This is a Unity Editor tool about Flip Normals in Hierarchy.
你只需要将以下.cs文件放置在名称为 Editor 的文件夹下即可，然后即可在 Hierarchy 视图对象的快捷菜单中增加 Flip Mesh Normals（反转网格法线）项。
You just need to place the following .cs files under the folder named Editor, and then you can add the Flip Mesh Normals item in the shortcut menu of the Hierarchy view object.