Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Every map of China is wrong

medium.com

Post reply on HN
Print view View original

181–190 of 275 posts

Re: Every map of China is wrong

#181

Post by Propelloni »

rurounijones wrote: post #73
Reason077 wrote: post #21

Earlier quoted context omitted.

Indeed, despite its apparent illegality, China seems to be fairly well-supported and well-mapped by OpenStreetMap, at least in major cities. And is entirely mapped in normal WGS-84 without the obfuscation problem. In any case, according to Wikipedia, open-source code is available to convert between WGS-84 and the obfuscated GJC-02 coordinates. Since technology seems to have caught up with it, is there any advantage (…

> is there any advantage (military or otherwise) for China to persist with obfuscation? I don't think so but it would be an embarrassment for the government to admit it no longer serves a use and such an action would be anathema to them.

Why would it be an embarrassment to say something has outlived its usefulness?

Re: Every map of China is wrong

#182

Post by bdd8f1df777b »

jmprspret wrote: post #175
bdd8f1df777b wrote: post #174

Earlier quoted context omitted.

Can anyone point me to an open source implementation converting GJC-02 to WGS-84? The next time I debate with my Chinese peers on why this obfuscation is stupid, I need a reference. And to answer your question, it's because anyone proposing to break away from the current model will be accused of being a Western agent.

https://news.ycombinator.com/item?id=40220072

So it is https://github.com/googollee/eviltransform

Re: Every map of China is wrong

#183

Post by t-3 »

Propelloni wrote: post #181
rurounijones wrote: post #73

Earlier quoted context omitted.

> is there any advantage (military or otherwise) for China to persist with obfuscation? I don't think so but it would be an embarrassment for the government to admit it no longer serves a use and such an action would be anathema to them.

Why would it be an embarrassment to say something has outlived its usefulness?

Changing it could mean they made the wrong decision in the first place, which could make Important People lose face by possibly being at fault. Of course, they could try to present things in a different way, but potentially inviting criticism by rectifying mistakes isn't going to be looked upon warmly unless the people involved are all dead or out of favor.

Re: Every map of China is wrong

#184

Post by lainga »

bee_rider wrote: post #63
javajosh wrote: post #30

Earlier quoted context omitted.

Yes, I'm sure obfuscating Google Street maps will prevent DPR artillery from accurately striking targets in Seoul.

On one hand, I’m quite sure South Korea’s government has put a whole lot more thought into this than we have, and they decided to obfuscate the maps so… who knows, I guess they decided it helps. On the other hand, given that NK is using, what, WW2 vintage artillery, I can’t see how. They are probably aiming “south” with magnitude “lots,” right? What good is a 500 meter offset, or whatever, going to do when they are j…

On the third hand, if you've ever had to interact with a Korean bank over the internet (or read any of the laws that constrain this interaction), then yes,

> South Korea’s government has put a whole lot more thought into this than we have

in approximately 1998. and then never again. if it's not broken (for the chaebols), well...

Re: Every map of China is wrong

#185

Post by grotorea »

sib wrote: post #54
lolc wrote: post #13

Earlier quoted context omitted.

Thanks for the details. It is always interesting how the most innocent things are seen as danger by an autocracy.

For many years, the most accurate (paper) maps of the Soviet Union were those created by the CIA. The USSR's own maps included lots of intentionally incorrect data.

Funny since the USSR spent quite a lot of effort making good maps of other countries.

Re: Every map of China is wrong

#186

Post by planede »

mopsi wrote: post #165
_xnmw wrote: post #99

Earlier quoted context omitted.

Pretty insane for you to believe that a foreign country from afar could produce mapping data with the same degree of accuracy, detail and realtime freshness as a local provider on the ground. Of course there's military value in protecting mapping data from foreign adversaries, at the very least it adds a a time delay and some uncertainty to the data. It also probably makes it harder for some unsophisticated terrorist…

There's no need to speculate. Even with 1960s tech and no physical access, the US military somehow managed to produce really good maps of the USSR, superior to those that were available to the public. So ironically, the intentional inaccuracy of USSR-made maps affected domestic users the most. In 2024, with satellites producing imagery in ~10 cm resolution, the most important factor determining the quality of maps is…

The images might have ~10cm resolution, but that doesn't necessarily mean that there can't be larger scale systematic offsets and other distortions for larger tiles.

I recently learned that satellite images are often corrected to match known maps.

https://www.youtube.com/watch?v=PVemGumEEgo

Re: Every map of China is wrong

#187

Post by gwill »

ipnon wrote: post #112

Medium is not the best place to host your writing. I didn't even read the article because more than half of my screen was taken up by the Medium call-to-action and the Google account modal. Does anyone remember when a webpage just loaded a document?

i use reader mode in firefox/safari/orion.

Re: Every map of China is wrong

#188

Post by sumedh »

_xnmw wrote: post #99
deanresin wrote: post #71

Earlier quoted context omitted.

Pretty insane for the writer or even China/Russia to believe the US, with all of its resources, wouldn't be able to make their own accurate maps.

Pretty insane for you to believe that a foreign country from afar could produce mapping data with the same degree of accuracy, detail and realtime freshness as a local provider on the ground. Of course there's military value in protecting mapping data from foreign adversaries, at the very least it adds a a time delay and some uncertainty to the data. It also probably makes it harder for some unsophisticated terrorist…

> Pretty insane for you to believe that a foreign country from afar

US spy satellites can take sharp pictures which look they were taken by a drone is flying close to the ground.

Re: Every map of China is wrong

#189

Post by andy_ppp »

Reason077 wrote: post #21
lolc wrote: post #6

So Openstreetmap must be illegal in China! And indeed it is: https://wiki.openstreetmap.org/wiki/China Of course that doesn't stop people from mapping every bench in China https://www.openstreetmap.org/search?query=China#map=3/33.99...

Indeed, despite its apparent illegality, China seems to be fairly well-supported and well-mapped by OpenStreetMap, at least in major cities. And is entirely mapped in normal WGS-84 without the obfuscation problem. In any case, according to Wikipedia, open-source code is available to convert between WGS-84 and the obfuscated GJC-02 coordinates. Since technology seems to have caught up with it, is there any advantage (…

I think it’s always the problem with a closed system, there’s no way for some better decision making to happen. The very idea that obfuscation of maps will help China be more secure or competitive is absolutely absurd.

Re: Every map of China is wrong

#190

Post by barrkel »

Reason077 wrote: post #21
lolc wrote: post #6

So Openstreetmap must be illegal in China! And indeed it is: https://wiki.openstreetmap.org/wiki/China Of course that doesn't stop people from mapping every bench in China https://www.openstreetmap.org/search?query=China#map=3/33.99...

Indeed, despite its apparent illegality, China seems to be fairly well-supported and well-mapped by OpenStreetMap, at least in major cities. And is entirely mapped in normal WGS-84 without the obfuscation problem. In any case, according to Wikipedia, open-source code is available to convert between WGS-84 and the obfuscated GJC-02 coordinates. Since technology seems to have caught up with it, is there any advantage (…

It creates a legal fig leaf for the usual Chinese protectionism.
Post reply on HN