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All Maps in China are Transformed

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Re: All Maps in China are Transformed

#51

Post by marshray »

eob wrote: post #50

Here's a completely anecdotal, "a friend of a friend.." story, but I think it's a cool yi and you'll enjoy it: A friend of a friend is a cartographer who works in DC. According to this person, the official subway map of DC distorts the true geography of the city -- and the subway lines -- as much for security purposes as it does graphic design purposes. The red line, in particular, apparently is drawn with a complete…

Subway "maps" tend to be more like generalized graph diagrams than cartographically accurate maps. After all, you're stuck in a box and your only choice is which node to get off at.

But it wouldn't surprise me if an overlay on a cartographic map was intentionally inaccurate. One time I was in DC a cab driver was trying to get me to my hotel. His GPS went totally nonfunctional when we were in view of the Pentagon.

It would be an interesting research project to ride around subway systems with a data-logging accelerometer (like a smartphone). Integrate acceleration to get velocity, integrate velocity to get relative position, get GPS fixes when the signal is available, and diagram the results.

Re: All Maps in China are Transformed

#52

Post by jrockway »

yaix wrote: post #16
machinagod wrote: post #12

There's a couple of regulations for selling GPS enabled devices in China (I am a software guy on a major PND manufacturer with products being sold in China). - The map data is scrambled (GPS coordinates are encrypted). - To correlate a GPS position with the map data, you plug the HW position through an encryption library (which you have to compile in a specific government building in Beijing). - Border drawing is str…

Everywhere in China you can buy illlegally imported smartphones (cheaper, avoids chinese sales taxes) from Hongkong, all with GPS included.

One country, two systems.

Re: All Maps in China are Transformed

#53

Post by viraptor »

eob wrote: post #50

Here's a completely anecdotal, "a friend of a friend.." story, but I think it's a cool yi and you'll enjoy it: A friend of a friend is a cartographer who works in DC. According to this person, the official subway map of DC distorts the true geography of the city -- and the subway lines -- as much for security purposes as it does graphic design purposes. The red line, in particular, apparently is drawn with a complete…

Underground maps usually don't match the real geography. If you made a "real" map, it would be next to useless since the central stations should be all in one place with lots of empty space around. It's the destination / via station you care about when you know the destination, not realistic detail of the path itself.

http://en.wikipedia.org/wiki/Tube_map has some examples of more realistic London underground maps (older editions). It's a common topic of graphic design / visualisation courses.

Re: All Maps in China are Transformed

#54

Post by sunyc »

of course it is china only. in china licensed gps maker can buy a chip deal with the offset ,provided by government.

it is a non uniformed transformation.being applied to.whole map , to lower the accruacy.

Re: All Maps in China are Transformed

#55

Post by mrtron »

tokenadult wrote: post #42
est wrote: post #29

Earlier quoted context omitted.

> Tibet is of course China Do you guys put Tibet as disputed area on like 90% of the maps in the West? Really?

On most maps published in the West, Tibet is shown as an integral part of the territory of the People's Republic of China, even though plenty of Americans drive around with "Free Tibet" bumper stickers on their cars. That is the GOVERNMENTAL position of the United States at present, that Tibet is part of the territory of China. (Of course historical Tibet includes regions outside the current boundaries of the Tibet A…

Here is my perspective on Taiwan grossly simplified.

A bunch of Han Chinese moved to the island. The Dutch established a small colony there. Japan took over. Post-WW2 they were given independence from Japan. The pre-communist leader of China moved to Taiwan and took over politically. The KMT party ruled until recently, when Taiwan peacefully transitioned to a democracy and now has two main parties.

There is nothing in Taiwan under Chinese control. They have their own government, constitution, military, their own passports that are recognized worldwide, etc. However, there is a looming threat that China will attempt to take over which drives mandatory military service, and tight relations with the US.

Re: All Maps in China are Transformed

#56

Post by pyre »

narkee wrote: post #39
marshray wrote: post #30

Back in the early 90's (in the US) I had a friend who was a college student from China. In the common area of her dorm there was a huge wall-size Rand-McNally map of the world. We were looking it over. "There's China" I said. "And there's Taiwan." "You know Taiwan is really not that big." she said. "What do you mean?" "Map makers show it larger than it really is in order to exaggerate its importance." I was a little…

Are you suggesting that in this case the blogger is similarly misinformed or deluded? I don't think it's unreasonable to think that China is manipulating its map data, particularly when other people here in the mapping industry have already said this is well known in their field.

Seems more likely that Chinese maps make Taiwan smaller, and when people in China point to the differences between locally made maps and foreign maps, they are told that foreign map makers are playing some sort of anti-China political game.

Or, people have it ingrained in them that Taiwan is small, and they all know that Chinese map-makers are politically motivated, so they assume that all map-makers are equally politically motivated.

Re: All Maps in China are Transformed

#57

Post by nate_meurer »

rmc wrote: post #46
marshray wrote: post #30

Back in the early 90's (in the US) I had a friend who was a college student from China. In the common area of her dorm there was a huge wall-size Rand-McNally map of the world. We were looking it over. "There's China" I said. "And there's Taiwan." "You know Taiwan is really not that big." she said. "What do you mean?" "Map makers show it larger than it really is in order to exaggerate its importance." I was a little…

those would have to be accurate in order to function The most common form of map, Mercator projection, greatly distorts the area of land around the equator, and makes northernly (& southerly) lands appear much larger. It makes Canada, Greenland, Alaska, et al. appear quite large compared to Africa & South America. But those areas are much larger. http://en.wikipedia.org/wiki/Mercator_projection#Uses

Mercator distortion has nothing to do with the anecdote in the parent post. There the allegation was of deliberate inaccuracy, which renders a map non-functional for most purposes.

All 2D map projections produce either distortion or discontinuity. Neither of these affects a map's functionality in the way that outright inaccuracy does.

Re: All Maps in China are Transformed

#58

Post by nate_meurer »

FuzzyDunlop wrote: post #32
iloveponies wrote: post #5

Earlier quoted context omitted.

It's news to the rest of us who don't work in that world.

Requiring legitimate incorporation in a foreign country in order to do business there (typically through partnership with a domestic firm) is also not unique to China or map making.

No, but doing so in order to ensure state control of information for propaganda purposes is certainly a feature of tyrannical governments, China being a particularly strong example.

Re: All Maps in China are Transformed

#59

Post by pyre »

john_horton wrote: post #31

It seems like there is little tactical payoff in doing this, as large, foreign militaries would already have detailed, accurate maps covering the whole world, China included. I bet this is an internal-resistance oriented policy.

Even then, if there were an internal-resistance movement that was well organized enough, they could get around this stuff. Seems more like it's there to keep some bureaucrats employed and possibly to prevent lone-wolf resistance 'fighters' who might not be well organized/smart enough to get around these measures.

Re: All Maps in China are Transformed

#60

Post by slipperyp »

rmc wrote: post #46
marshray wrote: post #30

Back in the early 90's (in the US) I had a friend who was a college student from China. In the common area of her dorm there was a huge wall-size Rand-McNally map of the world. We were looking it over. "There's China" I said. "And there's Taiwan." "You know Taiwan is really not that big." she said. "What do you mean?" "Map makers show it larger than it really is in order to exaggerate its importance." I was a little…

those would have to be accurate in order to function The most common form of map, Mercator projection, greatly distorts the area of land around the equator, and makes northernly (& southerly) lands appear much larger. It makes Canada, Greenland, Alaska, et al. appear quite large compared to Africa & South America. But those areas are much larger. http://en.wikipedia.org/wiki/Mercator_projection#Uses

There are a bunch of parallel conversations spawned from this 2 year old blog post. For reference, here's the area the author talked about in current google maps:

http://maps.google.com/maps?q=Huashan+Road,+Shanghai,+China&...

The locations are all still off and they're consistently off by an offset throughout Shanghai. There might be some deliberate dishonesty by map makers in China, but I don't think this is evidence of it - I think this is just an inaccurate projection. If you want to make bad maps to confuse people - first, that's probably pretty impossible with current information systems, even in China, and second, this would be a really bad attempt at it.

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