OBJ 文件在面值中出现击穿错误

我正在尝试理解一个obj文件，以便我可以将其分解以进行导入。 现在，我的示例是一个简单的金字塔，使用3ds max设计。教程出现了一些小错误。

到目前为止，我理解了一点，但这些加载正常：

v is vertex(point in space),  
vn is vertex normal(don't understand why needed) but imported ok
vt is vertex texture

但文件中的下一个是 F & S，如下所示：

s 4
f 1/1/1 2/2/1 3/3/1 
s 2
f 1/1/2 3/4/2 4/5/2 

首先，我真的不明白s是什么以及为什么它会呈指数级增长？

更重要的是，我没有得到f的细分，根据wikki：

f v1/vt1/vn1  

对我来说，这看起来像v1是顶点，vt是纹理，vn是正常的，但为什么他们会在文件中重复呢？所以我认为我的猜测是错误的。

总的来说，我的

问题是我的加载对象能够填充除面之外的所有内容，除非面与文件底部的多边形相同，然后为 0，但这也没有意义！

请解决我的困惑，谢谢！

这是代码和文件：

[代码]

    public static ObjVolume LoadFromString(string obj)
    {


        // Seperate lines from the file
        List<String> lines = new List<string>(obj.Split(''n'));
        // Lists to hold model data
        List<Vector3> verts = new List<Vector3>();
        List<Vector3> colors = new List<Vector3>();
        List<Vector2> texs = new List<Vector2>();
        List<Tuple<int, int, int>> faces = new List<Tuple<int, int, int>>();
        // Read file line by line
        foreach (String line in lines)
        {
            if (line.StartsWith("v ")) // Vertex definition
            {
                // Cut off beginning of line
                String temp = line.Substring(2);
                temp.TrimStart( );
                Vector3 vec = new Vector3();
                if (temp.Count((char c) => c == ' ') == 3) // Check if there's enough elements for a vertex
                {
                    String[] vertparts = temp.Split(' ');
                    vertparts[3].Replace("'r","");
                    // Attempt to parse each part of the vertice
                    bool success = float.TryParse(vertparts[1], out vec.X);
                    success |= float.TryParse(vertparts[2], out vec.Y);
                    success |= float.TryParse(vertparts[3], out vec.Z);
                    // Dummy color/texture coordinates for now
                    colors.Add(new Vector3((float)Math.Sin(vec.Z), (float)Math.Sin(vec.Z), (float)Math.Sin(vec.Z)));
                    texs.Add(new Vector2((float)Math.Sin(vec.Z), (float)Math.Sin(vec.Z)));
                    // If any of the parses failed, report the error
                    if (!success)
                    {
                        Console.WriteLine("Error parsing vertex: {0}", line);
                    }
                }
                verts.Add(vec);
            }
            else if (line.StartsWith("f ")) // Face definition
            {
                // Cut off beginning of line
                String temp = line.Substring(2);
                Tuple<int, int, int> face = new Tuple<int, int, int>(0, 0, 0);
                if (temp.Count((char c) => c == ' ') == 3) // Check if there's enough elements for a face
                {
                    String[] faceparts = temp.Split(' ');
                    int i1, i2, i3;


                    // Attempt to parse each part of the face
                    bool success = int.TryParse(faceparts[0], out i1);
                    success |= int.TryParse(faceparts[1], out i2);
                    success |= int.TryParse(faceparts[2], out i3); 
                    // If any of the parses failed, report the error
                    if (!success)
                    {
                        Console.WriteLine("Error parsing face: {0}", line);
                    }
                    else
                    {
                        // Decrement to get zero-based vertex numbers
                        face = new Tuple<int, int, int>(i1 - 1, i2 - 1, i3 - 1);
                        faces.Add(face);
                    }
                }
            }
        }
        // Create the ObjVolume
        ObjVolume vol = new ObjVolume();
        vol.vertices = verts.ToArray();
        vol.faces = new List<Tuple<int, int, int>>(faces);
        vol.colors = colors.ToArray();
        vol.texturecoords = texs.ToArray();
        return vol;
    }

# 3ds Max Wavefront OBJ Exporter v0.97b - (c)2007 guruware
# File Created: 27.02.2016 07:40:58
mtllib test1.mtl
#
# object Pyramid001
#
v  -15.7732 14.1346 5.0964
v  -23.0566 0.0050 13.3650
v  -8.4899 0.0050 13.3650
v  -8.4899 0.0050 -3.1722
v  -23.0566 0.0050 -3.1722
v  -15.7732 0.0050 5.0964
# 6 vertices
vn 0.0000 0.5051 0.8631
vn 0.8889 0.4582 -0.0000
vn 0.0000 0.5051 -0.8631
vn -0.8889 0.4582 -0.0000
vn 0.0000 -1.0000 -0.0000
# 5 vertex normals
vt 0.5000 1.0000 0.0000
vt 0.0000 0.0000 0.0000
vt 1.0000 0.0000 0.0000
vt 0.0596 0.0000 0.0000
vt 1.0596 0.0000 0.0000
vt 0.0000 1.0000 0.0000
vt 0.5000 0.5000 0.0000
vt 1.0000 1.0000 0.0000
# 8 texture coords
g Pyramid001
usemtl wire_154215229
s 4
f 1/1/1 2/2/1 3/3/1 
s 2
f 1/1/2 3/4/2 4/5/2 
s 16
f 1/1/3 4/2/3 5/3/3 
s 32
f 1/1/4 5/4/4 2/5/4 
s 8
f 2/6/5 6/7/5 3/8/5 
f 3/8/5 6/7/5 4/3/5 
f 4/3/5 6/7/5 5/2/5 
f 5/2/5 6/7/5 2/6/5 
# 0 polygons - 8 triangles

[/代码]