An automatic placement method for building annotations in a three-dimensional scene

Abstract

The invention discloses an automatic placement method for building annotations in a three-dimensional scene. According to the method, a candidate annotation set containing fixed-orientation annotations and dynamic-orientation annotations is constructed for each building model in a preprocessing stage according to geometric morphological characteristics of a three-dimensional building, and optimalannotations are screened according to an annotation evaluation algorithm related to viewpoints in an interactive browsing stage. And when the annotations are projected to the screen space conflict processing, the annotations are sequentially placed by adopting a greedy algorithm according to the global priorities of the annotations. Compared with the prior art, the method has the advantages that the real-time calculation amount is small, the dynamic change of the visual angle, the visual range and the visibility can be adapted, and the relevance between annotations and building elements is effectively kept. Besides, the annotations are sequentially placed according to the priority order through the greedy algorithm, the annotations which are close to the viewpoint, low in conflict degree and high in building significance can be reserved while screen space annotation conflicts are efficiently processed, and the readability of global annotations is improved.

Description

technical field [0001] The invention belongs to the fields of geographic information science and computer graphics, and in particular relates to a method for automatically placing building annotations in a three-dimensional scene. Background technique [0002] At present, related research on annotation placement on 2D maps and annotation placement in 3D scenes includes the following aspects: [0003] (1) 2D map annotation placement [0004] The automatic placement of text annotations has always been a research hotspot in 2D cartography. According to the types of elements to be annotated, map text annotations can be divided into point element annotations, line element annotations, and area element annotations. Research on 2D annotation focuses on the automatic placement of feature annotation. Edmondson et al. considered that the automatic placement of map annotations can be divided into three stages: candidate location generation, annotation location evaluation, and scheme ...

AI Technical Summary

Problems solved by technology

[0017] Purpose of the invention: Aiming at the defects of the existing methods for placing building annotations in 3D scenes, the present invention provides an automatic placement method for building annotations in 3D scenes, which can place building annotations in real time and efficiently during the browsing process, and solve the problem of Solve the problem of conflict between records, improve the readability of buildings in 3D scenes

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