>官网Reference,Draw Triangle Back Faces in Red
>If a self-intersecting shell is drawn, then inside surfaces may be exposed. Even if the shell is watertight, a few stray pixels from an inside surface may "show through", depending on how the graphics card renders triangles. This setting determines whether those surfaces are discarded, or drawn highlighted in red.
大概就是自相交的面会渲染成红色。这一般来讲是软件渲染问题,可以用行为栏里的 分析-显示干涉零件/显示孤立边 来检查是否与渲染有关。