用轨迹球实现地物化资料三维立体图的旋转

THE REALIZATION OF ROTATION OF GEOPHYSICAL AND GEOCHEMICAL 3D GRAPHICS BY USING ARC-BALL

为了从各个角度观察屏幕上的三维场景,可以通过鼠标的拖动来实现。通常的做法是使场景绕X、Y、Z旋转,但这样操作不方便,旋转效果不理想。有一种更好的方法是:为三维场景建立一个外接球,旋转外接球的同时旋转了球体内的三维场景,这种技术叫轨迹球技术。这里介绍了轨迹球技术的数学原理、计算方法,并用轨迹球技术在OpenGL环境下实现了地物化资料三维立体图的旋转,操作起来方便直观,人机交互体验良好。

In order to observe 3D graphics,we rotate the scene around X,Y or Z axis,however,it's hard to rotate to the precise position we want.There is a better way that we construct a sphere which contains all the objects in scene.The objects rotate with the rotation of the sphere,and we call this sphere as arcball.This paper introduces the theory of arcball and how to realize the rotation of 3D graphics of geophysics and geochemistry by using arcball.