O'Reilly logo

Building Mapping Applications with QGIS by Erik Westra

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Adding lines and polygons

To add a LineString or a Polygon geometry, the user will draw the desired shape by clicking on each vertex in turn. Appropriate feedback will be displayed as the user clicks on each vertex. For example, a LineString geometry would be displayed in the following way:

Adding lines and polygons

To draw the outline of a Polygon geometry, the user will once again click on each vertex in turn. This time, however, the polygon itself will be displayed to make the resulting shape clear, as the following image shows:

Adding lines and polygons

In both cases, the basic logic of clicking ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required