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Comment by atomwaffel | Hacker News Reader

It's used in what's arguably the most used map of our time, Google Maps (as well as most other interactive maps).

From the Google Maps & Earth Help Forum[1]:

> Why does Google maps use the inaccurate, ancient and distorted Mercator Projection?

> Maps uses Mercator because it preserves angles. The first launch of Maps actually did not use Mercator, and streets in high latitude places like Stockholm did not meet at right angles on the map the way they do in reality. While this distorts a 'zoomed-out view' of the map, it allows close-ups (street level) to appear more like reality. The majority of our users are looking down at the street level for businesses, directions, etc... so we're sticking with this projection for now.

[1]: https://productforums.google.com/forum/#!topic/maps/A2ygEJ5e...

And using something like Gall-Peters for an online map would be absolutely terrible except for mid-latitude countries (like North America). On a zoomable map, it's important to keep relative north-south and east-west distances very close to the same when zoomed in.

Seems to me that online maps should render the Earth as a sphere (or, heck, a properly shaped spheroid) centered on the viewport, where scrolling around rotates the sphere. This will look flat when zoomed in, will look accurate when zoomed out, and won't have any weird distortions of area or direction. I'm sure Google Maps didn't do it this way originally because it wasn't feasible when your minimum target was IE5 running on Windows 98, or whatever, but it surely could be done now.

Google Maps does do this in "Earth" mode (formerly "Satellite").

Nice! Is that new? If we could just get a Maps version of that view, it would be perfect.

I think it's best not to do it as a sphere as you suggest, as that would make it not feasible to use on low resource devices. Also, wouldn't work as well with the tiling approach.

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