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Mercator Puzzle

gmaps-samples.googlecode.com

81–90 of 96 posts

Re: Mercator Puzzle

#81
post #39
post #16

Earlier quoted context omitted.

I had a hard time finding Ukraine, Thailand was also slightly hard to place pixel-perfect !

Took me a couple tries to get Thailand, too, as it didn't snap to the map the first time I placed it. A version with all countries would be an interesting teaching tool, to learn about geography and cartography. Would need to option to display only some countries at a time, to avoid overwhelming the user.

Stuck on not finding S. Africa

Re: Mercator Puzzle

#82
post #79

That was boss, "only" took me a 30-minutes! Well done and great for learning geography.

Seriously 30 minutes? Is this an American thing? To my mind almost all of them were obvious from the shapes alone (the one with straight edges wasn't, but the very fact that its borders are straight lines tell you there's only a few parts of the world it could be in).

Straight line border segments for nations seem to correlate well with borders determined by treaties between colonial powers.

Dragging all the red outlines to the equator was a big help.

Initial placement of red outlines in oceans might make the goal more obvious from the initial view.

A "satellite POV" might be interesting (same click&drag UI spins the earth/repositions the POV). The red outlines could then be placed in the empty corners.

Re: Mercator Puzzle

#83
This is an awesome UI concept that could be used to demonstrate other kinds of projections, too. It would be awesome to see similar apps related to perspective transformations, rectilinear vs. fisheye lenses, tilt-shift lenses, panorama stitching, etc.

Re: Mercator Puzzle

#84
post #21

Does anyone know why Google insists on Mercator projection? I guess that it makes the implementation bit simpler, but on the other hand you'd imagine that if anyone then Google would have the resources to use some more reasonable projection for greater good.

Google Earth uses a completely different (and superior) system, however it's more resource intensive.

TL;DR The Mercator projection is a solution to a problem that does not exist in Google Earth.

Projections, Mercator included, are ways to map a 3D shape (the globe) onto a static 2D surface (a map). Google Earth uses a dynamic 2D surface (a screen) to display a changing view of a 3D object. See TL;DR.

Re: Mercator Puzzle

#85
Fantastic! I learnt something new today. I did not know that the world was projected using Mercator projection and the how that played a role in distortion of the land size.

Re: Mercator Puzzle

#86
post #79

That was boss, "only" took me a 30-minutes! Well done and great for learning geography.

Seriously 30 minutes? Is this an American thing? To my mind almost all of them were obvious from the shapes alone (the one with straight edges wasn't, but the very fact that its borders are straight lines tell you there's only a few parts of the world it could be in).

Please don't make it a "my country vs. your country" thing. Some people have more aptitude for geography than others; it doesn't much matter where they are (as long as some schooling exists). I'm American and didn't have any trouble.

And who said the GP was American, anyway?

Re: Mercator Puzzle

#87
post #81
post #39

Earlier quoted context omitted.

Took me a couple tries to get Thailand, too, as it didn't snap to the map the first time I placed it. A version with all countries would be an interesting teaching tool, to learn about geography and cartography. Would need to option to display only some countries at a time, to avoid overwhelming the user.

Stuck on not finding S. Africa

South Africa was hard, but the hole for Lesotho was the big tip off for me.

Re: Mercator Puzzle

#88
post #30

Earlier quoted context omitted.

Not sure if this makes sense, but couldn't they have different projections for different zoom levels?

Yes, e.g. http://cartography.oregonstate.edu/demos/CompositeMapProject...

It messes up around Antarctica, but it works much better than mine, which doesn't even exist, so I should probably be quiet.

Re: Mercator Puzzle

#90
post #55

Earlier quoted context omitted.

I understand that Mercator isn't the most accurate representation, but seriously, "greater good?" There are a lot of things that I think Google can do "for greater good," and changing how they show a map isn't even in the first hundred pages.

The bang for the buck is pretty good though. Most people don't own an Atlas anymore. In the public consciousness Google Maps is the world map. If choice of map projection is important anywhere (which is debatable), it's important on Google Maps. And remember: you can always fail over to Mercator.

Map projections are part of the technological infrastructure of the world. Most people shouldn't have to worry, but someone needs to. What about calculating missile range? Or designing a tunnel that needs to be accurate to 1cm. Are your GPS surveys out by 30cm because you used a system that ignores continental drift. Or placing an oil rig in the wrong place in the sea due to a poor projection choice.
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