Research And Implementation Of Annotation Processing Technology Based On Vector Tile Map

The history of the map is thick enough,from the Cuban clay map to today's digital electronic map,from the chart of Zheng He's voyages to the modern satellite navigation,the history of map development is the history of human courage and wisdom development;the historical development of the map It is also exciting enough,because the development of maps is closely related to the development of politics,military,economy and culture,and it is developing with science and technology.When using Internet maps today,in order to reduce the network bandwidth and make the map display more quickly and conveniently,we see a lot of pictures of the size of the entire screen.The map displayed on the screen is composed of multiple small images of the same size(usually 256 pixels*256 pixels)seamlessly spliced according to the established rules.These small pictures are tiles.Tiles are organized according to a pyramid hierarchy,and each tile can be uniquely tagged by level,row and rank.When panning the map and zooming the map,the browser acquires the tile vector data from the tile server,and draws and stitches the tiles.Vector tile data exists in vector form,recording target attributes and geometric information.Vector tiles are small and highly compressible,and are less constrained by network bandwidth overhead and storage space.However,there are still many problems with vector tile-based graphics technology.Map tiling poses a challenge to desktop software point annotation processing.Our processing of tile data annotations not only has important annotations,but also the gating and annotation between the annotation and target elements.In addition to the problem of gating each other,the tiling also brings the annotation to be incompletely displayed by the tile edge truncation,and the problem of duplicate annotation in multiple tiles.These problems have seriously affected the accuracy of map information expression.Therefore,we have an important significance in optimizing the processing of annotations.This paper explores the basic principles of annotation processing such as annotation position calculation method,position optimization strategy,annotation performance optimization strategy,and map tile annotation problem solving method.