So, for those of you who haven’t seen it, SFCGAL, “a C++ wrapper library around CGAL with the aim of supporting ISO 19107:2013 and OGC Simple Features Access 1.2 for 3D operations” is now an optional include in PostGIS (I believe beginning with 2.1, forgive me if I’m wrong). This was a quiet outcome of the Boston Code Sprint, after Paul Ramsey declared exact rational number … Continue reading PostGIS with SFCGAL
In an upcoming recipe (another one for the cutting room floor), we’ll play a bit with realistic biking distances, as compared with a 5-mile buffer (light grey), a 5-mile driving distance (dark grey), and a 5-mile biking-on-roads-with-speed-limits-under-40mph (purplish). This is just a teaser for mapbaker… . Continue reading Realistic biking distances, pgRouting
Took me a while to post this, but Pete Warden DM’d me on twitter after this post: https://smathermather.wordpress.com/2013/10/01/geocoding-in-qgis-the-easy-way/ about geocoding with the following link: http://petewarden.com/2013/09/09/why-you-should-stop-pirating-googles-geo-apis/ It’s funny, I hadn’t given serious thought to whether this use of Google geocoding was a violation of the terms of service, but he makes some great points about why not only does it violate those terms, but why as advocates … Continue reading Pirating APIs
Search the Google for geocoding in QGIS and you find a few nice articles, mostly pointing to third party web sites that will geocode for you, e.g. this post from 2009. It’s a good post, but there’s an easier way now. Well, let’s see if a little SEO will help solve this for people– a great tool for geocoding in QGIS is MMQGIS. Add it … Continue reading Geocoding in QGIS, the easy way.
GitHub week for me: https://github.com/smathermather/pov-viewshed More to come, but in the meantime, enjoy. Continue reading pov-viewshed on GitHub
I am working on a project, well, I guess just read the README from the repo (a project which will require a creative rename in the future): https://github.com/smathermather/shape-pov shape-pov ATM, this is a script to write shapefiles to PovRay docs for rendering. Long-term, will be a map tile renderer with 3D support and more. Whats more? Well, while compositing in TileMill and all the Mapnik … Continue reading shape-pov on GitHub
I’ve shared bits and pieces of tree interpolation code (3D tree canopies from LiDAR) on this blog for a few years. I finally got things together enough to post some of this code on GitHub. Currently it has a LasTools dependency, so you’ll have to watch for that license gotcha, but I’ll be phasing out that dependency in future versions. In the future, I’ll do … Continue reading Tree Interpolator on GitHub
Last week, post Boston Code Sprint, I spent a couple of hours playing with bee data, specifically bee keeper data for Norfolk County Massachusetts. My friend Eric (a bee keeper of 4 hives in said county) says that worker bees can fly as far as 3 miles for nectar, but after that approximate limit, they hit diminishing returns relative to the calories they burn. Proximity … Continue reading Way beyond red-dot fever– bees hives and overlapping home ranges
Sadly, I cannot post the code for this one, but will post the images– playing with tesselation in PostGIS today: Continue reading Tesselation of Hexagons in PostGIS
The series and one additional example: Continue reading What is the center line of a complex polygon? Routing Stream and Rivers Part Two
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