Abstract: In many three-dimensional (3D) software, especially in 3D graphics environment system, picking a object on the screen by mouse is a key point in design and implementing these system. The precision of mouse picking decides the performance of picture drawing and disposal. This paper presents a new method to pick up the 3D objects by mouse, which locates the object in 3D space by the ray. With this method, a satisfaction result is shown in the factual project.

摘要： 在三维图形环境以及其他的三维软件系统中，如何选取三维图形空间中的物体是设计三维图形环境的一个关键点。选取的精确程度往往决定了一个三维图形环境作图质量的高低。本文阐述了在三维图形环境软件设计中通过光线跟踪的方法来选取三维空间中的几何物体的方法。通过这种方法可以精确并方便地选择三维空间中的物体，在实际的工程应用中取得了很好的效果。