utils.py

            armMod.use_bone_envelopes = False
            armMod.use_vertex_groups = True
            treeObj.parent = bpy.data.objects['treeArm']

        # add skin modifier and set data
        skinMod = treeObj.modifiers.new('Skin', 'SKIN')
        skinMod.use_smooth_shade = True
        if previewArm:
            skinMod.show_viewport = False
        skindata = treeObj.data.skin_vertices[0].data
        for i, radius in enumerate(vert_radius):
            skindata[i].radius = radius
            skindata[i].use_root = root_vert[i]

        print("mesh time", time.time() - t1)