Determination of whether a face of an object is facing backward and therefore invisible. The usual test is whether the surface normal points into the screen or not. Special attention is needed for faces on the silhouette of the object.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。