笔式三维建模系统的隐式映射机制  

Implicit mapping mechanism in pen-based three-dimensional modeling system

作　　者：巩应奎[1] 范玉青[1] 吴志方 

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100083 [2]国家起重运输机械质量监督检验中心,北京100007

出　　处：《北京航空航天大学学报》2006年第5期603-606,共4页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家863高技术研究发展计划资助项目(2003AA411330);国家973重点基础研究基金资助项目(2002CB312103)

摘　　要：笔式三维建模系统支持用户基于纸笔隐喻自由勾画以表达三维模型,系统根据用户的交互意图完成相应的三维建模.针对笔式三维建模技术的交互特征,提出一种隐式映射机制.通过分析二维笔划以及交互的上下文,动态建立2个相互垂直的、虚拟的投影平面,从而将二维笔划信息平滑转换成三维空间信息.针对极限位置无法正常映射的情况,提出了一种坐标增量置换法来实现三维映射,不仅解决了极限位置的坐标映射,而且支持用户自由勾画更加复杂的三维模型.隐式映射机制将用户从繁琐、复杂的操作中解脱出来,集中精力关注创作灵感的表达.该方法已经在自主开发的笔式三维建模系统的原型系统PenSketch3D中得到验证,并取得了良好效果.The pen-based three-dimensional modeling system supports the user to sketch freely based on penpaper metaphor so as to express three-dimensional models, and carries out corresponding three-dimensional modeling according to the user＇s interaction intention. A kind of implicit mapping mechanism was proposed according to the characteristics of pen-based three-dimensional modeling technology. Two virtual projecting planes, which were vertical reciprocally, were constructed dynamically through analyzing the two-dimensional stroke and the interaction context so as to transform the two-dimensional stroke to three-dimensional spatial information smoothly. A method of coordinate increment replacement was proposed to dissolve the problems of mapping in ultimate positions. As a result, not only the problems of coordinate mapping from two-dimensional stroke to three-dimensional spatial information in ultimate positions were settled, but also the user could sketch more freely to express much more complicated threedimensional models. The user could be free from fussy and complicated operations by implicit mapping mechanism and concentrate on expressing his creative inspiration. It has been validated in a prototype system, PenSketch3D, with promising effect.

关 键 词：笔式用户界面 三维建模 隐式交互 人机交互 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]