Procedural Box: Only the first face is displayed

Questions & Answers
1

Hi,

I’m trying to generate a box procedurally. Everything is almost working, except I have only one face showing up, and it’s always the first face to be processed. Here is my code:

    using UnityEngine;
    using System.Collections;
    using System.Collections.Generic;

    public class BlockPart : MonoBehaviour
    {
        MeshFilter filter;
        Renderer myRenderer;
        public Vector3 dimensions;
        public Texture2D tex;
        public List<Vector3> vertices;
        public List<int> triangles;
        public List<Vector3> normals;
        public List<Vector2> uv;
        List<Vector3> tmpVert = new List<Vector3>();
        List<int> tmpTris = new List<int>();
        List<Vector3> tmpNorm = new List<Vector3>();
        List<Vector2> tmpUvs = new List<Vector2>();
        public float myAngle = 0;

        void Awake()
        {
            dimensions = new Vector3(1, 2.2f, 1);
            filter = GetComponent<MeshFilter>();
            myRenderer = GetComponent<Renderer>();
        }

        public void reinit()
        {
            filter.mesh = new Mesh();
            vertices = new List<Vector3>();
            triangles = new List<int>();
            normals = new List<Vector3>();
            uv = new List<Vector2>();
        }

        public void addPane(Vector3 norm, Vector3 first, Vector3 second, Vector3 third, Vector3 forth)
        {
            tmpVert = new List<Vector3>() { new Vector3(), new Vector3(), new Vector3(), new Vector3() };
            tmpTris = new List<int>() { 0, 0, 0, 0, 0, 0 };
            tmpNorm = new List<Vector3>() { new Vector3(), new Vector3(), new Vector3(), new Vector3() };
            tmpUvs = new List<Vector2>() { new Vector2(), new Vector2(), new Vector2(), new Vector2() };
            tmpVert[0] = first;
            tmpVert[1] = second;
            tmpVert[2] = third;
            tmpVert[3] = forth;

            tmpTris[0] = 0;
            tmpTris[1] = 1;
            tmpTris[2] = 2;

            tmpTris[3] = 0;
            tmpTris[4] = 2;
            tmpTris[5] = 3;
            
            tmpNorm[0] = norm;
            tmpNorm[1] = norm;
            tmpNorm[2] = norm;
            tmpNorm[3] = norm;
            tmpUvs[0] = new Vector2(0, 0);
            tmpUvs[1] = new Vector2(0, 1);
            tmpUvs[2] = new Vector2(1, 1);
            tmpUvs[3] = new Vector2(1, 0);
            vertices.AddRange(tmpVert);
            triangles.AddRange(tmpTris);
            normals.AddRange(tmpNorm);
            uv.AddRange(tmpUvs);
        
        }

        public Vector3 newV(float x, float y, float z)
        {
            return new Vector3(x, y, z);
        }

        public void addBox()
        {

        }

        public Vector3 RotatePointAroundPivot(Vector3 point, float angle)
        {
            return Quaternion.AngleAxis(angle, Vector3.up) * point;

        }

        void createMesh()
        {
            filter.mesh.vertices = vertices.ToArray();
            filter.mesh.normals = normals.ToArray();
            filter.mesh.uv = uv.ToArray();
            filter.mesh.triangles = triangles.ToArray();
            myRenderer.material.mainTexture = tex;
            filter.mesh.RecalculateBounds();
            filter.mesh.RecalculateNormals();
            filter.mesh.Optimize();
        }
	
	    void Update ()
	    {
            // Here, no matter what I do the first call on "addPane" will be the only one to be drawn
            myAngle += Time.deltaTime * 5f;
            reinit();
            addPane(-Vector3.forward, 

                    newV(-0.05f, 0, -0.05f),
                    newV(-0.05f, 2.2f, -0.05f),
                    newV(0.05f, 2.2f, -0.05f),
                    newV(0.05f, 0, -0.05f));
            addPane(Vector3.forward,
                    newV(0.05f, 0, 0.05f),
                    newV(0.05f, 2.2f, 0.05f),
                    newV(-0.05f, 2.2f, 0.05f),
                    newV(-0.05f, 0, 0.05f));
            addPane(-Vector3.left,
                    newV(-0.05f, 0, 0.05f),
                    newV(-0.05f, 2.2f, 0.05f),
                    newV(-0.05f, 2.2f, -0.05f),
                    newV(-0.05f, 0, -0.05f));
            addPane(Vector3.right,
                    newV(0.05f, 0, -0.05f),
                    newV(0.05f, 2.2f, -0.05f),
                    newV(0.05f, 2.2f, 0.05f),
                    newV(0.05f, 0, 0.05f));
            createMesh();
	    }
    }

I’ve tried several approaches and I am running out of ideas.

edit: Separately, the faces are correct. They are all clockwise, display correctly with the proper UV, normals and triangles.

Thanks for your help.

2

At least you never add numbers beyond 0-3 to your triangles array, so those are the only 4 vertices you use to draw geometry

...
tmpTris[0] = 0;
tmpTris[1] = 1;
tmpTris[2] = 2;
 
tmpTris[3] = 0;
tmpTris[4] = 2;
tmpTris[5] = 3;
...

For every face you draw, you have to add 4 to the index from which you start the next time.