Hi team, I have issue with convert format .obj mesh to speckle, it show me some thing wrong, I hope can hear some assistant idea of team about that :
This is Class read file .obj to speckle mesh
using System;
using System.Collections.Generic;
using System.IO;
namespace ForgeToolkit.WaveFront
{
public class WaveFront
{
public List<MeshGroup> MeshGroups { get; } = new List<MeshGroup>();
public List<Material> Materials { get; } = new List<Material>();
public void Load(string filePath)
{
try
{
// get file mtl inside
string mtlFileName = null;
using (StreamReader reader = new StreamReader(filePath))
{
string line;
while ((line = reader.ReadLine()) != null)
{
line = line.Trim();
if (string.IsNullOrEmpty(line) || line[0] == '#')
continue;
string[] parts = line.Split(' ');
if (parts[0] == "mtllib")
{
// Material library reference
mtlFileName = parts[1];
break;
}
}
}
if (!string.IsNullOrEmpty(mtlFileName))
{
// Load the associated .mtl file
LoadMaterialFile(Path.Combine(Path.GetDirectoryName(filePath), mtlFileName));
}
using (StreamReader reader = new StreamReader(filePath))
{
string line;
MeshGroup currentGroup = null;
Material currentMaterial = null; // Track the current material for assignment
while ((line = reader.ReadLine()) != null)
{
line = line.Trim();
if (string.IsNullOrEmpty(line) || line[0] == '#')
continue;
string[] parts = line.Split(' ');
if (parts[0] == "v")
{
// Vertex line
if (parts.Length >= 4 &&
float.TryParse(parts[1], out float x) &&
float.TryParse(parts[2], out float y) &&
float.TryParse(parts[3], out float z))
{
if (currentGroup != null)
{
currentGroup.Vertices.Add(new Vector3(x, y, z));
}
}
}
else if (parts[0] == "f")
{
// Face line
if (parts.Length >= 4)
{
List<int> vertexIndices = new List<int>();
for (int i = 1; i < parts.Length; i++)
{
string[] vertexInfo = parts[i].Split('/');
if (int.TryParse(vertexInfo[0], out int vertexIndex))
{
vertexIndices.Add(vertexIndex);
}
}
if (vertexIndices.Count >= 3)
{
if (currentGroup != null)
{
currentGroup.Faces.Add(new Face(vertexIndices[0], vertexIndices[1],
vertexIndices[2]));
currentGroup.Material = currentMaterial; // Assign the current material
}
}
}
}
else if (parts[0] == "vc")
{
// Vertex color line (custom extension; adjust this line to match your OBJ format)
if (parts.Length >= 4 &&
float.TryParse(parts[1], out float r) &&
float.TryParse(parts[2], out float g) &&
float.TryParse(parts[3], out float b))
{
if (currentGroup != null)
{
currentGroup.VertexColors.Add(new Color(r, g, b));
}
}
}
else if (parts[0] == "g")
{
// Group statement
string groupName = string.Join(" ", parts, 1, parts.Length - 1).Trim();
currentGroup = new MeshGroup(groupName);
MeshGroups.Add(currentGroup);
currentMaterial = null; // Reset the current material
}
else if (parts[0] == "usemtl")
{
// Use material statement
string materialName = string.Join(" ", parts, 1, parts.Length - 1).Trim();
currentMaterial = Materials.Find(m => m.Name == materialName);
}
}
}
}
catch (Exception ex)
{
Console.WriteLine("Error reading OBJ file: " + ex.Message);
}
}
private void LoadMaterialFile(string mtlFilePath)
{
try
{
using (StreamReader reader = new StreamReader(mtlFilePath))
{
string line;
Material currentMaterial = null;
while ((line = reader.ReadLine()) != null)
{
line = line.Trim();
if (string.IsNullOrEmpty(line) || line[0] == '#')
continue;
string[] parts = line.Split(' ');
if (parts[0] == "newmtl")
{
// New material definition
string materialName = string.Join(" ", parts, 1, parts.Length - 1).Trim();
currentMaterial = new Material(materialName);
Materials.Add(currentMaterial);
}
else if (parts[0] == "Kd" && currentMaterial != null)
{
// Diffuse color (adjust based on your .mtl format)
if (parts.Length >= 4 &&
float.TryParse(parts[1], out float r) &&
float.TryParse(parts[2], out float g) &&
float.TryParse(parts[3], out float b))
{
currentMaterial.Color = new Color(r, g, b);
}
}
// Add more material properties parsing as needed (e.g., specular color, ambient color, etc.)
}
}
}
catch (Exception ex)
{
Console.WriteLine("Error reading .mtl file: " + ex.Message);
}
}
}
public class Vector3
{
public float X { get; }
public float Y { get; }
public float Z { get; }
public Vector3(float x, float y, float z)
{
X = x;
Y = y;
Z = z;
}
}
public class Face
{
public int V1 { get; }
public int V2 { get; }
public int V3 { get; }
public Face(int v1, int v2, int v3)
{
V1 = v1;
V2 = v2;
V3 = v3;
}
}
public class Color
{
public float R { get; }
public float G { get; }
public float B { get; }
public Color(float r, float g, float b)
{
R = r;
G = g;
B = b;
}
}
public class Material
{
public string Name { get; }
public int Id { get; set; }
public Color Color { get; set; } // Adjust based on your .mtl format
public Material(string name)
{
Name = name;
if (name.Contains("."))
{
string[] parts = name.Split('.');
if (parts.Length == 2 && int.TryParse(parts[1], out int id))
{
Id = id;
}
}
else
{
Id = -1;
}
}
}
public class MeshGroup
{
public string Name { get; }
public int Id { get; set; }
public List<Vector3> Vertices { get; } = new List<Vector3>();
public List<Face> Faces { get; } = new List<Face>();
public List<Color> VertexColors { get; } = new List<Color>();
public Material Material { get; set; }
public MeshGroup(string name)
{
Name = name;
if (name.Contains("."))
{
string[] parts = name.Split('.');
if (parts.Length == 2 && int.TryParse(parts[1], out int id))
{
Id = id;
}
}
else
{
Id = -1;
}
}
}
}
And I tried to send it to speckle :
WaveFront waveFront = new WaveFront();
waveFront.Load(objPath);
List<MeshGroup> meshGroups = waveFront.MeshGroups;
Console.WriteLine("Done with ReadTriangles");
List<Mesh> baseMeshes = new List<Mesh>();
foreach (MeshGroup meshGroup in meshGroups)
{
Mesh mesh = MeshGroupToSpeckleMesh(meshGroup);
baseMeshes.Add(mesh);
}
// send list baseMeshes to speckle
Base data = new Base();
data["@baseMeshes"] = baseMeshes;
string streamId = "db5902deb6";
string send = await Helpers.Send(streamId, data, "test obj").ConfigureAwait(false);
Console.WriteLine("Done with Send Data To Speckle");
Objects.Geometry.Mesh MeshGroupToSpeckleMesh(MeshGroup meshGroup)
{
Mesh mesh = new Mesh();
mesh.vertices = meshGroup.Vertices.SelectMany(v => new double[] { v.X, v.Y, v.Z }).ToList();
mesh.faces = meshGroup.Faces.SelectMany(f => new int[] { f.V1, f.V2, f.V3 }).ToList();
mesh.colors = ToSpeckleColor(meshGroup.Material.Color);
mesh.id = meshGroup.Id.ToString();
mesh.units = Units.Feet;
return mesh;
}
List<int> ToSpeckleColor(Color color)
{
int r = (int) color.R;
int g = (int) color.G;
int b = (int) color.B;
return new List<int> { r, g, b, 0 };
}
This is my file sample 
ac734220-e1c3-324f-93df-b5c65ffb2f5e.obj (440.1 KB)
ac734220-e1c3-324f-93df-b5c65ffb2f5e.mtl (770 Bytes)
And this one is how it look like when open use https://3dviewer.net/ :
Any recommend is apprecitated, thank you, my thinking at the first time is it relate to Normals define at vn
