io_import_scene_lwo.py

        surf_data.bl_mat.raytrace_transparency.ior= surf_data.rind
        surf_data.bl_mat.raytrace_transparency.gloss_factor= 1.0 - surf_data.tblr
        surf_data.bl_mat.translucency= surf_data.trnl
        surf_data.bl_mat.specular_hardness= int(4*((10*surf_data.glos)*(10*surf_data.glos)))+4
        # The Gloss is as close as possible given the differences.

    # Single layer objects use the object file's name instead.
    if len(object_layers) and object_layers[-1].name == 'Layer 1':
        object_layers[-1].name= object_name
        print("Building '%s' Object" % object_name)
    else:
        print("Building %d Objects" % len(object_layers))

    # Before adding any meshes or armatures go into Object mode.
    if bpy.ops.object.mode_set.poll():
        bpy.ops.object.mode_set(mode='OBJECT')

    for layer_data in object_layers:
        me= bpy.data.meshes.new(layer_data.name)
        me.vertices.add(len(layer_data.pnts))
        me.tessfaces.add(len(layer_data.pols))
        # for vi in range(len(layer_data.pnts)):
        #     me.vertices[vi].co= layer_data.pnts[vi]

        # faster, would be faster again to use an array
        me.vertices.foreach_set("co", [axis for co in layer_data.pnts for axis in co])

        ngons= {}   # To keep the FaceIdx consistent, handle NGons later.
        edges= []   # Holds the FaceIdx of the 2-point polys.
        for fi, fpol in enumerate(layer_data.pols):
            fpol.reverse()   # Reversing gives correct normal directions
            # PointID 0 in the last element causes Blender to think it's un-used.
            if fpol[-1] == 0:
                fpol.insert(0, fpol[-1])
                del fpol[-1]

            vlen= len(fpol)
            if vlen == 3 or vlen == 4:
                for i in range(vlen):
                    me.tessfaces[fi].vertices_raw[i]= fpol[i]
            elif vlen == 2:
                edges.append(fi)
            elif vlen != 1:
                ngons[fi]= fpol  # Deal with them later

        ob= bpy.data.objects.new(layer_data.name, me)
        bpy.context.scene.objects.link(ob)
        ob_dict[layer_data.index]= [ob, layer_data.parent_index]

        # Move the object so the pivot is in the right place.
        ob.location= layer_data.pivot

        # Create the Material Slots and assign the MatIndex to the correct faces.
        mat_slot= 0
        for surf_key in layer_data.surf_tags:
            if object_tags[surf_key] in object_surfs:
                me.materials.append(object_surfs[object_tags[surf_key]].bl_mat)

                for fi in layer_data.surf_tags[surf_key]:
                    me.tessfaces[fi].material_index= mat_slot
                    me.tessfaces[fi].use_smooth= object_surfs[object_tags[surf_key]].smooth

                mat_slot+=1

        # Create the Vertex Groups (LW's Weight Maps).
        if len(layer_data.wmaps) > 0:
            print("Adding %d Vertex Groups" % len(layer_data.wmaps))
            for wmap_key in layer_data.wmaps:
                vgroup= ob.vertex_groups.new()
                vgroup.name= wmap_key
                wlist= layer_data.wmaps[wmap_key]
                for pvp in wlist:
                    vgroup.add((pvp[0], ), pvp[1], 'REPLACE')

        # Create the Shape Keys (LW's Endomorphs).
        if len(layer_data.morphs) > 0:
            print("Adding %d Shapes Keys" % len(layer_data.morphs))
            ob.shape_key_add('Basis')   # Got to have a Base Shape.
            for morph_key in layer_data.morphs:
                skey= ob.shape_key_add(morph_key)
                dlist= layer_data.morphs[morph_key]
                for pdp in dlist:
                    me.shape_keys.key_blocks[skey.name].data[pdp[0]].co= [pdp[1], pdp[2], pdp[3]]

        # Create the Vertex Color maps.
        if len(layer_data.colmaps) > 0:
            print("Adding %d Vertex Color Maps" % len(layer_data.colmaps))
            for cmap_key in layer_data.colmaps:
                map_pack= create_mappack(layer_data, cmap_key, "COLOR")
                me.vertex_colors.new(cmap_key)
                vcol= me.tessface_vertex_colors[-1]
                if not vcol or not vcol.data:
                    break
                for fi in map_pack:
                    if fi > len(vcol.data):
                        continue
                    face= map_pack[fi]
                    colf= vcol.data[fi]

                    if len(face) > 2:
                        colf.color1= face[0]
                        colf.color2= face[1]
                        colf.color3= face[2]
                    if len(face) == 4:
                        colf.color4= face[3]

        # Create the UV Maps.
        if len(layer_data.uvmaps) > 0:
            print("Adding %d UV Textures" % len(layer_data.uvmaps))
            for uvmap_key in layer_data.uvmaps:
                map_pack= create_mappack(layer_data, uvmap_key, "UV")
                me.uv_textures.new(name=uvmap_key)
                uvm= me.tessface_uv_textures[-1]
                if not uvm or not uvm.data:
                    break
                for fi in map_pack:
                    if fi > len(uvm.data):
                        continue
                    face= map_pack[fi]
                    uvf= uvm.data[fi]

                    if len(face) > 2:
                        uvf.uv1= face[0]
                        uvf.uv2= face[1]
                        uvf.uv3= face[2]
                    if len(face) == 4:
                        uvf.uv4= face[3]

        # Now add the NGons.
        if len(ngons) > 0:
            for ng_key in ngons:
                face_offset= len(me.tessfaces)
                ng= ngons[ng_key]
                v_locs= []
                for vi in range(len(ng)):
                    v_locs.append(mathutils.Vector(layer_data.pnts[ngons[ng_key][vi]]))
                tris= tessellate_polygon([v_locs])
                me.tessfaces.add(len(tris))
                for tri in tris:
                    face= me.tessfaces[face_offset]
                    face.vertices_raw[0]= ng[tri[0]]
                    face.vertices_raw[1]= ng[tri[1]]
                    face.vertices_raw[2]= ng[tri[2]]
                    face.material_index= me.tessfaces[ng_key].material_index
                    face.use_smooth= me.tessfaces[ng_key].use_smooth
                    face_offset+= 1

        # FaceIDs are no longer a concern, so now update the mesh.
        has_edges= len(edges) > 0 or len(layer_data.edge_weights) > 0
        me.update(calc_edges=has_edges)

        # Add the edges.
        edge_offset= len(me.edges)
        me.edges.add(len(edges))
        for edge_fi in edges:
            me.edges[edge_offset].vertices[0]= layer_data.pols[edge_fi][0]
            me.edges[edge_offset].vertices[1]= layer_data.pols[edge_fi][1]
            edge_offset+= 1

        # Apply the Edge Weighting.
        if len(layer_data.edge_weights) > 0:
            for edge in me.edges:
                edge_sa= "{0} {1}".format(edge.vertices[0], edge.vertices[1])
                edge_sb= "{0} {1}".format(edge.vertices[1], edge.vertices[0])
                if edge_sa in layer_data.edge_weights:
                    edge.crease= layer_data.edge_weights[edge_sa]
                elif edge_sb in layer_data.edge_weights:
                    edge.crease= layer_data.edge_weights[edge_sb]

        # Unfortunately we can't exlude certain faces from the subdivision.
        if layer_data.has_subds and add_subd_mod:
            ob.modifiers.new(name="Subsurf", type='SUBSURF')

        # Should we build an armature from the embedded rig?
        if len(layer_data.bones) > 0 and skel_to_arm:
            bpy.ops.object.armature_add()
            arm_object= bpy.context.active_object
            arm_object.name= "ARM_" + layer_data.name
            arm_object.data.name= arm_object.name
            arm_object.location= layer_data.pivot
            bpy.ops.object.mode_set(mode='EDIT')
            build_armature(layer_data, arm_object.data.edit_bones)
            bpy.ops.object.mode_set(mode='OBJECT')

        # Clear out the dictionaries for this layer.
        layer_data.bone_names.clear()
        layer_data.bone_rolls.clear()
        layer_data.wmaps.clear()
        layer_data.colmaps.clear()
        layer_data.uvmaps.clear()
        layer_data.morphs.clear()
        layer_data.surf_tags.clear()

        # We may have some invalid mesh data, See: [#27916]
        # keep this last!
        print("validating mesh: %r..." % me.name)
        me.validate(verbose=1)
        print("done!")

    # With the objects made, setup the parents and re-adjust the locations.
    for ob_key in ob_dict:
        if ob_dict[ob_key][1] != -1 and ob_dict[ob_key][1] in ob_dict:
            parent_ob = ob_dict[ob_dict[ob_key][1]]
            ob_dict[ob_key][0].parent= parent_ob[0]
            ob_dict[ob_key][0].location-= parent_ob[0].location

    bpy.context.scene.update()

    print("Done Importing LWO File")


from bpy.props import StringProperty, BoolProperty


class IMPORT_OT_lwo(bpy.types.Operator):
    """Import LWO Operator"""
    bl_idname= "import_scene.lwo"
    bl_label= "Import LWO"
    bl_description= "Import a LightWave Object file"
    bl_options= {'REGISTER', 'UNDO'}

    filepath= StringProperty(name="File Path", description="Filepath used for importing the LWO file", maxlen=1024, default="")

    ADD_SUBD_MOD= BoolProperty(name="Apply SubD Modifier", description="Apply the Subdivision Surface modifier to layers with Subpatches", default=True)
    LOAD_HIDDEN= BoolProperty(name="Load Hidden Layers", description="Load object layers that have been marked as hidden", default=False)
    SKEL_TO_ARM= BoolProperty(name="Create Armature", description="Create an armature from an embedded Skelegon rig", default=True)

    def execute(self, context):
        load_lwo(self.filepath,
                 context,
                 self.ADD_SUBD_MOD,
                 self.LOAD_HIDDEN,
                 self.SKEL_TO_ARM)
        return {'FINISHED'}

    def invoke(self, context, event):
        wm= context.window_manager
        wm.fileselect_add(self)
        return {'RUNNING_MODAL'}


def menu_func(self, context):
    self.layout.operator(IMPORT_OT_lwo.bl_idname, text="LightWave Object (.lwo)")


def register():
    bpy.utils.register_module(__name__)

    bpy.types.INFO_MT_file_import.append(menu_func)


def unregister():
    bpy.utils.unregister_module(__name__)

    bpy.types.INFO_MT_file_import.remove(menu_func)

if __name__ == "__main__":
    register()