Just a quick post here to say that I’ve added a new Projects page to my freelance website. I realised I didn’t have anywhere online that I could point people to that had links to all of the ‘non-work’ (maybe that should be ‘non-paid’) projects I’ve made. These projects include my Free GIS Data site, […]
I had a need to do some segmentation of some satellite imagery the other day, for a client. Years ago I was quite experienced at doing segmentation and classification using eCognition but that was using the university’s license, and I don’t have a license myself (and they’re very expensive). So, I wanted a free solution. […]
Recently I became suddenly curious about the sizes of buildings in Southampton, UK, where I live. I don’t know what triggered this sudden curiosity, but I wanted to know what the largest buildings in Southampton are. In this context, I’m using “largest” to mean largest in terms of land area covered – ie. the area […]
This is just a quick post to let you know that my Free GIS Data site is still going, and I’ve recently been through and fixed (or removed) all of the broken links. For those of you who aren’t aware of the site, it provides categorised links to over 500 sites which have freely available […]
A couple of weeks ago, I released the British Placename Mapper, which is a website that allows you to search place names in Great Britain and show them on a map. You can do searches like finding all the places starting with ‘great’, or ending with ‘burgh’ or containing ‘sea’. I tweeted and tooted about […]
Summary: You can use QGIS expressions to set the default path for an Attribute Form to be something like @project_folder || '/' || 'MapGraphs', which gives you a default path that is relative to the project folder but also has other custom subfolders in it. I spent a while redrafting the title of this post […]
I came up with an interesting plan for an artistic map recently (more on that when I’ve finished working on it), and to create it I needed to be able to calculate a large number of driving routes around Southampton, my home city. Specifically, I needed to be able to get lines showing the driving […]
As an Easter present for you all, I’ve got a new web app you can play with. It lets you search for UK place names – things like ‘ends with burgh’ or ‘starts with great’ or ‘contains sea’ – and then plot them on an interactive map. Once you’ve done that, you can even share […]
This is only about 3 years late – but I gave a talk at FOSS4G 2021 on geospatial PDFs. The full title was: From static PDFs to interactive, geospatial PDFs, or, ‘I never knew PDFs could do that!’ The video is below: In the talk I cover what a geospatial PDF is, how to export […]
Here’s a bit of SQL I wrote recently that had an error in it which I struggled to find. The error I got was ERROR: invalid reference to FROM-clause entry for table "roads" and I did some Googling but nothing really seemed to make sense as a cause of this error. My SQL looked like […]