opensource

July 25, 2019

Offline hiking maps with QGIS 3 and Geopaparazzi

In this post, I will show how to export background maps (as a set of MBTiles files) from QGIS 3 and import them in Geopaparazzi on Android to serve as backup offline hiking maps when far from civilization and mobile coverage.

It can be useful in France, where interesting maps to have while hiking are the IGN ones like Carte Topographique IGN (Scan 25) or their standard map (Scan Express Standard). They are accessible freely through the Geoportail mobile app. Unfortunately, the app doesn’t support offline mode.

March 17, 2018

Freehand Raster Georeferencer plugin updated for QGIS 3

A few weeks ago, I updated my Freehand Raster Georeferencer plugin for the newly released QGIS 3. I also included a few fixes for some issues as well as new features such as uniform scaling, a new “Georeference with 2 Points” tool (contributed by a user) or taking into account an existing world file. Those changes were backported to the plugin version for QGIS 2 so there should not be any difference between the QGIS 2 and 3 versions. See the updated doc for information.

toolbar

July 22, 2016

"Freehand Raster Georefencer" plugin for QGIS

Some time ago, I released a plugin for QGIS called “Freehand Raster Georeferencer” that allows interactive raster georeferencing. It implements some tools (move, rotate, scale, stretch…) to manipulate a raster directly on the map, on top of the other layers. This is in contrast with the standard raster georeferencing tool of QGIS, which needs control points and then an export to be able to check the georeferencing.

November 19, 2014

Paris in 3D with QGIS and three.js

Some time ago, I saw this article about using the Qgis2threejs plugin to export a QGIS map as a 3D visualisation in the browser, thanks to three.js and WebGL. When I recently tried to follow the post to reproduce the results, I had some problem sourcing the data (related to Vienna, Austria) so instead I searched for data related to Paris to create a similar scene. Here is the result corresponding to the screenshot above and another one with aerial photos, both showing the Montmartre area of Paris.

September 22, 2013

QGIS 2.0

Version 2.0 of QGIS (formerly known as Quantum GIS) has just been released! The codename for this version is Dufour.

March 15, 2013

GAMA (GIS & Agent-based Modelling Architecture)

The “GIS and Agent-Based Modeling” blog reports on GAMA, an open source GIS-ABM tool that looks quite interesting:

GAMA is a simulation platform, which aims at providing field experts, modelers, and computer scientists with a complete modeling and simulation development environment for building spatially explicit agent-based simulations. It is being developed by several French and Vietnamese research teams under the umbrella of the IRD/UPMC International Research Unit UMMISCO since 2007.

March 22, 2012

New map styles from Stamen Design

I learnt today that Stamen Design have released new map styles for Open Street Map data. I really like the watercolor one, as it is quite different from what is usually seen on web maps.

February 10, 2009

AGS Touch: ArcGIS Server browser for iPhone/iPod Touch

I had been trying to get into iPhone / iPod Touch application development for some time, but I was just too lazy until I bought a few weeks ago an iPod Touch (which I really like - I am playing the Sudoku game from Mighty Mighty Good Games all the time).

May 1, 2008

Compiling Palo on Mac OS X

I am currently in the process of evaluating Palo for a personal project. The Palo server is an opensource (GPL) in-memory multidimensional database management system, well suited for OLAP. Jedox, the German makers of Palo, market it as a data store for Excel, but it should work well outside this specific usage scenario. They offer pre-compiled binaries for Windows and Linux but not for Mac OS X, so I set out to make one, which was not very hard. I outline the steps here. A downloadable package for Leopard is at the end of the post.