UV Mesh modification via script to support texture atlas concept with hexagonal tiles

Unity Community,
This is my first post to the forums as I am a believer in figuring stuff out through research before asking questions. I am unable to find a clear example which will help me adjust the UV mesh coordinates of a hexagon to support a texture atlas. I have scoured the forums, read up on the Mesh-UV API but still don't have a clear picture of how to generate a script which will adjust the UV of the mesh to swap between the two textures in the atlas (goal is to have many textures in atlas once I complete this proof of concept). Utilizing an offset won't work as this doesn't reduce the draw calls.

The hexagon maps to 128x128 pixel texture and I currently have two in the atlas for testing (256x128).




The mesh was generated in Blender and not procedurally generated.
Any help is thoroughly appreciated. I included some of my troubleshooting code as I think this is on the correct path.

Code (CSharp):

1.  
2. Mesh mesh = LastHitObject.GetComponent<MeshFilter>().mesh;
3. Vector3[] vertices = mesh.vertices;
4. Vector2[] uvs = new Vector2[vertices.Length];
5.  
6. for (int i=0; i < uvs.Length; i++) {
7.     //Some modification to the 'x' component based on the number of textures?  Possibly 0.5?
8.     uvs[i] = new Vector2(vertices[i].x, vertices[i].z);
9. }
10. mesh.uv = uvs;
11. LastHitObject.GetComponent<MeshFilter>().mesh.uv = mesh.uv;

-Romexus

 

This problem continued to haunt me until I found a creative way to handle the issue. Instead of finding a way to adjust the UV associated, I created a similar effect by using a floating hexagonal tile with a different material. I placed this 'selected hexagon' a few units above the hexagonal grid by matching the transforms through ray casting. From the top down perspective it looks like the material has adjusted when the mouse scrolls over a playable grid.



The green hexagon above is the hover effect in the game.