Tag Archives: qgis
Georeferencing QGIS output rasters
Some of the design packages I rely on use very crude GIS facilities. In fact, all they can support is a georeferenced raster as a background image, so it’s more of a rough map than GIS. It helps if these … Continue reading
image georeferencing with QGIS
Quantum GIS (QGIS) has a very powerful image georeferencing module. What that allows you to do is convert screen pixels to a map of an area. The pixels could be from a scanned map or from a screen image. Scanned … Continue reading
current tools of my trade
Mark asked: What kind of GIS software are you using? Well, since you asked:- SpatiaLite: spatial awesome built on SQLite. I love it because I don’t need to play DBA. QGIS: for maps ogr: for file format futzing proj: for … Continue reading
ward maps: kinda working, sorta
Now I’ve sorted out formatting the labels and scraping the data, I should be almost ready to produce a pretty map. Well, almost. The DBF component of a shapefile seems somewhat resistant to adding a column, and SQLite doesn’t seem … Continue reading
closer to ward maps: scraping the data
Toronto publishes its candidates here http://app.toronto.ca/vote2010/findByOffice.do?officeType=2&officeName=Councillor in a kind of tabular format. All I want to do is count the number of candidates per ward, remembering that some wards have no candidates yet. Being lazy, I’d far rather have another … Continue reading
Labelling: harder than it looks
I’m rather taken with Mez’s rather neat Toronto ward candidate maps. I wonder if I could reproduce them (semi-)automatically? As a start, here’s the Toronto Wards layer, rendered in QGIS with the ward number as a label: You’ll notice that … Continue reading
tale of two cities: coordinate reference systems, and what on earth is the maywood tot lot?
For reasons that are not particularly clear, the Toronto.ca|Open data is in two different coordinate reference systems (CRS), MTM 3 Degree Zone 10, NAD27 (EPSG 2019) and UTM 6 Degree Zone 17N NAD27 (EPSG 26717). This confuses QGIS even if … Continue reading