说明：  使用HTML5canvas技术制作的一个镜面反射角计算程序。使用输入框调整镜面的角度，使用鼠标调整入射角，canvas就会根据法线计算并绘制出射角
(A mirror reflection angle calculation program using HTML5canvas made. Use input box to adjust the angle of the mirror, use the mouse to adjust the angle of incidence, canvas will be calculated based on the normal map out angle)