import_obj.py

    context_nurbs = {}
    nurbs = []
    context_parm = b''  # used by nurbs too but could be used elsewhere

    has_ngons = False
    # has_smoothgroups= False - is explicit with len(unique_smooth_groups) being > 0

    # Until we can use sets
    unique_materials = {}
    unique_material_images = {}
    unique_smooth_groups = {}
    # unique_obects= {} - no use for this variable since the objects are stored in the face.

    # when there are faces that end with \
    # it means they are multiline-
    # since we use xreadline we cant skip to the next line
    # so we need to know whether
    context_multi_line = b''

    print("\tparsing obj file...")
    time_sub = time.time()
#     time_sub= sys.time()

    file = open(filepath, 'rb')
    for line in file:  # .readlines():
        line = line.lstrip()  # rare cases there is white space at the start of the line

        if line.startswith(b"v "):
            line_split = line.split()
            # rotate X90: (x,-z,y)
            verts_loc.append((float_func(line_split[1]), -float_func(line_split[3]), float_func(line_split[2])))

        elif line.startswith(b"vn "):
            pass

        elif line.startswith(b"vt "):
            line_split = line.split()
            verts_tex.append((float_func(line_split[1]), float_func(line_split[2])))

        # Handel faces lines (as faces) and the second+ lines of fa multiline face here
        # use 'f' not 'f ' because some objs (very rare have 'fo ' for faces)
        elif line.startswith(b'f') or context_multi_line == b'f':

            if context_multi_line:
                # use face_vert_loc_indices and face_vert_tex_indices previously defined and used the obj_face
                line_split = line.split()

            else:
                line_split = line[2:].split()
                face_vert_loc_indices = []
                face_vert_tex_indices = []

                # Instance a face
                faces.append((\
                face_vert_loc_indices,\
                face_vert_tex_indices,\
                context_material,\
                context_smooth_group,\
                context_object\
                ))

            if strip_slash(line_split):
                context_multi_line = b'f'
            else:
                context_multi_line = b''

            for v in line_split:
                obj_vert = v.split(b'/')
                vert_loc_index = int(obj_vert[0]) - 1
                # Add the vertex to the current group
                # *warning*, this wont work for files that have groups defined around verts
                if POLYGROUPS and context_vgroup:
                    vertex_groups[context_vgroup].append(vert_loc_index)

                # Make relative negative vert indices absolute
                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                face_vert_loc_indices.append(vert_loc_index)

                if len(obj_vert) > 1 and obj_vert[1]:
                    # formatting for faces with normals and textures us
                    # loc_index/tex_index/nor_index

                    vert_tex_index = int(obj_vert[1]) - 1
                    # Make relative negative vert indices absolute
                    if vert_tex_index < 0:
                        vert_tex_index = len(verts_tex) + vert_tex_index + 1

                    face_vert_tex_indices.append(vert_tex_index)
                else:
                    # dummy
                    face_vert_tex_indices.append(0)

            if len(face_vert_loc_indices) > 4:
                has_ngons = True

        elif CREATE_EDGES and (line.startswith(b'l ') or context_multi_line == b'l'):
            # very similar to the face load function above with some parts removed

            if context_multi_line:
                # use face_vert_loc_indices and face_vert_tex_indices previously defined and used the obj_face
                line_split = line.split()

            else:
                line_split = line[2:].split()
                face_vert_loc_indices = []
                face_vert_tex_indices = []

                # Instance a face
                faces.append((\
                face_vert_loc_indices,\
                face_vert_tex_indices,\
                context_material,\
                context_smooth_group,\
                context_object\
                ))

            if strip_slash(line_split):
                context_multi_line = b'l'
            else:
                context_multi_line = b''

            isline = line.startswith(b'l')

            for v in line_split:
                vert_loc_index = int(v) - 1

                # Make relative negative vert indices absolute
                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                face_vert_loc_indices.append(vert_loc_index)

        elif line.startswith(b's'):
            if CREATE_SMOOTH_GROUPS:
                context_smooth_group = line_value(line.split())
                if context_smooth_group == b'off':
                    context_smooth_group = None
                elif context_smooth_group:  # is not None
                    unique_smooth_groups[context_smooth_group] = None

        elif line.startswith(b'o'):
            if SPLIT_OBJECTS:
                context_object = line_value(line.split())
                # unique_obects[context_object]= None

        elif line.startswith(b'g'):
            if SPLIT_GROUPS:
                context_object = line_value(line.split())
                # print 'context_object', context_object
                # unique_obects[context_object]= None
            elif POLYGROUPS:
                context_vgroup = line_value(line.split())
                if context_vgroup and context_vgroup != b'(null)':
                    vertex_groups.setdefault(context_vgroup, [])
                else:
                    context_vgroup = None  # dont assign a vgroup

        elif line.startswith(b'usemtl'):
            context_material = line_value(line.split())
            unique_materials[context_material] = None
        elif line.startswith(b'mtllib'):  # usemap or usemat
            material_libs = list(set(material_libs) | set(line.split()[1:]))  # can have multiple mtllib filenames per line, mtllib can appear more than once, so make sure only occurance of material exists

            # Nurbs support
        elif line.startswith(b'cstype '):
            context_nurbs[b'cstype'] = line_value(line.split())  # 'rat bspline' / 'bspline'
        elif line.startswith(b'curv ') or context_multi_line == b'curv':
            line_split = line.split()

            curv_idx = context_nurbs[b'curv_idx'] = context_nurbs.get(b'curv_idx', [])  # incase were multiline

            if not context_multi_line:
                context_nurbs[b'curv_range'] = float_func(line_split[1]), float_func(line_split[2])
                line_split[0:3] = []  # remove first 3 items

            if strip_slash(line_split):
                context_multi_line = b'curv'
            else:
                context_multi_line = b''

            for i in line_split:
                vert_loc_index = int(i) - 1

                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                curv_idx.append(vert_loc_index)

        elif line.startswith(b'parm') or context_multi_line == b'parm':
            line_split = line.split()

            if context_multi_line:
                context_multi_line = b''
            else:
                context_parm = line_split[1]
                line_split[0:2] = []  # remove first 2

            if strip_slash(line_split):
                context_multi_line = b'parm'
            else:
                context_multi_line = b''

            if context_parm.lower() == b'u':
                context_nurbs.setdefault(b'parm_u', []).extend([float_func(f) for f in line_split])
            elif context_parm.lower() == b'v':  # surfaces not suported yet
                context_nurbs.setdefault(b'parm_v', []).extend([float_func(f) for f in line_split])
            # else: # may want to support other parm's ?

        elif line.startswith(b'deg '):
            context_nurbs[b'deg'] = [int(i) for i in line.split()[1:]]
        elif line.startswith(b'end'):
            # Add the nurbs curve
            if context_object:
                context_nurbs[b'name'] = context_object
            nurbs.append(context_nurbs)
            context_nurbs = {}
            context_parm = b''

        ''' # How to use usemap? depricated?
        elif line.startswith(b'usema'): # usemap or usemat
            context_image= line_value(line.split())
        '''

    file.close()
    time_new = time.time()
    print("%.4f sec" % (time_new - time_sub))
    time_sub = time_new

    print('\tloading materials and images...')
    create_materials(filepath, material_libs, unique_materials, unique_material_images, IMAGE_SEARCH)

    time_new = time.time()
    print("%.4f sec" % (time_new - time_sub))
    time_sub = time_new

    if not ROTATE_X90:
        verts_loc[:] = [(v[0], v[2], -v[1]) for v in verts_loc]

    # deselect all
    bpy.ops.object.select_all(action='DESELECT')

    scene = context.scene
#     scn.objects.selected = []
    new_objects = []  # put new objects here

    print('\tbuilding geometry...\n\tverts:%i faces:%i materials: %i smoothgroups:%i ...' % (len(verts_loc), len(faces), len(unique_materials), len(unique_smooth_groups)))
    # Split the mesh by objects/materials, may
    if SPLIT_OBJECTS or SPLIT_GROUPS:
        SPLIT_OB_OR_GROUP = True
    else:
        SPLIT_OB_OR_GROUP = False

    for verts_loc_split, faces_split, unique_materials_split, dataname in split_mesh(verts_loc, faces, unique_materials, filepath, SPLIT_OB_OR_GROUP):
        # Create meshes from the data, warning 'vertex_groups' wont support splitting
        create_mesh(new_objects, has_ngons, CREATE_FGONS, CREATE_EDGES, verts_loc_split, verts_tex, faces_split, unique_materials_split, unique_material_images, unique_smooth_groups, vertex_groups, dataname)

    # nurbs support
    for context_nurbs in nurbs:
        create_nurbs(context_nurbs, verts_loc, new_objects)

    # Create new obj
    for obj in new_objects:
        base = scene.objects.link(obj)
        base.select = True

    scene.update()

    axis_min = [1000000000] * 3
    axis_max = [-1000000000] * 3

    if CLAMP_SIZE:
        # Get all object bounds
        for ob in new_objects:
            for v in ob.bound_box:
                for axis, value in enumerate(v):
                    if axis_min[axis] > value:
                        axis_min[axis] = value
                    if axis_max[axis] < value:
                        axis_max[axis] = value

        # Scale objects
        max_axis = max(axis_max[0] - axis_min[0], axis_max[1] - axis_min[1], axis_max[2] - axis_min[2])
        scale = 1.0

        while CLAMP_SIZE < max_axis * scale:
            scale = scale / 10.0

        for obj in new_objects:
            obj.scale = scale, scale, scale

    # Better rotate the vert locations
    #if not ROTATE_X90:
    #    for ob in new_objects:
    #        ob.RotX = -1.570796326794896558

    time_new = time.time()

    print("finished importing: %r in %.4f sec." % (filepath, (time_new - time_main)))
    return {'FINISHED'}


# NOTES (all line numbers refer to 2.4x import_obj.py, not this file)
# check later: line 489
# can convert now: edge flags, edges: lines 508-528
# ngon (uses python module BPyMesh): 384-414
# NEXT clamp size: get bound box with RNA
# get back to l 140 (here)
# search image in bpy.config.textureDir - load_image
# replaced BPyImage.comprehensiveImageLoad with a simplified version that only checks additional directory specified, but doesn't search dirs recursively (obj_image_load)
# bitmask won't work? - 132
# uses bpy.sys.time()

if __name__ == "__main__":
    register()