openGL程序 简单的程序叫你如何掌握用递归思想（L-system）画一棵树（有树干有叶子）。这也是画地形的必修课。-openGL program simple procedure called recursive thinking you how to master the (L-system) draw a tree (a tree with leaves). This is a required course terrain painting.

用L算法模拟树木生长，包含源代码，比较浅显易懂，不是很复杂。不用贴图。(Simulation of tree growth using L algorithm, including source code, relatively simple and easy to understand, not very complicated. No textures.)