Export Unity mesh to OBJ or FBX format

Hi,

I would like to export an Unity object (viewed in the scene) to an OBJ or FBX file format object.
Could I do that easily ?

Is there an Asset for that ?

Thanks a lot.
Joe.

 

http://wiki.unity3d.com/index.php?title=ObjExporter

 

Deprected

 

This looks good, and free:
Scene OBJ Exporter
https://www.assetstore.unity3d.com/en/#!/content/22250

 

for fbx,
https://www.assetstore.unity3d.com/en/#!/content/101408

* new link https://assetstore.unity.com/packages/essentials/fbx-exporter-101408
** newer link https://docs.unity3d.com/Packages/com.unity.formats.fbx@2.0/manual/index.html

 

Thanks @mgear

 

Just for the record, Unity now has a FBX exporter as package:
https://docs.unity3d.com/Packages/com.unity.formats.fbx@2.0/manual/index.html

 

Yeah, that's the one mgear linked to above. It was on the asset store, now its a package.

 

I just used ObjExporter.cs and it works fine with changing one line. It will tell you it's deprecated but all you have to change is

Code (CSharp):

1. Material[] mats = mf.renderer.sharedMaterials;

to

Code (CSharp):

1. Material[] mats = mf.GetComponent<Renderer>().sharedMaterials;

 

@hugogfadams Thank you for that update.

 

Thanks! As an additional note, you must turn on "View Preview Packages" to download.

 

Something really beneficial for you all to know.
You can make your own obj. Its just a text file. No need for 3rd party applications and this gives you full control over your export.

• v is your vertices(1 line per vert)

• vn is your normals (1 face per line)

• vt is your uvs (1 uv per line)

• f is your faces, and is split into a triplet of numbers, the first being the vertex index, the second being the uv (vt) index and the third your normal index.

https://en.wikipedia.org/wiki/Wavefront_.obj_file

An example of a properly formatted .obj file:

Code (CSharp):

1. # Creator Name
2. # Creator Website
3. o NameOfObject
4. v -1.000000 0.000000 1.000000
5. v 1.000000 0.000000 1.000000
6. v -1.000000 0.000000 -1.000000
7. v 1.000000 0.000000 -1.000000
8. vn -0.0000 1.0000 -0.0000
9. vt 0.000000 0.000000
10. vt 1.000000 0.000000
11. vt 0.000000 1.000000
12. vt 1.000000 1.000000
13. s 0
14. f 1/1/1 2/2/1 4/4/1 3/3/1

Cheers

 

In case anyone needs it, I wrote a script that export as OBJ.

Code (CSharp):

1. using UnityEngine;
2. using UnityEditor;
3. using System.Collections;
4. using System.IO;
5. using System.Text;
6.  
7. public class ExportMeshToOBJ : ScriptableObject
8. {
9.     [MenuItem("GameObject/Export to OBJ")]
10.     static void ExportToOBJ()
11.     {
12.         GameObject obj = Selection.activeObject as GameObject;
13.         if (obj == null)
14.         {
15.             Debug.Log("No object selected.");
16.             return;
17.         }
18.  
19.         MeshFilter meshFilter = obj.GetComponent<MeshFilter>();
20.         if (meshFilter == null)
21.         {
22.             Debug.Log("No mesh found in selected GameObject.");
23.             return;
24.         }
25.  
26.         string path = EditorUtility.SaveFilePanel("Export OBJ", "", obj.name, "obj");
27.         Mesh mesh = meshFilter.sharedMesh;
28.         StringBuilder sb = new StringBuilder();
29.  
30.         foreach(Vector3 v in mesh.vertices)
31.         {
32.             sb.Append(string.Format("v {0} {1} {2}\n", v.x, v.y, v.z));
33.         }
34.         foreach(Vector3 v in mesh.normals)
35.         {
36.             sb.Append(string.Format("vn {0} {1} {2}\n", v.x, v.y, v.z));
37.         }
38.         for (int material=0; material < mesh.subMeshCount; material++)
39.         {
40.             sb.Append(string.Format("\ng {0}\n", obj.name));
41.             int[] triangles = mesh.GetTriangles(material);
42.             for (int i = 0; i < triangles.Length; i += 3)
43.             {
44.                 sb.Append(string.Format("f {0}/{0} {1}/{1} {2}/{2}\n",
45.                 triangles[i] + 1,
46.                 triangles[i + 1] + 1,
47.                 triangles[i + 2] + 1));
48.             }
49.         }
50.         StreamWriter writer = new StreamWriter(path);
51.         writer.Write(sb.ToString());
52.         writer.Close();
53.     }
54. }
55.  

 

Here's the modified version of the code that supports multiple selection if anyone need it

Code (CSharp):

1. using UnityEngine;
2. using UnityEditor;
3. using System.IO;
4. using System.Text;
5.  
6. public class ExportMeshToOBJ : ScriptableObject
7. {
8.     [MenuItem("GameObject/Export to OBJ")]
9.     static void ExportToOBJ()
10.     {
11.         GameObject obj = Selection.activeObject as GameObject;
12.         if (obj == null)
13.         {
14.             Debug.Log("No object selected.");
15.             return;
16.         }
17.  
18.         MeshFilter meshFilter = obj.GetComponent<MeshFilter>();
19.         if (meshFilter == null)
20.         {
21.             Debug.Log("No MeshFilter is found in selected GameObject.", obj);
22.             return;
23.         }
24.  
25.         if (meshFilter.sharedMesh == null)
26.         {
27.             Debug.Log("No mesh is found in selected GameObject.", obj);
28.             return;
29.         }
30.  
31.         string path = EditorUtility.SaveFilePanel("Export OBJ", "", obj.name, "obj");
32.         StreamWriter writer = new StreamWriter(path);
33.         writer.Write(GetMeshOBJ(obj.name, meshFilter.sharedMesh));
34.         writer.Close();
35.     }
36.  
37.     [MenuItem("GameObject/Export to OBJs")]
38.     static void ExportToOBJs()
39.     {
40.         var objs = Selection.gameObjects;
41.         if (objs.Length < 1)
42.         {
43.             Debug.Log("No object selected.");
44.             return;
45.         }
46.         var directory = EditorUtility.SaveFolderPanel("Export OBJs to", "", "OBJFiles");
47.         foreach (var obj in objs)
48.         {
49.             MeshFilter meshFilter = obj.GetComponent<MeshFilter>();
50.             if (meshFilter == null)
51.             {
52.                 Debug.LogWarning($"No MeshFilter is found in selected GameObject: {obj.name}", obj);
53.                 continue;
54.             }
55.  
56.             if(meshFilter.sharedMesh == null)
57.             {
58.                 Debug.LogWarning($"No mesh is found in selected GameObject: {obj.name}", obj);
59.                 continue;
60.             }
61.  
62.             string path = Path.Combine(directory, obj.name + ".obj");
63.             StreamWriter writer = new StreamWriter(path);
64.             writer.Write(GetMeshOBJ(obj.name, meshFilter.sharedMesh));
65.             writer.Close();
66.         }
67.     }
68.  
69.     public static string GetMeshOBJ(string name, Mesh mesh)
70.     {
71.         StringBuilder sb = new StringBuilder();
72.  
73.         foreach (Vector3 v in mesh.vertices)
74.             sb.Append(string.Format("v {0} {1} {2}\n", v.x, v.y, v.z));
75.  
76.         foreach (Vector3 v in mesh.normals)
77.             sb.Append(string.Format("vn {0} {1} {2}\n", v.x, v.y, v.z));
78.  
79.         for (int material = 0; material < mesh.subMeshCount; material++)
80.         {
81.             sb.Append(string.Format("\ng {0}\n", name));
82.             int[] triangles = mesh.GetTriangles(material);
83.             for (int i = 0; i < triangles.Length; i += 3)
84.             {
85.                 sb.Append(string.Format("f {0}/{0} {1}/{1} {2}/{2}\n",
86.                 triangles[i] + 1,
87.                 triangles[i + 1] + 1,
88.                 triangles[i + 2] + 1));
89.             }
90.         }
91.  
92.         return sb.ToString();
93.     }
94. }

 

If you were wondering why the OBJ's didn't import or you always got a messed up model that is useless this may happen due to your system locale (mine is set to Turkish, which formats floats with ',' character, OBJ format expects '.').
I modified the multi export script so that it always exports correctly independent of system locale (sets the current threads locale as Invariant and resets it back to previous one after exporting, i also added a feature where you can apply Transform Matrix transformations to the meshes, useful if you are exporting a prefab)

Code (CSharp):

1. using UnityEngine;
2. using UnityEditor;
3. using System.IO;
4. using System.Text;
5. using System.Threading;
6. using System.Globalization;
7.  
8. public static class ExportMeshToOBJ
9. {
10.     /// <summary>
11.     /// Whether to apply matrix transformations while exporting a GameObject to OBJ.
12.     /// </summary>
13.     public static bool ApplyObjTransformations = true;
14.  
15.     private static void ExportToObjImpl(GameObject obj, string writePath)
16.     {
17.         if (obj == null)
18.         {
19.             Debug.Log("No object selected.");
20.             return;
21.         }
22.  
23.         if (!obj.TryGetComponent(out MeshFilter meshFilter))
24.         {
25.             Debug.Log("No MeshFilter is found in selected GameObject.", obj);
26.             return;
27.         }
28.  
29.         if (meshFilter.sharedMesh == null)
30.         {
31.             Debug.Log("No mesh is found in selected GameObject.", obj);
32.             return;
33.         }
34.  
35.         CultureInfo previousCurrentCulture = Thread.CurrentThread.CurrentCulture;
36.  
37.         try
38.         {
39.             using StreamWriter writer = new StreamWriter(writePath);
40.  
41.             // Set the culture to always being invariant/standard
42.             // this is why the OBJ's were messed up, my CultureInfo formats floats with ',' instead of '.' which is what OBJ uses.
43.             Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
44.             writer.Write(GetMeshOBJ(obj.name, meshFilter.sharedMesh, ApplyObjTransformations ? obj.transform.localToWorldMatrix : Matrix4x4.identity));
45.         }
46.         catch (System.Exception e)
47.         {
48.             Debug.LogWarning($"[ExportToObjImpl] An exception occured while exporting selected GameObject : {e.Message}\n{e.StackTrace}", obj);
49.         }
50.  
51.         Thread.CurrentThread.CurrentCulture = previousCurrentCulture;
52.     }
53.     public static string GetMeshOBJ(string name, Mesh mesh, Matrix4x4 objTransform)
54.     {
55.         StringBuilder sb = new StringBuilder();
56.  
57.         foreach (Vector3 v in mesh.vertices)
58.         {
59.             Vector3 writeV = (objTransform != Matrix4x4.identity && objTransform != default) ? objTransform.MultiplyPoint(v) : v;
60.             sb.Append(string.Format("v {0} {1} {2}\n", writeV.x, writeV.y, writeV.z));
61.         }
62.  
63.         // Also export UV's
64.         foreach (Vector3 v in mesh.uv)
65.         {
66.             sb.Append(string.Format("vt {0} {1} {2}\n", v.x, v.y, v.z));
67.         }
68.  
69.         foreach (Vector3 v in mesh.normals)
70.         {
71.             sb.Append(string.Format("vn {0} {1} {2}\n", v.x, v.y, v.z));
72.         }
73.  
74.         for (int material = 0; material < mesh.subMeshCount; material++)
75.         {
76.             sb.Append(string.Format("\ng {0}\n", name));
77.             int[] triangles = mesh.GetTriangles(material);
78.             for (int i = 0; i < triangles.Length; i += 3)
79.             {
80.                 sb.Append(string.Format("f {0}/{0} {1}/{1} {2}/{2}\n",
81.                 triangles[i] + 1,
82.                 triangles[i + 1] + 1,
83.                 triangles[i + 2] + 1));
84.             }
85.         }
86.  
87.         return sb.ToString();
88.     }
89.  
90.     private static string PreviousSelectedDirectory = "";
91.  
92.     [MenuItem("GameObject/Export to OBJ")]
93.     static void ExportToOBJ()
94.     {
95.         ApplyObjTransformations = false;
96.  
97.         GameObject obj = Selection.activeObject as GameObject;
98.         string path = EditorUtility.SaveFilePanel("Export OBJ", PreviousSelectedDirectory, obj.name, "obj");
99.  
100.         ExportToObjImpl(obj, path);
101.     }
102.     [MenuItem("GameObject/Export to OBJs")]
103.     static void ExportToOBJs()
104.     {
105.         ApplyObjTransformations = false;
106.  
107.         GameObject[] objs = Selection.gameObjects;
108.         if (objs.Length < 1)
109.         {
110.             Debug.Log("No object selected.");
111.             return;
112.         }
113.         string directory = EditorUtility.SaveFolderPanel("Export OBJs to", PreviousSelectedDirectory, "OBJFiles");
114.         PreviousSelectedDirectory = directory;
115.  
116.         foreach (GameObject obj in objs)
117.         {
118.             ExportToObjImpl(obj, Path.Combine(directory, obj.name + ".obj"));
119.         }
120.     }
121.  
122.     [MenuItem("GameObject/Export to OBJ (Apply GameObject Transform)")]
123.     static void ExportToOBJWithTransformations()
124.     {
125.         ApplyObjTransformations = true;
126.  
127.         GameObject obj = Selection.activeObject as GameObject;
128.         string path = EditorUtility.SaveFilePanel("Export OBJ", PreviousSelectedDirectory, obj.name, "obj");
129.  
130.         ExportToObjImpl(obj, path);
131.     }
132.     [MenuItem("GameObject/Export to OBJs (Apply GameObject Transform)")]
133.     static void ExportToOBJsWithTransformations()
134.     {
135.         ApplyObjTransformations = true;
136.  
137.         GameObject[] objs = Selection.gameObjects;
138.         if (objs.Length < 1)
139.         {
140.             Debug.Log("No object selected.");
141.             return;
142.         }
143.         string directory = EditorUtility.SaveFolderPanel("Export OBJs to", PreviousSelectedDirectory, "OBJFiles");
144.         PreviousSelectedDirectory = directory;
145.  
146.         foreach (GameObject obj in objs)
147.         {
148.             ExportToObjImpl(obj, Path.Combine(directory, obj.name + ".obj"));
149.         }
150.     }
151. }
152.