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View Full Version : Map Inequality scene from "The West Wing"



the-golem
05-14-2014, 04:33 AM
I'm just goiing to leave this here. Discuss. :D


http://youtu.be/n8zBC2dvERM

Azelor
05-14-2014, 12:19 PM
I admit that Mercator have some issues but Peter also have it's own. So I can't say that Peter's projection is better but it's different and offer a different perception of the world. In that regard, it's a good idea to teach it in school with other projections as well.

waldronate
05-14-2014, 04:46 PM
I believe Hai-Etlik (and just about every other professional in the field) may have some things to say about the importance and applicability of the Gall-Peters projection. xkcd: Map Projections (http://xkcd.com/977/) and 977: Map Projections - explain xkcd (http://www.explainxkcd.com/wiki/index.php/977:_Map_Projections) can be of use here.

Gamerprinter
05-14-2014, 05:12 PM
Since I agree that a map of the world actually exists on a globe, so no 2D projection (while some are closer than others) get it right, I don't even think about this much at all. I don't think its the reason, but I never design worlds, only regions or smaller, because I don't need an entire world to display a setting I game in, so what the rest of the world looks like, in general, is completely meaningless to me. I don't mean I don't care about people or the fate of our world, just how it is depicted means nothing to me - I don't even think about it (unless exposed to a thread that discusses it.) :p

Hai-Etlik
05-17-2014, 04:16 AM
First off, stating something, or worse, just providing a link and then demanding that people "discuss" is rude. What's the point dredging this up again if you aren't even going to try to add something new? If you aren't going to "discuss" it why should we? Do you have an opinion? a question? any reason at all to post this?


I believe Hai-Etlik (and just about every other professional in the field) may have some things to say about the importance and applicability of the Gall-Peters projection. xkcd: Map Projections (http://xkcd.com/977/) and 977: Map Projections - explain xkcd (http://www.explainxkcd.com/wiki/index.php/977:_Map_Projections) can be of use here.

That something is along the lines of "Enough already!" Peters was an example of knowing just enough to convince others to fix a huge problem but not enough to realize that the problem doesn't really exist and his solution is crap.

Cylindrical equal area projections like Gall, LCEA, Hobo-Dyer, and Behrmann are a horrible choice for general reference use. They are no less distorted than Mercator or any other projection, they just change the type and location of the distortion.

There are other equal area projections that are far better at maintaining somewhat recognizable shapes for when you really need a global equal area projection. Generally I prefer Hammer, but it varies with the particular needs of the map. Equal area projections are generally required for statistical maps, not for general reference, and such maps are more common at larger scales where extent specific projections can be used.

For global reference maps like those in atlases and wall maps in schools, normal cylindrical projections like both Mercator and Gall-Peters were ditched ages ago in favour of compromise projections that try to balance and spread the distortion. Robinson and Winkel Tripel are most common now. If you find a school room with a Mercator map hanging on the wall, said map is probably so out of date that there are much bigger issues that areal distortion.

Mercator is used for web "slippy maps" because it genuinely is the best choice for a general purpose map that you can zoom and pan while covering the entire planet (except near the poles) When you are zoomed in far enough on it, you just need to apply a scale correction to get something very close to what you'd get with a projection specific to the zoomed in extent. Only Conformal ("angle preserving") projections can do that, and Normal Mercator is the only conformal projection that also preserves north (in fact it is the only projection of any sort that can globally preserve all compass bearings, which is precisely what is was designed to do. A cylindrical equal area projection would require isotropic image scaling (scaling vertical and horizontal differently) to achieve the same capability which would lead to lower visual quality and a great deal more complexity in web map software, or rendering in a varying projection to begin with, which prevents smooth panning.

Sorry if I'm being a bit blunt but both the "Discuss" thing and Arno Peters are among my pet peeves. Up there along side "I have a question..." and Homoeopathy.