Since the release of QGIS 1.8, Plugin Installer no longer includes the “add 3rd party repositories” button. This was an intentional design choice!
The new official plugin repository at plugins.qgis.org keeps everything in one place making it easier for users to find documentation and report issues. It will also provide many long-wanted features such as a rating system for plugins. You can already sort by number of downloads to discover the most popular plugins.
Last but not least: New users will not be able to discover your plugin if it is not in the repository.

Go ahead to plugins.qgis.org and upload your plugin now!

Easy Rectangles, Circles and Ellipses in QGIS

2011-10-21

“Rectangles ovals digitizing” plugin by Pavol Kapusta adds editing tools that make it really easy to create rectangles, squares, circles and ellipses. These are the tools provided by the new plugin:

Tools in "Rectangles ovals digitizing"

Give it a try!

Fast SQL Layer for QGIS

By underdark

2011-05-25

GIS, PostgreSQL, QGIS, SpatiaLite

5 Comments

For everyone working with spatial databases in QGIS there comes a time when “Add PostGIS/SpatiaLite Layer” and “RT Sql Layer” start to be annoying. You always have to retype or copy-paste your SQL queries into the user interface if you need to change the tiniest thing in the layer’s definition.

This is where “Fast SQL Layer” can be a real time saver. Fast SQL Layer is a new plugin for QGIS by Pablo T. Carreira. It basically adds an SQL console for loading layers from PostGIS/SpatiaLite into QGIS. And it even comes with syntax highlighting!

Installation

Fast SQL Layer comes with one dependency: Pygments, which is used for syntax highlighting.

On Ubuntu, all you have to do is install it with apt-get:

sudo apt-get install python-pygments

For Windows with OSGeo4W, @Mike_Toews posted this on gis.stackexchange:

I downloaded and extracted Pygments-1.4.tar.gz, then in an OSGeo4W shell within the Pygments-1.4 directory, type python setup.py build then python setup.py install

Usage

When you activate the plugin in plugin manager, a dock widget will appear which contains the console and some fields for specifying the database connection that should be used. Then, you can simply write your SQL query and load the results with one click.

Fast SQL plugin

In this example, I renamed “gid” to “id”, but you can actually edit the values in the drop down boxes to adjust the column names for id and geometry:

A second layer loaded using Fast SQL plugin

It certainly needs some polishing on the user interface side but I really like it.

How to Sort a Shapefile by Attributes

By underdark

2011-01-20

GIS, QGIS

If you ever need to sort the entries in a shapefile by one of its attributes, you might be happy to learn that somebody already did all the work for you and wrote a plugin for QGIS that can perform such sorting tasks: MMQGIS Sort plugin by Michael Minn

MMQGIS Sort plugin

Creating Cartograms with QGIS Cartogram Creator

By underdark

2010-11-13

GIS, QGIS

A cartogram is a map where some variable (e.g. population) is substituted for land area or distance. The geometry of the map is distorted to convey the information of this variable.

“Cartogram Creator” is a Python plugin for QGIS available through Carson Farmer’s repository.

Cartogram Creator icon

To use this plugin, you need a polygon layer with the attribute you want to be represented in the cartogram. I’m using a small file of Austrian regions with population data:

base data (Austrian regions and number of inhabitants)

The small island in the north-east is Vienna, the Austrian capital. With more than 1.5 million inhabitants, it is the region with highest population. This fact should be visible in the resulting cartogram.

I chose to run five iterations of the plugin algorithm. The plugin allows saving of each iteration’s result. This is how the shape of the region changes through the iterations:

cartogram iterations (n=5)

We can see Vienna “growing”. The final result looks like this:

cartogram result after five interations

The cartogram shows pretty clearly that the Vienna region is home to a considerable population.

More Tools for QGIS with MMQGIS

By underdark

2010-11-12

GIS, QGIS

MMQGIS is a set of Python plugins for manipulating vector map layers in Quantum GIS. […] MMQGIS does offer some useful tools missing from native QGIS or common plugin sets …

Labels Layer example

MMQGIS currently contains the following tools:

Attributes Export to CSV File
Attribute Join from CSV File
Color Map (Well, that’s redundant now and probably better implemented in core QGIS.)
Create Grid Layer
Create Label Layer
Geocode from Google
Geocode from Street Layer
Gridify
Hub Distance
Merge Layers
Select
Sort
Text to Float
Voronoi Diagram

The project homepage is located at michaelminn.com.

Browsing Spatio-Temporal Data With QGIS Time Manager Plugin

By underdark

2010-09-30

GIS, QGIS, spatio-temporal data

1 Comment

The aim of Time Manager plugin for QGIS is to provide comfortable browsing through temporal geodata. A dock widget provides a time slider and a configuration dialog for your layers to manage.