alt Hacker NewsI find it shocking that a reputable resource such as this is still displaying the size of Greenland or Africa wrong (Mercator projection) in relation to other land masses in its marketing material and documentation, like here. It just brings doubt to the whole project, which is a shame considering all the time they must have put in. Why show the map that way when majority of its users will never use it for nautical navigation? https://maplibre.org/maplibre-gl-js/docs/examples/display-a-...
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It's on our roadmap to support alternate projections, but as you can imagine it's a big project that so far nobody has been willing to pay for to implement unfortunately.
MapLibre GL JS does support globe mode. https://maplibre.org/maplibre-gl-js/docs/examples/display-a-... May we should update our examples to use globe mode when showing examples, especially those that show a world map. We will take that feedback into consideration!
You can use the Equal Earth projection with a plugin: https://equal.bbox.earth/maplibre-americas/
Web Mercator is the standard projection used on the web, if you think the we should use a different projection on the web then that's a completely separate argument
It's actually worse than that because the Web Mercator projection is unusable for navigation too - it doesn't preserve angles or area! (Angles are nearly preserved).
Well done Google. Slow handclap.
The NGA advised it's likely to cause geolocation errors of up to 40km near the poles:
https://www.gpsworld.com/nga-issues-advisory-notice-on-web-m...
Accuracy where it matters is why. Do you have a better suggestion for projecting a sphere onto a rectangle?
Web mercator is fantastic map. It's well known of course, so very helpful to orient. Plus, its square and easily tile-able, which is good for performance. Shapes of countries are preserved. Plus, the lines are straight, which works great for on screen. Neat and tidy.
Who cares Greenland looks big when zoomed out. "Mercator distorts size" is one of those gis-nerd idee fixes, the first factoid they learn in class, and it overwhelms all thought.
You're a bit hasty, for the users that needs mercator projections, they should be able to get it, see: https://maplibre.org/maplibre-gl-js/docs/API/type-aliases/Pr...
Because that's what everyone is used to.
Maplibre supports different projections if you want.
obligatory West Wing: https://www.youtube.com/watch?v=vVX-PrBRtTY
I’m not sure it’s very useful to rehash an argument with very tenuous relation to the OP here. The normal reason to use the Mercator projection in these situations is (a) it’s what people are used to and (b) it preserves angles so if you zoom in on a street then up will still be north and roads that are at right angles in the real world appear to be at right angles on the map. The latter property is pretty desirable and hard to achieve without doing some weird transition between projections as you zoom. This matters more for Europe (and I suppose parts of British Colombia) where there is a high population density at latitudes that are pretty extreme in much of the world.
I think Apple Maps has a pretty reasonable compromise here of transitioning from a globe to Mercator as you zoom, but this is a less nice UI with a mouse as you need to click to rotate the globe instead of pointing and zooming only. I don’t think there’s anything in this data that would make that unachievable – you just need to reproject the vector data a bit as you zoom out – but it takes some tricky mathematics to get right and so hasn’t been done yet.