Color not appearing on created mesh? (only grey)

Hi,

The color on a dynamically created mesh does not show up, the mesh stays grey. The triangles appear well on the mesh, the Regenerate button works also, but still no color on the mesh. I put the texture in a "Textures" folder, or in "Resources", I changed the vertices to get a 2*2 square, I changed the resolution of each tile, the logs appear well. Sometimes the mesh is black after "regenerate", and saving the project makes it appear grey... I restarted Unity in case it was a bug, but it is still the same. The material for the mesh is Diffuse. Would you know how to debug this?

Here is the code if this can help:

the "Regenerate" button :

 using UnityEditor;
 using UnityEngine;
 using System.Collections;
 
 [CustomEditor(typeof(TileMapNe))]
 public class TileMapInspector : Editor {
     
     public override void OnInspectorGUI() {
         //base.OnInspectorGUI();
         DrawDefaultInspector();
         
         if(GUILayout.Button("Regenerate")) {
             TileMapNe tileMap = (TileMapNe)target;
             tileMap.BuildMesh();
         }
     }
 }
 

The code to create the mesh :

 using UnityEngine;
 using System.Collections;
 
 [ExecuteInEditMode]
 [RequireComponent(typeof(MeshFilter))]
 [RequireComponent(typeof(MeshRenderer))]
 [RequireComponent(typeof(MeshCollider))]
 public class TileMapNe : MonoBehaviour {
     
     public int size_x = 2;
     public int size_z = 2;
     public float tileSize = 15.0f;
     
     public Texture2D terrainTiles;
     public int tileResolution;
     
     
     void Start () {
         BuildMesh();
     }
     
     void BuildTexture() {
         
         int texWidth = size_x * tileResolution;
         int texHeight = size_z * tileResolution;
         Texture2D texture = new Texture2D(texWidth, texHeight);
         
         for(int y=0; y < size_z; y++) {
             for(int x=0; x < size_x; x++) {
                 Color p = new Color(1.0f, 0, 0);
                 texture.SetPixel(x, y, p);
             }
         }
         
         texture.filterMode = FilterMode.Point;
         texture.wrapMode = TextureWrapMode.Clamp;
         texture.Apply();
         
         MeshRenderer mesh_renderer = GetComponent<MeshRenderer>();
         mesh_renderer.sharedMaterials[0].mainTexture = texture;
         
         Debug.Log ("Done Texture!");
     }
     
     public void BuildMesh() {
         int numTiles = size_x * size_z;
         int numTris = numTiles * 2;
         
         int vsize_x = size_x + 1;
         int vsize_z = size_z + 1;
         int numVerts = vsize_x * vsize_z;
         
         // Generate the mesh data
         Vector3[] vertices = new Vector3[ numVerts ];
         Vector3[] normals = new Vector3[numVerts];
         Vector2[] uv = new Vector2[numVerts];
         
         int[] triangles = new int[ numTris * 3 ];
 
         int x, z;
         for(z=0; z < vsize_z; z++) {
             for(x=0; x < vsize_x; x++) {
                 vertices[ z * vsize_x + x ] = new Vector3( x*tileSize, 0, -z*tileSize );
                 normals[ z * vsize_x + x ] = Vector3.up;
                 uv[ z * vsize_x + x ] = new Vector2( (float)x / size_x, 1f - (float)z / size_z );
             }
         }
         Debug.Log ("Done Verts!");
         
         for(z=0; z < size_z; z++) {
             for(x=0; x < size_x; x++) {
                 int squareIndex = z * size_x + x;
                 int triOffset = squareIndex * 6;
                 triangles[triOffset + 0] = z * vsize_x + x +            0;
                 triangles[triOffset + 1] = z * vsize_x + x + vsize_x + 1;
                 triangles[triOffset + 2] = z * vsize_x + x + vsize_x + 0;
                 
                 triangles[triOffset + 3] = z * vsize_x + x +            0;
                 triangles[triOffset + 4] = z * vsize_x + x +            1;
                 triangles[triOffset + 5] = z * vsize_x + x + vsize_x + 1;
             }
         }
         
         Debug.Log ("Done Triangles!");
         
         // Create a new Mesh and populate with the data
         Mesh mesh = new Mesh();
         mesh.vertices = vertices;
         mesh.triangles = triangles;
         mesh.normals = normals;
         mesh.uv = uv;
         
         // Assign our mesh to our filter/renderer/collider
         MeshFilter mesh_filter = GetComponent<MeshFilter>();
         MeshCollider mesh_collider = GetComponent<MeshCollider>();
         
         mesh_filter.mesh = mesh;
         mesh_collider.sharedMesh = mesh;
         Debug.Log ("Done Mesh!");
         
         BuildTexture();
     }
     
 }

Thanks