creating mesh from list of vector 3's

Hi all, so I've got 2 lists of vector 3's, one for the left hand side of the mesh and one for the right, when I run it all I end up creating is a mesh with the last 2 points of each list.
Any help appreciated.

Code (CSharp):

1. for (int i = 0; i < leftPos.Count; i++) {
2.  
3.             if (i > 0) {
4.  
5.                 current_CL_LEFT = leftPos [i];
6.                 current_CL_RIGHT = rightPos [i];
7.                 previous_CL_LEFT = leftPos [i - 1];
8.                 previous_CL_RIGHT = rightPos [i - 1];
9.  
10.                 Vector3[] vertices = {
11.  
12.                     previous_CL_RIGHT,    // 0
13.                     previous_CL_LEFT,    // 1
14.                     current_CL_LEFT,     // 2
15.                     current_CL_RIGHT,    // 3                            
16.                
17.                 };
18.  
19.                 int[] triangles = {
20.                     0, 1, 2,
21.                     2, 3, 0
22.  
23.                 };
24.  
25.                 Vector2 []uv = {
26.                     new Vector2 (0, 0),
27.                     new Vector2 (1, 0),
28.                     new Vector2 (1, 1),
29.                     new Vector2 (0, 1),
30.                 };
31.  
32.                 Vector3[] norms = {
33.  
34.                     Vector3.up,
35.                     Vector3.up,
36.                     Vector3.up,
37.                     Vector3.up
38.                 };
39.  
40.                 Mesh mesh = new Mesh ();
41.                 mesh.vertices = vertices;
42.                 mesh.triangles = triangles;
43.                 mesh.uv = uv;
44.                 mesh.normals = norms;
45.  
46.  
47.                 mesh_filter.mesh = mesh;
48.  
49.  
50.             }
51.        
52.                
53.        
54.         }    //

 

Every time you do

Code (CSharp):

1. mesh.vertices = vertices;
2.                 mesh.triangles = triangles;
3.                 mesh.uv = uv;
4.                 mesh.normals = norms;

you override values you putted there on previous iteration. Only last vertices triangles, uvs and normals remains. You need to add, not override.

 

Hi thanks for the reply, sorry if a basic question but how do I add instead of override ?

 

Hi thanks but i now get the following error from this line : mesh.vertices += vertices;
error CS0019: Operator `+=' cannot be applied to operands of type `UnityEngine.Vector3[]' and `UnityEngine.Vector3[]'

 

He's misguided you. Operator += is not intended for arrays, that's why you get that error. You need to

Code (CSharp):

1.  
2. List<Vector3> vertices = new List<Vector3>();
3. Mesh mesh = meshFilter.mesh;
4.  
5. mesh.Clear();
6.  
7. for(...) {
8.    vertices.AddRange(<your list of vertices for 1 element>);
9. }
10.  
11. mesh.vertices = vertices.ToArray();
12.  

 

Try this one:

Code (CSharp):

1. List<Vector3> Vertices = new List<Vector3>();
2.         List<int> Triangles = new List<int>();
3.         List<Vector2> UV = new List<Vector2>();
4.         List<Vector3> Normals = new List<Vector3>();
5.  
6.  
7.         for (int i = 1; i < leftPos.Count; i++)
8.         {
9.  
10.                 current_CL_LEFT = leftPos[i];
11.                 current_CL_RIGHT = rightPos[i];
12.                 previous_CL_LEFT = leftPos[i - 1];
13.                 previous_CL_RIGHT = rightPos[i - 1];
14.  
15.                 Vector3[] vertices = {
16.  
17.                     previous_CL_RIGHT,    // 0
18.                     previous_CL_LEFT,    // 1
19.                     current_CL_LEFT,     // 2
20.                     current_CL_RIGHT,    // 3                        
21.            
22.                 };
23.  
24.                 int j = (i - 1)* 4;
25.  
26.                 int[] triangles = {
27.                     0+j, 1+j, 2+j,
28.                     2+j, 3+j, 0+j
29.  
30.                 };
31.  
32.                 Vector2[] uv = {
33.                     new Vector2 (0, 0),
34.                     new Vector2 (1, 0),
35.                     new Vector2 (1, 1),
36.                     new Vector2 (0, 1),
37.                 };
38.  
39.                 Vector3[] norms = {
40.  
41.                     Vector3.up,
42.                     Vector3.up,
43.                     Vector3.up,
44.                     Vector3.up
45.                 };
46.  
47.                 Vertices.AddRange(vertices);
48.                 Triangles.AddRange(triangles);
49.                 UV.AddRange(uv);
50.                 Normals.AddRange(norms);
51.         }
52.         Mesh mesh = new Mesh();
53.         mesh.vertices = Vertices.ToArray();
54.         mesh.triangles = Triangles.ToArray();
55.         mesh.uv = UV.ToArray();
56.         mesh.normals = Normals.ToArray();
57.         mesh_filter.mesh = mesh;

 

Thanks guys, will try tomorrow now

 

There are some helper classes in Unity that you might find useful for winding your own geometry, such as the UnityEngine.UI.VertexHelper class. Procedural Geometry in Unity is a amazingly easy compared to most other general purpose APIs.

If you want to see some more handy examples of procedural generation, check out my little "makegeo" project, which is just an ad-hoc collection of random procgen routines.

MakeGeo is presently hosted at these locations:

https://bitbucket.org/kurtdekker/makegeo

https://github.com/kurtdekker/makegeo

https://gitlab.com/kurtdekker/makegeo