Change uvs on texture packing

Hi. I'm doing some optimization stuff and trying to pack all materials to one material. Here's my problem: I have mesh with 5 submeshes(5 materials with different textures). I can pack all textures to one atlas and use just that texture. Problem is I don't know how to recalculate new uvs to my new atlas. Here's the code:

 private void CreateMeshTexture ()
     {        
         //get all textures
         var rend = renderer;
         var atlasMaterial = new Material (Shader.Find ("Mobile/Diffuse")); 
         var meshFilter = GetComponent<MeshFilter> ();
         var textures = new List<Texture2D> ();
     
         foreach (var mat in rend.materials) {
             textures.Add ((Texture2D)mat.mainTexture);
         }
  
         
         //create texture atlas
         textureAtlas = new Texture2D (maxSquareTextureSize, maxSquareTextureSize); 
         Rect[] coords = textureAtlas.PackTextures (textures.ToArray (), 0, maxSquareTextureSize);  
         atlasMaterial.mainTexture = textureAtlas; 
         
         //update materials
         rend.material = atlasMaterial;
         for (int i = 0; i < rend.materials.Length; ++i) {
             rend.materials[i] = atlasMaterial;
         }
         
         //correct uvs
         Vector2[] oldUV, newUV;
         oldUV = meshFilter.mesh.uv; 
         newUV = new Vector2[oldUV.Length];
         
         //how to set new uvs?
         
     }

Does anybody know how to recalculate uvs? Is that possible?