Detection method and system for point to polygon position relation

Abstract

The invention relates to a detection method and system for point to polygon position relation. The method comprises the steps that a test point serves as an original point of an XY rectangular coordinate system, and coordinate values of all endpoints of a polygon are acquired; whether all the endpoints are located on the same side of the X coordinate axis or the Y coordinate axis of the XY rectangular coordinate system or not is detected according to the coordinate values of the endpoints; if not, Y coordinate values of the endpoints are traversed, and a new point set formed by endpoints meeting the relation that yi*yi-1 is smaller than 0 is acquired; straight lines of every two continuous points and a straight line of a head point and a tail point in the new point set are determined; whether the number of intersection points formed by the straight lines and the positive axis of the X coordinate axis is an odd number or not is judged; if the number is an odd number, it is judged that the test point is located in the polygon; if the number is an even number or the endpoints are located on the same side of the X coordinate axis or the Y coordinate axis, it is judged that the test point is out of the polygon. The scheme is suitable for detecting the point to concave polygon position relation and point to convex polygon position relation, containment is enhanced, and the advantages of high detection efficiency and detection accuracy are achieved.

Description

technical field [0001] The invention relates to the technical field of computer graphics, in particular to a method and a system for detecting orientation relationships between points and polygons. Background technique [0002] In technologies such as computer graphics, computational geometry, and geographic information systems, it is often necessary to determine the positional relationship between points and polygons. For example, in GIS applications, the geographical distribution of network elements (such as base stations, cells, etc.) of mobile communication equipment can be visually checked. When there is an alarm or fault caused by poor call quality in a certain area, the maintenance engineer will locate this area on the GIS, and circle a polygonal area, and then summarize and correlate the indicators of the cells in this area, and finally locate the The specific fault cell and the cause of the fault. This is a usage scenario that operators are very concerned about an...

AI Technical Summary

Problems solved by technology

If the cell within the polygon cannot be identified accurately and quickly, it will affect the maintenance engineer to locate the fault or even make a wrong decision

[0003] At present, the orientation method is generally used for convex polygons, that is, each edge of the polygon forms a directed vector, and then the left and right relationship of the test point in each vector is judged; for concave polygons, the ray method is generally used, that is, the number of times the test point intersects the boundary with each vertex To determine the internal and external relations, after analysis, this method has errors in special cases

[0004] In addition, it can also be judged by testing whether the sum of the angles between the point and all the vertices of the polygon is equal to 360 degrees, or whether the area of ​​the point and each side is equal to the area of ​​the polygon. These methods have certain theoretical and actual calculations that do not match situation, the actual calculation is difficult

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