private static void ClearGrassMeshes()
        {
            Object o = Selection.activeObject;

            if (o is GTerrainGeneratedData)
            {
                GTerrainGeneratedData data = o as GTerrainGeneratedData;
                data.Internal_DeleteMeshIf((k) => { return(k.StartsWith(GCommon.GRASS_MESH_NAME_PREFIX)); });
                AssetDatabase.Refresh();
            }
        }