Here is a quick handy tip if you are using GIT and want to be able to quickly diff or checkout the code base from a week, month etc. ago.
Posts Categorized: QGIS
A good quality world borders dataset
Some time ago I spent at least a day trying to find a good quality, free world political borders and coastlines dataset. Each product I found had some limitation – incomplete coverage or poor resolution. Today by happenstance a client pointed me to quite a good one.
Contrast and cartography – gdal_lightner
If you work with raster data in GIS you straddle a kind of wierd world where you deal with imagery but you cannot really manipulate the imagery as you would say with the GIMP or Photoshop. Conversely, if you ever tried to open a large GIS raster dataset with the GIMP you may have noticed… Read more »
Publishing multiple projects with QGIS Server
You know the drill right? You just made a beautiful map for your boss using QGIS Server. Then he walks into your office and says ‘Kiepie, I need another one in a different CRS’. Your heart drops in your chest and your jaw drops to the desk. You can’t do that using QGIS without publishing… Read more »
Simple binary raster reclassification in QGIS
The Raster Calculator in QGIS allows you to run any expression on a raster or collection of rasters. While it is definitely useful, exactly how to phrase your expression in order to reclassify a raster is not always clear. Let’s say you have a raster with values between 0 and 255, and you want everything… Read more »
Creating coloured rasters with GDAL
One of the most popular posts on my blog ever is my article about creating GDAL hillshades: ‘A workflow for creating beautiful relief shaded DEMS using GDAL‘. In the techniques outlined in the aforementioned article, colours are assigned across a continuum to and superimposed on top of a hillshaded model. The GDAL tools in QGIS… Read more »
Quick Git tip: blast from the past
This has been happening to me often lately: “Rats, this function is broken when I try to do XYZ. But why? I know it worked last week before I started messing around with it. I wasn’t testing the currently broken aspect of it in the interim, though, and I can’t remember what it looked like… Read more »
Vector transparency plugin for QGIS
Yesterday I wrote a new little plugin for QGIS. It is available here: http://plugins.qgis.org/plugins/VectorTransparency/ or if you prefer to get it from GIT then here: https://github.com/timlinux/VectorTransparency. You can also get the plugin by adding the new QGIS official repository (which will be available by default from QGIS 1.8 onwards) to your repository list: http://plugins.qgis.org/plugins/plugins.xml The plugin is very… Read more »
Remote debugging QGIS python plugins with PyDev
In two previous articles (one one using Eclipse to build QGIS, and the other on using Eclipse as a Django development platform), I mentioned I would delve a little into using the Eclipse environment as a platform for QGIS Plugin Development. In particular we are interested in using Eclipse as a remote debugging platform. What… Read more »
Upgrading a database to PostGIS 2
Recently I needed the function ST_Split for various and sundry reasons, only to discover that I couldn’t use it in my database. The reason was that ST_Split is a new function introduced in Postgis 2.0, and the database was still in 1.5.3. Obviously, time for an upgrade. I began following the upgrade process, which I’ll… Read more »