UnityEngine.StaticBatchingUtility.InternalCombineIndices C# (CSharp) Method

        internal static extern void InternalCombineIndices(MeshSubsetCombineUtility.SubMeshInstance[] submeshes, [Writable] Mesh combinedMesh);
        [MethodImpl(MethodImplOptions.InternalCall)]

 private static void MakeBatch(List <MeshSubsetCombineUtility.MeshInstance> meshes, List <MeshSubsetCombineUtility.SubMeshInstance> subsets, List <GameObject> subsetGOs, Transform staticBatchRootTransform, int batchIndex)
 {
     if (meshes.Count >= 2)
     {
         MeshSubsetCombineUtility.MeshInstance[]    instanceArray = meshes.ToArray();
         MeshSubsetCombineUtility.SubMeshInstance[] submeshes     = subsets.ToArray();
         string meshName = "Combined Mesh";
         meshName = meshName + " (root: " + ((staticBatchRootTransform == null) ? "scene" : staticBatchRootTransform.name) + ")";
         if (batchIndex > 0)
         {
             meshName = meshName + " " + (batchIndex + 1);
         }
         Mesh combinedMesh = StaticBatchingUtility.InternalCombineVertices(instanceArray, meshName);
         StaticBatchingUtility.InternalCombineIndices(submeshes, combinedMesh);
         int subSetIndexForMaterial = 0;
         for (int i = 0; i < submeshes.Length; i++)
         {
             subSetIndexForMaterial++;
         }
     }
 }