说明：  本书是介绍基于L系统建立植物模型的专业书籍，主要是介绍了L系统的基本概念，坐标系的建立和植物拓扑结构的建立
(This book is to introduce the system based on the L model plant specialized books, mainly introduced the basic concepts of L system, coordinate the establishment and the establishment of plant topology)