how to subdivide a mesh in unity in code

so i have a box built in unity by code

    	VectorPosition = new List<Vector3>();
	VectorPosition.Add(new Vector3(pos.x+Size, pos.y-Size, pos.z-Size) * 0.5f);
   VectorPosition.Add(new Vector3(pos.x+Size, pos.y+Size, pos.z-Size)* 0.5f); 
   VectorPosition.Add(new Vector3(pos.x-Size, pos.y-Size, pos.z-Size)* 0.5f);
   VectorPosition.Add(new Vector3(pos.x-Size, pos.y+Size, pos.z-Size)* 0.5f);  

	VectorPosition.Add(new Vector3(pos.x+Size, pos.y-Size, pos.z+Size) * 0.5f);
   VectorPosition.Add(new Vector3(pos.x+Size, pos.y+Size, pos.z+Size)* 0.5f); 
   VectorPosition.Add(new Vector3(pos.x-Size, pos.y-Size, pos.z+Size)* 0.5f);
   VectorPosition.Add(new Vector3(pos.x-Size, pos.y+Size, pos.z+Size)* 0.5f); 
	verts = new Vector3[VectorPosition.Count];
	for(int i = 0; i < verts.Length; i++) {
		verts _= VectorPosition*;*_

* }*

* tris = new int[36] {0, 1, 5, 5, 4, 0,*
0, 4, 6, 6, 2, 0,
4, 5, 7, 7, 6, 4,
3, 7, 5, 5, 1, 3,
6, 7, 3, 3, 2, 6,
0, 2, 3, 3, 1, 0};
but how would i go about getting the “tris” set up right when i subdivide because obviously i cant do that for say the 10th subdivision i assume there is some algorithm of some sort
any ideas or links?

Best might be to look at non-Unity sources. Subdividing is subdividing.

A real Modeling program (and you can look how Blender code does it, but tons of work) maintains a list of quad faces, another of edges … . Subdivide is a pile of loops and lists: work through all of quads, breaking each edge in two and replacing the quad with 4 new quads. Interpolate the UVs. Then go through all the broken edges that have adjacent tris, and fix those by breaking the tri with one extra edge (but for just a cube, you won’t have any.) The final result would be copied into the Unity Mesh class.

A tri-subdivide (where you just make a new center-point for each tri and break 1 tri into 3) would be simpler. Could probably do that directly from the Unity Mesh class Tri list. But probably not what you want.