open surface的用法和样例：
例句
- Reflection from a rough surface is often called diffuse reflection.
粗糙表面的反射常常叫做漫射。 - It is fairly common these days for modeling applications to render a rough surface for selected objects, while leaving unselected objects as wire frames.
所有对象都需要用边框代表，建模应用程序通常只绘制所选对象的粗糙表面，而用线框代表未选对象。
