this post was submitted on 12 Feb 2025
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[–] [email protected] 76 points 4 weeks ago (2 children)

I believe that is 381 km squared, not 381 square kilometers. Vastly different areas. Germany is much larger than 381 square kilometers.

[–] [email protected] 33 points 4 weeks ago* (last edited 4 weeks ago) (3 children)

Oops. You are correct. Thank you. Fixing.

[–] [email protected] 11 points 4 weeks ago (2 children)

If it's a square 381km x 381km then that's 145161km² (and I'm not aware that there's any difference between "square kilometres" and "kilometres squared", is there?)

[–] [email protected] 5 points 4 weeks ago (1 children)

Square x and x squared is the same thing. The proper way to say this is "A square of 381 km width"

[–] [email protected] 3 points 4 weeks ago

It's very common to use km^2 (or m^2 or whatever) as a unit of area, with the understanding that a square with x km sides has area x^2 km^2. I can see what you're saying, but I think most people would call that area 'over 145 000 square km' or something, rather than talk about the side length.

[–] [email protected] 3 points 4 weeks ago

In writing it's not clear, but in spoken word you usually stress it like (381 kilometers) *pause* squared, which makes it clear the square applies to both value and unit, (381km)², whereas 381 (kilometers squared) is just 381km²

[–] [email protected] 4 points 4 weeks ago

The title still looks wrong to me

[–] [email protected] 1 points 4 weeks ago

Probably should take this post down, since it’s misleading.

[–] [email protected] 11 points 4 weeks ago

381^2^ k^2^m^2^

[–] [email protected] 35 points 4 weeks ago (2 children)

Some questions...

  1. How is this measured in sq km, rather than something digital such as pixels?
  2. Why is it 381? How did they arrive at that number?
  3. Why is there any limit at all, if it's this big?
[–] [email protected] 48 points 4 weeks ago* (last edited 4 weeks ago) (1 children)

Beginning with PDF 1.6, the size of the default user space unit may be set with the UserUnit entry of the page dictionary. Acrobat 7.0 supports a maximum UserUnit value of 75,000, which gives a maximum page dimension of 15,000,000 inches (14,400 * 75,000 * 1 ⁄ 72). The minimum UserUnit value is 1.0 (the default).

15 million inches happens to be exactly 381 km Source

[–] [email protected] 16 points 4 weeks ago (1 children)
[–] [email protected] 14 points 4 weeks ago

True. But thankfully most of the world uses centimetrs instead of inches nowadays. 😉

[–] [email protected] 30 points 4 weeks ago* (last edited 4 weeks ago) (1 children)

To satisfy the anything but metric postulate: 381 km originally are 15 million inches.

However, using some tricks, the size isn't limited to that.

https://alexwlchan.net/2024/big-pdf/

Remark: The side length of the square correspods to 381 km, subsequently, its area is 145161 km^2 .
381 km^2 are slightly smaller than the city of Cologne.

[–] [email protected] 8 points 4 weeks ago (1 children)

Good to see Germany won't run out of PDF for their digital mapping efforts and need a costly replacement.

[–] [email protected] 1 points 4 weeks ago

I'm pretty sure, we would use a costly alternative anyways.

[–] [email protected] 13 points 4 weeks ago (2 children)

Ok, now where can we get a printer to print that?

[–] [email protected] 3 points 4 weeks ago (1 children)

a global network of printers

[–] [email protected] 1 points 4 weeks ago

A national network will suffice.

[–] [email protected] 1 points 4 weeks ago* (last edited 4 weeks ago)

I think the play would be to get one that's modular (I suspect it's been done) and just keep building it out. The trick would be if the Earth is flat enough of it to sit nicely on. If not, you could cheat by slightly changing the DPI further from the center, so it would be a sphere section.

[–] [email protected] 7 points 4 weeks ago (1 children)

What is the smallest file size possible for a black PDF of this size? How about one with a solid color pattern, or a standard pattern?

[–] [email protected] 11 points 4 weeks ago* (last edited 4 weeks ago) (1 children)

Physical size is just a parameter, unless you insert formatting and stuff which needs to save data per page/region. Otherwise you can have just vector graphics of fixed data size which gets scaled on rendering to fit the physical limit.

[–] [email protected] 4 points 4 weeks ago (1 children)

So you could have a very small file that has a huge area, got it!

[–] [email protected] 1 points 4 weeks ago

easy to do in svg, just start with something like , then and you're mostly done; a gradient or pattern requires more than that, but vector graphics don't really care how large you say they are

[–] [email protected] 5 points 4 weeks ago

funny, because adobe illustrator shits itself at a couple m²

[–] [email protected] 1 points 4 weeks ago

DWG enthusiasts in tatters.