11.5.2.7 Polygon Class

Contents

A Polygon is a planar Surface representing a multisided geometry. It is defined by a single exterior boundary and zero or more interior boundaries, where each interior boundary defines a hole in the Polygon.

Polygon Examples

On a region map, Polygon objects could represent forests, districts, and so on.

Polygon Assertions

The boundary of a Polygon consists of a set of LinearRing objects (that is, LineString objects that are both simple and closed) that make up its exterior and interior boundaries.
A Polygon has no rings that cross. The rings in the boundary of a Polygon may intersect at a Point, but only as a tangent.
A Polygon has no lines, spikes, or punctures.
A Polygon has an interior that is a connected point set.
A Polygon may have holes. The exterior of a Polygon with holes is not connected. Each hole defines a connected component of the exterior.

The preceding assertions make a Polygon a simple geometry.

Find a PHP function

Document created the 26/06/2006, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/mysql-rf-gis-class-polygon.html

The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.

References

Manuel MySQL : https://dev.mysql.com/

These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.

Contents Haut