ntetrahedrons, vertexlist, trianglelist, tetralist);
	
	// deconstruct Netgen library.
	nglib::Ng_Exit();

	return 0;
}

DLL_HEADER Ng_Result Ng_CSG_GenerateMesh (const char * filename, long *nvertices, long *ntriangles, long *ntetrahedrons, double * vertexlist, int * trianglelist, int * tetralist);

This code works fine with all the tutorials .geo files in the tutorials directory except the ellipsoid.geo file.

#
## An elliptic cylinder
#
algebraic3d

solid test = ellipsoid (0, 0, 0; 2, 0, 0; 0, 1, 0; 0, 0, 1) -maxh=0.5;

tlo test;

It takes a very long time to mesh and prints a lot of messages:

define solid test
 Calc Triangle Approximation
 Object 0 has 882 triangles
 Start Findpoints
 main-solids: 1
 Found points 0
 Analyze spec points
 done
 find points done
 Find edges
 Add line segment to smooth surface
 0 edges found
 Check intersecting edges
 CalcLocalH: 2 Points 0 Elements 0 Surface Elements
 Start Findpoints
 main-solids: 1
 Found points 0
 Analyze spec points
 done
 Find edges
 Add line segment to smooth surface
 0 edges found
 Check intersecting edges
 Start Findpoints
 main-solids: 1
 Found points 0
 Analyze spec points
 done
 Find edges
 Add line segment to smooth surface
 0 edges found
 Check intersecting edges
 Surface 1 / 1
load internal triangle rules
[b]faces = 66 trials = 1000 elements = 65 els/sec = 650000
faces = 113 trials = 2000 elements = 111 els/sec = 1.11e+06
faces = 141 trials = 3000 elements = 139 els/sec = 1.39e+06
faces = 174 trials = 4000 elements = 172 els/sec = 1.72e+06[/b]
........

I wonder if I need to set the Ng_Meshing_Parameters before meshing ellipsoid object?

Could someone give me a tip on how to generate ellipsoid object mesh correctly.

Thank you.
Wei