Procedurally Generated mesh not rendering all triangles,Procedurally generated mesh isn't rendering all triangles?

Question

I'm working on making a planet generator, and to start it off I'm trying to see if I can make a plane of procedurally generates squares. I have it print out each time a vertex is made, and every time a square is made out of 2 triangles, as well as the coordinates, and even though the console prints out everything properly, only the top row of squares appear.

If it helps, this is my spaghetti-looking code: (resolution is the amount of squares each side, so a res of 2 would make a 2 by 2 plane, 3 would make a 3 by 3 plane, etc)

 int resolution=10;
         int numVert = (resolution+1)*(resolution+1)+1;
         int numTri = resolution*resolution*6;
 
         Debug.Log(numVert);
         Debug.Log(numTri);
         Mesh mesh = new Mesh();
         Debug.Log(resolution);
         Vector3[] vertices = new Vector3[numVert];
         int[] triangles = new int[numTri];
 
         int i = 0;
         int i2 = 0;
         int x = 0;
         int y = 0;
         for (y = 0; y <= resolution; y++)
         {
             for (x = 0; x <= resolution; x++)
             {
                 vertices[i+1] = new Vector3(x*2,-y*2,0);
                 i=i+1;
                 Debug.Log("Vertex made at "+x+","+y);
             }
         }
         for (y = 1; y <= resolution; y++)
         {
             for (x = 1; x <= resolution; x++)
             {
                 triangles[i2] = x+resolution+1;
                 triangles[i2+1] = x;
                 triangles[i2+2] = x+1;
                 triangles[i2+3] = x+resolution+1;
                 triangles[i2+4] = x+1;
                 triangles[i2+5] = x+resolution+2;
                 i2=i2+6;
                 Debug.Log("Square made at "+x+","+y);
             }
         }
         mesh.vertices = vertices;
         mesh.triangles = triangles;
         GetComponent<MeshFilter>().mesh = mesh;
         MeshCollider meshc = gameObject.AddComponent(typeof(MeshCollider)) as MeshCollider;
         meshc.sharedMesh = mesh;
     }

Answer 1

Ok, Mr. you start from a 0 indexing vertex list, u grow up of maxX (resolution) for each y, that for the entire first row is 0.

          for (y = 1; y <= resolution; y++)
          {
              for (x = 1; x <= resolution; x++)
 {
 ....

you start here for 1 while doing calculation. resulting in index 0 never being mentioned, and thats what i would do (i did). you take count of the whole square while triangulating. so u need to check only for the square in a

resolution-1 * resolution-1 grid

those are the number of square in a grid of resolution*resolution vertices so u do

          for (y = 0; y <= resolution-1; y++)
          {
              for (x = 0; x <= resolution-1; x++)
              {

and then when selecting the corresponding vertex index u start from the point 0, 0 of the grid and count from there

 x---------x+1
 |          |
 x+X------x+X+1

entering the indexing like this

                      triangles[i2] = x;
                      triangles[i2+1] = x+1;
                      triangles[i2+2] = x+resolution;
                      triangles[i2+3] = x+resolution;
                      triangles[i2+4] = x+1;
                      triangles[i2+5] = x+resolution+1;
                      i2=i2+6;

im actually not sure by the orther, but u can figure it out i hope. Good Luck!

edit: i re-read the answer that i posted and pointed out that x, must be accessed linearly so, u can add another counter, like int index, and then when the last x occur u can call index++

 triangles[i2] = index;
 triangles[i2+1] = index+1;
 triangles[i2+2] = index+resolution;
 triangles[i2+3] = index+resolution;
 triangles[i2+4] = index+1;
 triangles[i2+5] = (index++)+resolution+1
 i2=i2+6;
 
 u can rewrite the whole thing as a single for loop int i = 0; i<((resolution-1)*(resolution-1));i++

the y would be i divided / by resolution

removing i2 at all stepping i for 6 like this

     for(int i = 0 ;i<((resolution-1)*(resolution-1));i++){
 int triangle_index = i*6;
     int y = i / resolution;
     //triangle[triangle_index+0] = i;//i+1,i+resolution
     //blabla...
     
     //i2 no more
     }

Procedurally Generated mesh not rendering all triangles,Procedurally generated mesh isn't rendering all triangles?

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