sphere.py 文件源码

def __get_initial_candidates(self):
        if self.__max_cells >= 4:
            cap = self.__region.get_cap_bound()
            level = min(CellId.min_width().get_max_level(
                        2 * cap.angle().radians),
                        min(self.__max_level, CellId.MAX_LEVEL - 1))

            if self.__level_mod > 1 and level > self.__min_level:
                level -= (level - self.__min_level) % self.__level_mod

            if level > 0:
                cell_id = CellId.from_point(cap.axis())
                vertex_neighbors = cell_id.get_vertex_neighbors(level)
                for neighbor in vertex_neighbors:
                    self.__add_candidate(self.__new_candidate(Cell(neighbor)))
                return

        for face in range(6):
            self.__add_candidate(self.__new_candidate(FACE_CELLS[face]))