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When I make changes in OpenStreetMap, I often need to extract the object colour from a picture or a video, as example for a building, bench or a roof. This collides with a feature in KDE which I really like: Dim Inactive Windows.

The setting is in the KDE settings, under Desktop Effects -> Dim Inactive. As the name implies, it dims (makes them a bit more dark) all non-active windows - which makes it visually clear which window is currently active. Quite useful.

For picking a colour from a picture/video I’m using KColorChooser, which provides the colour in Hex code - exactly what I need in OSM.

However when KColorChooser is the active window, and all other windows are dimmed, it extracts the wrong colour from the picture/video - the colour which is already dimmed. Not what I need. Therefore when I do OSM edits, I temporarily disable this feature.

My kid got a new project: find fire stations. Google Maps is not really helpful here, obviously. And searching in the OpenStreetMap web interface is also a lot of work. But Overpass Turbo is able to find all the places.

When you open the Overpass Turbo page, it starts in Rome, Italy, at the Colloseum. That’s nice, but likely not the place you are looking for. Either scroll to the area you are interested in, or use the search function.

The left side of Overpass Turbo is the input field. You draft queries in a specific language, named Overpass QL (QL). Once you hit the Run button, the right side of the window either shows you the map, or the data output.

As reference for me: find benches with missing access tag in JOSM when editing OpenStreetMap:

As reference for me: find buildings with missing tags in JOSM when editing OpenStreetMap:

This posting is mainly a reference for myself, because I was looking for this specific issue a couple times.

OpenStreetMap (OSM) is a map of the world, created by anyone who wants to contribute. It so happens that data might be missing (just go and add it, if you see that something is not on the map). It also happens that someone adds too much data.

In 2019 I was in Cuba for a conference that took place there.

During the preparation of the trip it occured to me that internet access in the country is on the one hand slow and not well developed. On the other hand, that mobile internet access via roaming is obscenely expensive. It was foreseeable that I would have to do without mobile internet for a week, and consequently without online navigation. Preparations are in order.

These preparations were divided into two areas: before the trip and during the trip. For a while I thought about buying a map (this paper thing that you hold in your hand), but outside of Cuba you can’t find good maps for tourists which you can buy in advance. And the available maps looked rather outdated, and without enough details. As a result, I scratched this option from the list.

2019 war ich auf Kuba, für eine Konferenz welche dort stattgefunden hat.

Bei der Vorbereitung der Reise stellte sich heraus dass der Internetzugang im Land einerseits langsam ist, und nicht gut ausgebaut. Und andererseits dass der mobile Internetzugang über Roaming obszön teuer ist. Es war also abzusehen dass ich eine Woche ohne mobiles Internet auskommen muss, und demzufolge auch ohne online Navigation. Vorbereitungen waren notwendig.

Die Vorbereitungen teilten sich in zwei Bereiche: vor der Reise, und während der Reise. Kurz hatte ich überlegt ob ich eine Karte kaufe (dieses Ding aus Papier welches man in die Hand nimmt), aber es gibt außerhalb Kubas kein gutes Kartenmaterial für Touristen. Das was an Karten verfügbar war sah eher veraltet aus. Demzufolge habe ich diese Option wieder verworfen.

OpenStreetMap is an awesome project. Contributors constantly improve a online map and add new data, fix items in the map which did change in the real world, or improve the data for a number of projects (1, 2, 3, 4, 5, 6, List) building on top of the map. Being outside a lot, I figured that I can contribute as well. It’s just a question of how to transport the data from “out there” back to the laptop in my office. After probing around and trying a few tools, I came up with 3 different ways, depending on the situation and amount of changes.

What happens, if you ask the Chinese PostgreSQL community for a Meetup-like event, one or two speakers? You end up getting a full day conference ;-)

On September 12, Saturday, a full day PostgreSQL conference will take place at the Pivotal office in Beijing. If you want to attend, please sign up here.