摘要
在矢量瓦片地图中,跨网格的要素被分割成多个部分,常常造成点、线、面要素中非均匀符号在网格边界处的不连续,这样不仅影响视觉效果,还容易引发空间认知错误。在保持矢量瓦片数据和样式独立的基础上,提出使用预处理和实时绘制相结合的方法解决这类问题。通过分析不同要素符号在网格边界不连续的类型和原因,提取了不同类型的绘图辅助信息;将绘图辅助信息作为客户端绘图参数来调整瓦片内符号单元的初始位置,从而实现要素符号连续性表达。该方案的有效性在大比例尺地图配图实验中得到了证明。
Objectives:Vector tile technology is considered as a new generation of Web map solution.Compared with raster tile,vector tile is more flexible.It renders the map based on vector data and preset styles on the client.Therefore,users can easily change map styles without reproducing tile data.However,in vector tile maps,the features that cross the grid are divided into multiple parts,which often cause non-uniform symbol discontinuities of point,line,and area features.It not only affects visualization effect,but also leads to spatial cognitive errors.Methods:On the premise of independence coordinate data and symbol style of vector tile,a schema combining preprocessing and real-time rendering is proposed to solve these problems.By analyzing the types and causes of discontinuity of different feature’s symbols at the grid boundary,drawing auxiliary information for different types of symbols is extracted,which is used to adjust initial position of symbol unit in the tile and to realize the continuous representation of symbols.Results:A prototype system based on this scheme was developed and a large scale map mapping experiment was performed.Experimental results show that the proposed method can solve the problem of symbol discontinuity at the grid boundary.Conclusions:The proposed method can meet the needs of vector tile production and drawing in terms of reusability and efficiency.
作者
刘鹏程
许小峰
杨敏
LIU Pengcheng;XU Xiaofeng;YANG Min(Key Laboratory for Geographical Process Analysis and Simulation,Central China Normal University,Wuhan 430079,China;School of Urban and Environmental Science,Central China Normal University,Wuhan 430079,China;Wuhan Natural Resources and Planning Information Center,Wuhan 430014,China;School of Resource and Environmental Sciences,Wuhan University,Wuhan 430079,China)
出处
《武汉大学学报（信息科学版）》
EI
CAS
CSCD
北大核心
2022年第3期455-462,共8页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(42071455,41871377)
中央高校自主科研项目(CCNU30106190454)
数字制图与国土信息应用工程自然资源部重点实验室开放研究基金(ZRZYBWD201909)。
