Need Help with 3D triangulation for Android

Question

I just ran into the first big problem with my current Android project. I want to display a 3d Level that is generated from 2d data. (List of obstacles with defined corner points + a fix height stored in a json file.) I managed to draw them onto the floor using some code I found online and the triangulation code from the wiki. Now to make them 3d I would have to move the top part (which I already have) up (that is eays :P) and then draw a border/walls around it.

The Problem is that all the triangulation code I found online is 2d only. In order to draw my walls/ borders I need a 3rd axis(up). But whenever I tried to modify my code to add 3d support Unity stopped rendering any triangles at all :(

Would be great If anyone could help me with this.

This is what I currently use:

  private static Mesh CreateMesh(List<Vector3> verts)
     {
         var tris = new Triangulator(verts.Select(x => x.ToVector2xz()).ToArray());
         var mesh = new Mesh();
 
         var vertices = verts.Select(x => new Vector3(x.x, x.y, x.z)).ToList();
         var indices = tris.Triangulate().ToList();
         //var uv = new List<Vector2>();
 
         var n = vertices.Count;
         for (int index = 0; index < n; index++)
         {
             var v = vertices[index];
             vertices.Add(new Vector3(v.x, v.y, v.z));
         }
 
         for (int i = 0; i < n - 1; i++)
         {
             indices.Add(i);
             indices.Add(i + n);
             indices.Add(i + n + 1);
             indices.Add(i);
             indices.Add(i + n + 1);
             indices.Add(i + 1);
         }
 
         indices.Add(n - 1);
         indices.Add(n);
         indices.Add(0);
 
         indices.Add(n - 1);
         indices.Add(n + n - 1);
         indices.Add(n);
 
 
 
         mesh.vertices = vertices.ToArray();
         mesh.triangles = indices.ToArray();
 
         mesh.RecalculateNormals();
         mesh.RecalculateBounds();
 
         return mesh;
     }

Answer 1

Figured it out on my own. Sometimes a cup of hot choclat works wonders...

       private static Mesh CreateMesh(List<Vector3> verts, float height)
         {
             var tris = new Triangulator(verts.Select(x => x.ToVector2xz()).ToArray());
             var mesh = new Mesh();
 
             var vertices = verts.Select(x => new Vector3(x.x, height, x.z)).ToList();
             var indices = tris.Triangulate().ToList();
             //var uv = new List<Vector2>();
 
             var numberOfPointsPerRing = vertices.Count;
             for (int index = 0; index < numberOfPointsPerRing; index++)
             {
                 var v = vertices[index];
                 vertices.Add(new Vector3(v.x, 0, v.z));
             }
 
             for (int i = 0; i < numberOfPointsPerRing - 1; i++)
             {
                 indices.Add(i);
                 indices.Add(i + numberOfPointsPerRing);
                 indices.Add(i + numberOfPointsPerRing + 1);
                 indices.Add(i);
                 indices.Add(i + numberOfPointsPerRing + 1);
                 indices.Add(i + 1);
             }
 
             indices.Add(numberOfPointsPerRing - 1);
             indices.Add(numberOfPointsPerRing);
             indices.Add(0);
 
             indices.Add(numberOfPointsPerRing - 1);
             indices.Add(numberOfPointsPerRing + numberOfPointsPerRing - 1);
             indices.Add(numberOfPointsPerRing);
 
 
             //Lower pointposition hinzufügen
             foreach(Vector3 point in verts)
             {
                 vertices.Add(new Vector3(point.x, 0, point.z));
             }
 
 
             int pointAbove = numberOfPointsPerRing;
             for(int i=0; i<numberOfPointsPerRing; i++)
             {
                 //right upper triangle
                 indices.Add(i);             //right down
                 indices.Add(i+1+pointAbove);//left up
                 indices.Add(i+ pointAbove); //right up
 
                 //left lower triangle
                 indices.Add(i +1);             //right down
                 indices.Add(i + 1 + pointAbove);//left up
                 indices.Add(i); //right up
 
             }
 
 
 
             mesh.vertices = vertices.ToArray();
             mesh.triangles = indices.ToArray();
 
             mesh.RecalculateNormals();
             mesh.RecalculateBounds();
 
             return mesh;
         }
 
     }
 }

Need Help with 3D triangulation for Android

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