https://blog.wongcw.com/2021/07/21/pedestrian-defense%e6%8a%80%e8%a1%93%e5%8f%af%e8%a2%ab%e7%94%a8%e6%96%bc%e6%aa%a2%e6%b8%ac%e9%9b%bb%e5%8b%95%e6%bb%91%e6%9d%bf%e8%bb%8a%e7%9a%84%e4%b8%8d%e7%95%b6%e4%bd%bf%e7%94%a8/