三維電子地圖線要素注記自動配置研究.pdf

1、南京師范大學碩士學位論文三維電子地圖線要素注記自動配置研究姓名：索春婷申請學位級別：碩士專業(yè)：地理學;地圖學與地理信息系統(tǒng)指導教師：龍毅2009-05-24Abstract IIAbstract Abstract Map labeling is an important component of the map, which is the written language to express the name, quantity,

2、quantity characteristics of the geographical features. By means of the map labeling, the map readers can not only recognize the objects on the map, but also acquire the information related to the objects. With the develo

3、pment of the correlated science technology such as cartography, computer graphics and virtual simulation etc, 3-dimensional electronic map comes out and is becoming widely popular map products. But the problems of annota

4、tion placement occur in it, which has negative influence on the information extraction of the readers. After analyzing the research status of annotation placement in 3-dimensional electronic map, this article selects the

5、 3-dimensional line features as research objects. The line features is a class of important geographical features, whose graphics is relatively complicated. In the researches of automated map annotation, the annotation p

6、lacement of liner features plays an important role, which has greater difficulty and flexibility. The research on the automated annotation placement of line features in 3-dimentional map has great significance on the dev

7、elopment of 3-dimensional map as well as annotation placement of other 3-dimentional geographical features. The article makes summary of the home and aboard research status on the automated annotation placement of line f

8、eatures and introduces the basic knowledge of 3-dimensional electronic map. On the basis of it, it analyzes and classifies the morphological characteristics of line features. This article also raises the rules of annotat

9、ion placement of line features in 3-dementional electronic maps, discusses the methods of automated annotation placement, and makes detailed analysis and description of data pretreatment, automatic selection of annotatio

10、n positions, annotation conflicts and overlap. So the problem of occluded annotation in 3-demetional electronic map has been solved, which guarantees the visibility of the annotations; the annotation of invisible objects

11、 can be avoided, so the workload can be decreased and the work efficiency can be improved. Finally, by means of designing and developing prototype system, the raised methods above have been preliminarily verified and ana

12、lyzed; the advantages and disadvantages of the algorisms have been summarized. According to the existing and unsolved problems of the algorisms, the prospects of the research work on automated annotation placement of the