Polygon compressing method and device

Abstract

The invention provides a polygon compressing method and device. When a polygon is determined as a complex polygon, the complex polygon is cut into a simple polygon, and the simple polygon obtained by cutting is subjected to triangle dissection to obtain triangles which form the simple polygon, and thus triangle cutting of the complex polygon is achieved. After the triangles which form the simple polygon are obtained, the triangles are subjected to triangular belt compression, and at least one triangular belt is obtained, wherein one triangular belt is used for storing N-2 vertexes of triangles, namely, more than three vertexes, and more than one triangle is obtained. For example, when the number of the vertexes stored by one triangular belt is four, two triangles can be obtained by decompression through stored four vertexes while six vertexes need to be stored for storing two triangles in the prior art. Therefore, the technical scheme provided by the invention can reduce the vertex data storage content and the storage space occupied by polygons.

Description

technical field [0001] The invention relates to the technical field of electronic maps, and more specifically, to a polygon compression method and device. Background technique [0002] The electronic map data at least includes: polygons, lines and points, wherein polygons are used to represent water areas, green areas, islands, roads, administrative regions, etc. in the real world. In order to improve the rendering efficiency of the electronic map, non-triangular polygons need to be divided into triangles in practical applications, but the inventor found in the process of researching the existing technology: [0003] First of all, the existing technology can only triangulate simple polygons, that is, the existing technology can only divide simple polygons into triangles, where, such as figure 1 Shown is a simple polygon, which means that the non-adjacent sides of the polygon do not intersect; [0004] Secondly, the existing technology needs to store each vertex of all tria...

AI Technical Summary

Problems solved by technology

[0003] First of all, the existing technology can only triangulate simple polygons, that is, the existing technology can only divide simple polygons into triangles, where, such as figure 1 Shown is a simple polygon, which means that the non-adjacent sides of the polygon do not intersect;

[0004] Secondly, the existing technology needs to store each vertex of all triangles obtained by segmentation, which will take up a lot of storage space and cause a waste of storage space

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