openel 写的一个钟摆的程序，表现为一个长方体，做简谐运动。-openel write a pendulum of the program, expressed as a cuboid, do simple harmonic motion.

球谐函数的demo，将球谐函数可视化，加深对球谐函数的理解，对高级光照打下坚实数学基础。 我费了好大得劲，也是我在别人代码的基础上改的。-Spherical harmonics demo ball harmonic function visualization, understanding spherical harmonics, advanced lighting and lay a solid mathematical foundation. I take a great handy,