| Popis: |
Given a map which describes an obstacle-cluttered environment, a number of different queries can be posed. Such queries may involve point-to-point visibility, shortest paths, general visibility from an arbitrary source-point or perhaps localization. Here, a localization query is defined to be the problem of describing the collection of all points which may be reached by moving away from some arbitrary source-point, in any direction, while not exceeding a given radius. The solutions to localization and general visibility queries are perhaps best presented graphically, i.e., in visual terms. For 2-D maps, this paper describes a unified approach for deriving solutions to the above-mentioned problems, including techniques for producing visual responses when appropriate. The methods described herein are founded upon a data abstraction known as a free-space graph. |
