In #foss4ge2025 I was talking about Mercator projection, and what is the difference with "Web-Mercator"

These images (at different zoom levels) show a loxodromic curve (at 45掳 N) in Web-Mercator (EPSG:3857) - that is a straight line in Mercator (EPSG:3395). In red the loxodromic or rhumline. In blue a straight line connecting the endpoints.

(To reproduce it in #QGIS, deselect "Clip features to canvas extent" for the affected layers as discussed in https://github.com/qgis/QGIS/issues/62654)

#gis #gischat

wanderer: Decentralized trail database: #wanderer by @flomp is a new, #opensource, #decentralized #trail database where you can upload tracks (or import them from #STRAVA or #Komoot), create or share routes, and connect with communities through #ActivityPub-powered #federation.
https://spatialists.ch/posts/2025/07/09-wanderer-decentralized-trail-database/ #GIS #GISchat #geospatial#SwissGIS

#NOAA Released the "beta" version of the Modernized National Spatial Reference System

https://beta.ngs.noaa.gov/

It will become the official CRS in the US, probably next year.
Everything is new: geographic system, vertical system, geoid model, state planes,... and to make it funnier, the geographic coordinates move between 1 and 2 meters respect to nad83 馃

If you want to play with it in PROJ, look at https://github.com/jjimenezshaw/NSRS-2022-PROJ

#gis #gischat

I found this lovely map "The World on a Quincuncial Projection", from Peirce (1879)

https://en.wikipedia.org/wiki/Peirce_quincuncial_projection

You can cut one square, bend the triangles/corners along the equator, and you have a two sided continuous map of the world. (also square)

#maps #gischat