Visibility-Oriented Algorithms for Digital Terrain Models (Computer and Information Science)

数字地形模型的面向可见性的算法（计算机和信息科学）

• 批准号: 8704718
• 负责人: George Nagy
• 金额: $ 13.3万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8704718&HistoricalAwards=false
• 关键词: Visibility; Oriented; Algorithms; Digital; Terrain

The "visibility region" of a viewpoint on a surface is wll- defined. It contains all of the points that can be joined to the viewpoint by means of a line-segment that does not pass through the surface. In principle, the visibility region of every point on the surface can be computed. In practice, however, its computation must be approximated. In this research, the visibility regions of the n vertices of a Delaunay-triangulated terrain model are studied. A major goal of this research is to improve the average performance of known hidden-line and hidden- surface algorithms. This is accomplished by using several types of heuristics based on the unique characteristics of the problem. Algorithms will be developed to apply the resulting visibility maps to the location of observation points: to line-of-sight (television, fm, radar) communications and surveillance problems; to orientation and navigation; to data compression; and to the extraction of significant terrain features such as ridges and valleys. It is argued that the global nature of visibility model provides a useful alternative to partial derivatives for defining topographic entities. This research is expected to contribute to several areas including computational geometry, geographic information systems, and to computer communications.

表面上的视点的“可见区域”是wll- 定义了 它包含可以连接到 通过不穿过的线段的视点 表面上 原则上，每个点的可见区域 表面上可以计算。 但实际上，其 计算必须近似。 本研究 Delaunay三角网n个顶点的可见区域 研究了地形模型。 这项研究的一个主要目标是 提高已知隐线和隐线的平均性能， 表面算法 这是通过使用几种类型来实现的 基于问题的独特特征的分析方法。 将开发算法以应用由此产生的可见性 到观测点位置的映射：到视线 （电视，调频，雷达）通讯和监视问题; 定位和导航;数据压缩;以及 提取重要的地形特征，如山脊， 山谷 可见性模型的全局性 提供了一个有用的替代偏导数定义 地形实体 这项研究预计将有助于 包括计算几何学、地理学、 信息系统和计算机通信。