No one uses a world map for navigation. Even when paper maps were still used, you would use it on a much smaller scale like a grid system. Even maritime maps would at largest only need to show an ocean.

It's much easier to accurately represent directions and proportional distances when you're not trying to fit the surface of a whole sphere onto one quadrilateral plane.

[–] zpiritual@lemmy.ca 5 points 5 days ago* (last edited 5 days ago) (1 children)

What? The projection matters on any scale and for navigational purposes will continue to use mercator projection on flat maps so there this decision doesn't change anything.

[–] wonderingwanderer@sopuli.xyz 0 points 5 days ago (1 children)

It really doesn't. On a ball as large as the earth, if you take a tiny section of it, it's basically already flat. You don't need to transform it mathematically to make it fit on a grid system.

Maybe you've never seen a map made for land navigation? They don't need to distort terrain feature size to make everything line up directionally.

[–] Axolotl_cpp@feddit.it 0 points 5 days ago* (last edited 5 days ago) (1 children)

Maybe you've never seen a map made for land navigation?

Can you share one or the name of the projection used? I am having an harf time searching for it

Edit: i found that for air navigation they use Lambert Conformal Conic, for marine they use Mercator and for land i found nothing which makes sense (and probably it would be Mercator anyway)

[–] wonderingwanderer@sopuli.xyz 2 points 5 days ago (1 children)

https://doc.esri.com/en/arcgis-pro/latest/help/mapping/properties/coordinate-systems-and-projections.html

A local coordinate system uses a false origin (0, 0 or other values) in an arbitrary location anywhere on earth. Local coordinate systems are often used for large-scale (small area) mapping. The false origin may or may not be aligned to a known real-world coordinate, but for the purpose of data capture, bearings and distances can be measured using the local coordinate system rather than global coordinates. Local coordinate systems are usually expressed in meters or feet.

Example:

https://slcprdpublicrecords.blob.core.windows.net/0001sjradmin/PDF/CB_1877_15_10045793.pdf

[–] Axolotl_cpp@feddit.it 0 points 5 days ago

Nice, thanks

[–] sem@piefed.blahaj.zone 1 points 5 days ago (1 children)

I want to contradict you slightly: people don't use world maps for navigation, but most are still using a world map projection, just zoomed in. Most map services like Google maps, mapquest, etc use something called the Web Mercator at all levels of zoom, i think because of the challenge of needing to zoom in anywhere on the map. I am not an expert on why they use the web mercator though.

[–] wonderingwanderer@sopuli.xyz 1 points 5 days ago (1 children)

I didn't say they don't use projections, I just said they don't use world maps. Localized maps are much easier to achieve accuracy of both distance and direction

[–] sem@piefed.blahaj.zone 1 points 5 days ago

Hence the clarification! They do use world map projections. I don't think they have to, but do for efficiency? Not an expert.