How to generate a subdivided plane mesh

Question

Hello. I am trying to make a mesh that displays a grid of 16x16 vertices. I have already been successful at plotting the 256 vertices (I used gizmos to see that they are there). However, I seem to be having trouble with the triangles, which do not connect all of the vertices. Here is the code for my mesh; could someone please tell me what I'm doing wrong? Thanks! :)

     public void RenderMesh()
     {
         var vertices = new List<Vector3>();
         var uvs = new List<Vector2>();
         var tangents = new List<Vector4>();
         for (int x = 0; x < 16; x++)
         {
             for (int z = 0; z < 16; z++)
             {
                 Vector3 position = new Vector3(x, 0, z);
 
                 vertices.Add(position);
                 uvs.Add(new Vector2((float) x / 16, (float) z / 16);
                 tangents.Add(new Vector4(1, 0, 1, -1));
             }
         }
 
         var triangles = new List<int>();
         for (int x = 0, vrt = 0; x < 15; x++)
         {
             for (int z = 0; z < 15; z++, vrt++)
             {
                 triangles.Add(vrt);
                 triangles.Add(vrt + 16);
                 triangles.Add(vrt + 1);
 
                 triangles.Add(vrt + 16);
                 triangles.Add(vrt + 17);
                 triangles.Add(vrt + 1);
             }
         }
 
         var mesh = new Mesh();
         mesh.name = "Terrain";
         mesh.vertices = vertices.ToArray();
         mesh.triangles = triangles.ToArray();
         mesh.uv = uvs.ToArray();
         mesh.tangents = tangents.ToArray();
         mesh.RecalculateNormals();
 
         _meshFilter.sharedMesh = mesh;
     }

alt text

Answer 1

It was vrt++ fault. Calculate it as y*numVerticesX + x; instead.

 public void GenerateMesh ( int numVerticesX = 16 , int numVerticesZ = 16 )
 {
     var vertices = new List<Vector3>();
     var normals = new List<Vector3>();
     var uvs = new List<Vector2>();
     for( int y=0 ; y<numVerticesZ ; y++ )
     for( int x=0 ; x<numVerticesX ; x++ )
     {
         float tx = (float)x / (float)(numVerticesX-1);
         float ty = (float)y / (float)(numVerticesZ-1);
         vertices.Add( new Vector3(-0.5f+tx,0,-0.5f+ty) );
         normals.Add( Vector3.up );
         uvs.Add( new Vector2(tx,ty) );
     }
 
     var indices = new List<int>();
     for( int y=0 ; y<(numVerticesZ-1) ; y++ )
     for( int x=0 ; x<(numVerticesX-1) ; x++ )
     {
         int quad = y*numVerticesX + x;
 
         indices.Add(quad);
         indices.Add(quad+numVerticesX);
         indices.Add(quad+numVerticesX+1);
 
         indices.Add(quad);
         indices.Add(quad+numVerticesX+1);
         indices.Add(quad+1);
     }
 
     var mesh = new Mesh();
     mesh.name = $"Terrain {mesh.GetHashCode()}";
     mesh.vertices = vertices.ToArray();
     mesh.triangles = indices.ToArray();
     mesh.uv = uvs.ToArray();
     mesh.normals = normals.ToArray();
 
     _meshFilter.sharedMesh = mesh;
 }

How to generate a subdivided plane mesh

1 Reply

Your answer

Follow this Question

Related Questions