Difference between revisions of "Creating KML Files"
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| + | Use the '''Navigation Controls''' or your mouse to zoom in to a location. If you are unfamiliar with navigation in Google Earth, take a moment to go through the [[http://support.google.com/earth/bin/answer.py?hl=en&answer=176674 Navigation in Google Earth tutorial]]. | ||
=Create a Placemark= | =Create a Placemark= | ||
Revision as of 20:11, 13 January 2013
Contents
Introduction
This tutorial covers the basics of creating KML files. We will be using Google Earth to create KML files containing points, lines, and polygons, the three basic geometries involved in vector-based GIS.
Description of geometry types
A quick description of the basic geometry of GIS will be helpful.
There are three primary geometric types in most GIS applications.
Point
A point is a single 'spot' in space. It has no dimension, i.e. no length, width, or height. Points are typically defined by a set of coordinates, also known as a coordinate tuple. Two examples of coordinate sets include:
- (X, Y)
- (X, Y, Z)
Further reading: [Wikipedia: Point]
Line
A line is built of points. A sequence of points will form a line. For example:
- ((X, Y), (X, Y), (X, Y))
Further reading: [Wikipedia: Line]
Polygon
A polygon is similar to a line, except that its start and end points are the same. In effect, polygons are closed loops. Polygons form an area, and can have loops cut out of them.
Further reading: [Wikipedia: Polygon]
Install Google Earth
Skip this step if you already have Google Earth installed.
Zoom to an Area
Use the Navigation Controls or your mouse to zoom in to a location. If you are unfamiliar with navigation in Google Earth, take a moment to go through the [Navigation in Google Earth tutorial].
