三角形插值
https://codeplea.com/triangular-interpolation
https://www.cnblogs.com/graphics/archive/2010/08/09/1795348.html
https://www.cnblogs.com/YouXiangLiThon/p/7997796.html 叉乘
https://codeplea.com/triangular-interpolation
https://www.cnblogs.com/graphics/archive/2010/08/09/1795348.html
https://www.cnblogs.com/YouXiangLiThon/p/7997796.html 叉乘