My OSM node density visualization has just been updated to show the freshest OSM data!
A significant difference from the 2014 edition is that the density is now calculated as OSM-nodes per m² on the ground (as opposed to nodes per projected pixel in the previous version). If you want to learn more about why this change makes a difference, I’d strongly recommend the following article by Christoph Hormann (imagico).
The updated slippy map lets you chose between the layers of different years (always created around end of June of each year) as well as a display of what changed during each 12 month interval. For example you can see that in North America, there were some imports as well as some major import-cleanups going on during the last year:
Last, but not least: you can now find the source code and instructions to generate all of this in the repository on github: https://github.com/tyrasd/osm-node-density/tree/gh-pages/code
議論
2016年07月 7日 17:40 imagico からのコメント
Very nice.
The difference layers are somewhat confusing color wise - showing a color scale there would be helpful.
2017年02月10日 17:37 joost schouppe からのコメント
Would it be very hard to get the node density of Europe on this grid? Would be kind of interesting to make a little analysis of the correlation between the two - and patterns of exceptions. Thinking about something like an analysis by clusters of squares like shown here (every slide adds or substracts 10% of the total European population)
2017年02月13日 13:30 tyr_asd からのコメント
@joost: nope. here you go: https://gist.github.com/tyrasd/80b2cbd9a3991e9b295124c1a6165bc2. Code and freshly processed raw data is included. osmnodes-eu.geostatgrid.csv uses keys that are compatible with the grid ids from the pop dataset, but note that their “reference grid” doesn’t include cells with 0 population.
2017年02月13日 13:41 joost schouppe からのコメント
Damn, there goes another week-end =) Thanks! Looking forward to playing around with this.
2017年04月11日 18:45 Jennings Anderson からのコメント
Martin, these are so cool!
I’m trying to re-run some of these with mbtiles and mapbox-gl for smooth zooming: http://www.townsendjennings.com/osm-node-density/#3.88/47.28/13.66
My resolution, however is nowhere as good as yours! What were the settings that you used when you generate your highest zoom-level png?
Thanks!
2017年04月12日 19:04 tyr_asd からのコメント
Jennings, I think I just run the commands as explained here (I’m not sure why it reads
zoom=16
here – this should also be15
or lower). That generates a 1 gigapixel (32768x32768) density map, which cut into tiles corresponds to max zoom level 7 on the slippy map: http://tyrasd.github.io/osm-node-density/#7/-7.961/-248.373/latest,placesI tried to use my tms tile source
https://s3-eu-west-1.amazonaws.com/osm-node-density/2016/{z}/{x}/{y}.png
with mapboxgl as well, and see similarly blurry results. Not sure what’s going on. Maybe it’s related to https://github.com/mapbox/mapbox-gl-js/issues/4552?2017年04月12日 21:02 Jennings Anderson からのコメント
Thanks Martin, that’s really interesting… staying tuned.