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.

是C++实现的四叉树索引可以实现2D、3D图像的插入、删除、查找，源码使用使用C++11标准实现的。值得学习。-C++ implementation of the four binary tree index can achieve 2D, 3D images of the insert, delete, search, the use of source code to achieve the use of C++11. Worth learning.

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.)

用于可视化数据，包括力导向图、树图等图表的快速编程(Fast programming for visualization of data, including force oriented graphs, tree diagrams, etc)