class Program
{
    private static float[] vert = new float[]{  0,0,0,
                                                1,0,0,
                                                1,1,0,
                                                0,1,0};//v
    private static float[] normals = new float[]{1,1,1,
                                                1,1,1,
                                                1,1,1,
                                                1,1,1};//vn
    private static AttributeData[] uvad = { new AttributeData ("uv1", "test",
                                                                AttributeData.STANDARD_UV_PRECISION,
                                                                new float[]{0.0034f, 0.1f,
                                                                            0.8f, 1.0f,
                                                                            0.351f, 0.612f,
                                                                            0.1229f, 0.91224f}) };//vt
    private static int[] ind = new int[] { 0, 1, 2, 0, 2, 3 };//f
    private static Mesh quad = new Mesh(vert, normals, ind, uvad, new AttributeData[0]);
    
    
    public void rawTest()
    {
        testEncoder(new RawEncoder());
    }

    public void mg1Test()
    {
        testEncoder(new MG1Encoder());
    }

    public void mg2Test()
    {
        testEncoder(new MG2Encoder(MG2Encoder.STANDARD_VERTEX_PRECISION, MG2Encoder.STANDARD_NORMAL_PRECISION));
    }

    private void testEncoder(MeshEncoder encoder)
    {
        MemoryStream memory = new MemoryStream();
        CtmFileWriter writer = new CtmFileWriter(memory, encoder);
        writer.encode(quad, null);

        memory.Seek(0, SeekOrigin.Begin);
        using (FileStream file = new FileStream("mayu.ctm", FileMode.Create, System.IO.FileAccess.Write))
            memory.CopyTo(file);
        Stream readMemory = new MemoryStream(memory.ToArray());
        CtmFileReader reader = new CtmFileReader(readMemory);
        Mesh m = reader.decode();

        m.checkIntegrity();

        //MG2Encoder mg2 = encoder as MG2Encoder;

        //Chech file integirty
        //MemoryStream ms = new MemoryStream();
        //using (FileStream file = new FileStream("col.ctm", FileMode.Open, FileAccess.Read))
        //    file.CopyTo(ms);

        //Stream readMemory1 = new MemoryStream(ms.ToArray());
        //CtmFileReader reader1 = new CtmFileReader(readMemory1);
        //Mesh m2 = reader1.decode();

        //m2.checkIntegrity();
        //float[] v = m2.vertices;
        //float[] n = m2.normals;
        //AttributeData []ad = m2.texcoordinates;
        //int[] index = m2.indices;
        //var t= m2.getVertexCount();
        //var c = m2.getTriangleCount();

        
    }

    static void Main(string[] args)
    {
        Program p = new ConsoleApplication1.Program();

        var filrread = File.ReadAllLines(@"D:\\collar.obj");
       //var filrread = File.ReadAllLines(@"D:\\Box.obj");
       // var filrread = File.ReadAllLines(@"D:\\boxxxx.obj");

        var ctmName = filrread.Where(x => x.Contains("object")).Select(x => x.Split(' ')[2]).FirstOrDefault();

        var vcount = Convert.ToInt32(filrread.Where(x => x.Contains("vertices")).Select(x => x.Split(' ')[1]).FirstOrDefault())*3;
        var vncount = Convert.ToInt32(filrread.Where(x => x.Contains("normals")).Select(x => x.Split(' ')[1]).FirstOrDefault())*3;
        var vtcount = Convert.ToInt32(filrread.Where(x => x.Contains("texture")).Select(x => x.Split(' ')[1]).FirstOrDefault())*3;

        var fcount = Convert.ToInt32(filrread.Where(x => x.Contains("triangles")).Select(x => x.Split(' ')[4]).FirstOrDefault());

        var v = filrread.Where(x => x.StartsWith("v ")).Select(x => x.Replace("v  ", string.Empty).Split(' ').ToList()).ToList();
        var vn = filrread.Where(x => x.StartsWith("vn ")).Select(x => x.Replace("vn ", string.Empty).Split(' ').ToList()).ToList();
        var vt = filrread.Where(x => x.StartsWith("vt ")).Select(x => x.Replace("vt ", string.Empty).Split(' ').ToList()).ToList();

        var f = filrread.Where(x => x.StartsWith("f ")).Select(x => x.Replace("f ", string.Empty).TrimEnd().Split(' ').ToList().Select(ac => ac.Split('/')[0])).ToList();

        List<float> vertex = new List<float>();
        List<float> normal = new List<float>();
        List<float> uv = new List<float>();
        List<int> index = new List<int>();

        int cnt = 0;
        foreach (var item in v)
        {
            foreach (var itemList in item)
            {
                vertex.Add(Convert.ToSingle(itemList));
                //normal.Add(cnt);
                //uv.Add(cnt);
                //cnt++;
            }
        }

        foreach (var item in vn)
        {
            foreach (var itemList in item)
            {
                normal.Add(Convert.ToSingle(itemList));
            }
        }

        foreach (var item in vt)
        {
            //foreach (var itemList in item)
            for (int i = 0; i < item.Count - 1; i++)
            {
                //uv.Add(Convert.ToSingle(itemList[i]));
                uv.Add(Convert.ToSingle(item[i]));
            }
        }

        foreach (var item in f)
        {
            foreach (var itemList in item)
            {
                index.Add(Convert.ToInt32(itemList)-1);  // remove -1 For Face adjustment
            }
        }

        //if (vertex.Count == vcount && normal.Count == vncount && uv.Count == (vtcount-vt.Count) && f.Count == fcount)
        {

            vert = vertex.ToArray();
            normals = normal.ToArray();
            AttributeData ad = new AttributeData(ctmName, "1", AttributeData.STANDARD_UV_PRECISION, uv.ToArray());
            List<AttributeData> adlist = new List<AttributeData>();
            adlist.Add(ad);
            ind = index.ToArray();

            quad = new Mesh(vert, normals, ind, adlist.ToArray(), new AttributeData[0]);
        }


        p.mg2Test();
    }
}

$ make -f Makefile.linux
$ curl -L -O https://github.com/gazebosim/gazebo-classic/raw/gazebo10_10.1.0/media/models/sitting.dae
$ LD_LIBRARY_PATH="$PWD/lib" ./tools/ctmconv sitting.dae sitting.ctm
Loading sitting.dae... 47.15 ms
Saving sitting.ctm... /usr/include/c++/13/bits/stl_vector.h:1125: std::vector<_Tp, _Alloc>::reference std::vector<_Tp, _Alloc>::operator[](size_type) [with _Tp = int; _Alloc = std::allocator<int>; reference = int&; size_type = long unsigned int]: Assertion '__n < this->size()' failed.
Aborted (core dumped)

$ LD_LIBRARY_PATH="$PWD/lib" gdb --args ./tools/ctmconv sitting.dae sitting.ctm
[…]
(gdb) bt
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
#1  0x00007ffff7aae8a3 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at pthread_kill.c:78
#2  0x00007ffff7a5c8ee in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff7a448ff in __GI_abort () at abort.c:79
#4  0x00007ffff7cd95b0 in std::__glibcxx_assert_fail (file=file@entry=0x4250e8 "/usr/include/c++/13/bits/stl_vector.h", line=line@entry=1125, 
    function=function@entry=0x425110 "std::vector<_Tp, _Alloc>::reference std::vector<_Tp, _Alloc>::operator[](size_type) [with _Tp = int; _Alloc = std::allocator<int>; reference = int&; size_type = long unsigned int]", condition=condition@entry=0x425010 "__n < this->size()") at ../../../../../libstdc++-v3/src/c++11/assert_fail.cc:41
#5  0x00000000004062d9 in std::vector<int, std::allocator<int> >::operator[] (this=this@entry=0x7fffffffd298, __n=__n@entry=0) at /usr/include/c++/13/bits/stl_vector.h:1125
#6  0x0000000000409890 in Export_CTM (aFileName=aFileName@entry=0x7fffffffd340 "sitting.ctm", aMesh=aMesh@entry=0x7fffffffd250, aOptions=...) at ctm.cpp:127
#7  0x000000000040921a in ExportMesh (aFileName=0x7fffffffd340 "sitting.ctm", aMesh=aMesh@entry=0x7fffffffd250, aOptions=...) at meshio.cpp:82
#8  0x0000000000405c64 in main (argc=3, argv=0x7fffffffd538) at /usr/include/c++/13/bits/basic_string.h:222
(gdb) frame 6
#6  0x0000000000409890 in Export_CTM (aFileName=aFileName@entry=0x7fffffffd340 "sitting.ctm", aMesh=aMesh@entry=0x7fffffffd250, aOptions=...) at ctm.cpp:127
127                      (const CTMuint*) &aMesh->mIndices[0], aMesh->mIndices.size() / 3,
 print *aMesh
$2 = {mOriginalNormals = true, mComment = "", mTexFileName = "", mIndices = std::vector of length 0, capacity 0, mVertices = std::vector of length 0, capacity 0, 
  mNormals = std::vector of length 0, capacity 0, mColors = std::vector of length 0, capacity 0, mAttributes = std::vector of length 0, capacity 0, mTexCoords = std::vector of length 0, capacity 0, 
  attributesName = 0x0}

     Mesh mesh = reader.decode();

     FileStream newfs = new FileStream(@".\TestData\raw2gm2.ctm", FileMode.OpenOrCreate);
     CtmFileWriter fw = new CtmFileWriter(newfs, new MG2Encoder());
     fw.encode(mesh, "reproduce error.");
     newfs.Close();

if (strcmp(magic, "ply\n")) {
        fclose(fp);
        error_cb("Not a PLY file. Expected magic number 'ply\\n'");
        return NULL;
    }

ply\r\n
format ascii 1.0\r\n
... ect

$ make -f Makefile.linux
$ curl -L -O https://github.com/mikedh/trimesh/raw/4.2.4/models/headless.ctm
$ LD_LIBRARY_PATH="$PWD/lib" ./tools/ctmconv headless.ctm headless.off
Loading headless.ctm... 3.775 ms
Saving headless.off... 87.118 ms
$ LD_LIBRARY_PATH="$PWD/lib" ./tools/ctmconv headless.off foo.ctm
Loading headless.off... /usr/include/c++/13/bits/basic_string.h:1238: std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::const_reference std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator[](size_type) const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; const_reference = const char&; size_type = long unsigned int]: Assertion '__pos <= size()' failed.
Aborted (core dumped)

$ LD_LIBRARY_PATH="$PWD/lib" gdb --args ./tools/ctmconv headless.off foo.ctm
[…]
(gdb) bt
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
#1  0x00007ffff7aae8a3 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at pthread_kill.c:78
#2  0x00007ffff7a5c8ee in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff7a448ff in __GI_abort () at abort.c:79
#4  0x00007ffff7cd95b0 in std::__glibcxx_assert_fail (file=file@entry=0x4258c0 "/usr/include/c++/13/bits/basic_string.h", line=line@entry=1238,
    function=function@entry=0x4258e8 "std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::const_reference std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::operator[](size_type) const [with _CharT = char; _Traits = std::char_traits<ch"..., condition=condition@entry=0x425798 "__pos <= size()") at ../../../../../libstdc++-v3/src/c++11/assert_fail.cc:41
#5  0x0000000000406ad0 in std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::operator[] (this=this@entry=0x7fffffffcc30, __pos=__pos@entry=18446744073709551615)
    at /usr/include/c++/13/bits/basic_string.h:1238
#6  0x000000000040689b in TrimString (aString="") at common.cpp:48
#7  0x000000000041be16 in ReadNextLine (aStream=..., aResult="OFF", aComment="Binary STL output from Blender: /home/marcus/Projekt/OpenCTM/tools/headlessgiant") at off.cpp:72
#8  0x000000000041c023 in Import_OFF (aFileName=aFileName@entry=0x7fffffffd370 "headless.off", aMesh=aMesh@entry=0x7fffffffd260) at off.cpp:114
#9  0x000000000040907f in ImportMesh (aFileName=0x7fffffffd370 "headless.off", aMesh=aMesh@entry=0x7fffffffd260) at meshio.cpp:68
#10 0x0000000000405b87 in main (argc=3, argv=0x7fffffffd548) at /usr/include/c++/13/bits/basic_string.h:222
(gdb) frame 6
#6  0x000000000040689b in TrimString (aString="") at common.cpp:48
48        while((p2 > p1) && IsWhiteSpace(aString[p2]))
(gdb) info locals
l = <optimized out>
p1 = 0
p2 = 18446744073709551615
(gdb) info args
aString = ""
(gdb) frame 7
#7  0x000000000041be16 in ReadNextLine (aStream=..., aResult="OFF", aComment="Binary STL output from Blender: /home/marcus/Projekt/OpenCTM/tools/headlessgiant") at off.cpp:72
72          aResult = TrimString(line);
(gdb) info locals
line = ""
commentPos = 0