map

A few weeks ago while looking for a bridge's name, I found this website that lists all of the bridges in Amsterdam, with pictures!

The bridge I was looking for was unnamed and unnumbered at Van der Madeweg and Buitensinge but still listed on the site. The bridge had 1991 etched into it, from when it was constructed as part of the Southern branch of the Ringspoorbaan around Amsterdam, which opened in 1993.

This is an interesting project by David de la Iglesia Castro from Mozilla.ai on mapping in OSM using computer vision. Using a combination of YOLOv11 for object detection and SAM2 for segmentation they were able to map swimming pools from satellite imagery from Mapbox.

This isn't something completely new as Meta's RapidEditor for OSM is and to provide AI assistance. I have experience using Microsoft's GlobalMLFootprints model through RapidEditor while completing HOT tasks while impressive I disable it every time. There are always alignment errors, un-squared corners, false positives and overlapping polygons. Whenever a change is made by blindly accepting the AI recommendations it's obvious even without looking at the tags. Sometimes, it is more time-consuming to modify the changes than simply starting over.

The alignment and un-squared issues still seem to be present in David's project as seen from the screenshots. I haven't set up the project locally and the live demo was taken down after some discussion in the HackerNews comments. It was pointed out that the tool made it too easy for contributors to submit AI-generated submissions.

After OSM prides itself in quality submissions.

I don't want to take away from how impressive the work done was, as someone who has dabbled with YOLO and some mapping the source code seems approachable to tinker with.

Alex shares how to create static maps using Python and in doing so calculate a position on the unit square from coordinates. There's helpful Python code and a link to the OSM wiki describing the maths behind it. This was something I'd struggled to do when trying to add new points to the tiny-world-map. I was able to adjust the base map and add my own cities and plan to use this to add railway stations to the media map.

Rijkswaterstaat, part of the Dutch Ministry of Infrastructure and Water Management, plots gritters on a map along with data on total salt sprinkled and kilometers driven on the day and within the whole winter season. The map also shows the road surface temperature measured by 330 measuring points throughout the country. I originally discovered this site from their post on Mastodon.

Isochrone maps can be used to depict travel time from a specific point in a given region. Václav Volheijn takes this a step further and creates a spacetime map that distorts based on travel time. In their YouTube video, I made maps that show time instead of space, they go over the development process. The source code is also available on Github.

The author of TheCoffeeMachine gives a detailed walkthrough of how to add maps to a hugo site using uMap, which allows you to create maps based on OpenStreetMap (OSM) layers, and a shortcode that allows you to embed them. This is a belated TIL as I've already used this a few times, most recently for my post on the Tri-Country Train.

A rough overview of the steps involves signing up for and using uMap. This will allow you to create a map, set markers, and make the adjustments you need on top of existing OSM layer. From here using hanzei's hugo-component-osm theme you can embed the map into the hugo site using a shortcode. This includes passing in any parameters that uMap supports like coordinates to center the map and the zoom level.

I recommend reading the linked post for detailed steps. I needed to take this further and include a class within the iframe that's rendered on the page to able to style it with CSS. Unable to find a way to do this I forked and made my own addition. The pull request was created to the original repository if hanzei would like to include the changes. Here's a sample of what it looks like:

{< openstreetmap mapName="usa-train-lines-using-stadler-multiple-units_1100675" coordX="40.0731" coordY="-74.8924" scale="10" class="alignright" >}}

By using satellite images from Google in QGIS and marking areas of potentially good Christmas trees then exporting that layer and joining it with the National Forest Motor Vehicle User Map in Wherobots Cloud using Spatial SQL @lyonwj was able to map the areas with accessible roads.

Theres a lot of interesting bits to unpack there, but my main takeaway was the use of spatial SQL, it certainly beats relying on osmium tags-filters and manually editing GeoJSON files.

Based on OpenStreetMap data this map displays all country borders along with the 10,000 most populous cities. The file itself comes down to 628KB, which is impressive, allowing it to be cached on the client device. Different variants of this map are available with no country borders or fewer cities, to bring the overall size down. This can be used as a base map or a fallback map with leaflet. What I found interesting was looking into the code and seeing how the land areas were plotted and drawn, with the lakes then drawn above that and finally the cities after the lakes.

After discovering this, I've taken the opportunity to use it on my rail page to plot all the locations where I've filmed a video. At the time of posting this, it hasnt reached its final form yet but I'll be working on it over the coming days.