Re: [NTG-context] mp-geo Metapost package with ConTeXt

17 Jul 2021

      On 7/17/2021 12:20 PM, Henning Hraban Ramm wrote:
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Am 17.07.2021 um 11:53 schrieb Bruce Horrocks :
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On 16 Jul 2021, at 20:55, Hans Hagen  wrote:
On 7/15/2021 10:30 PM, Bruce Horrocks wrote:
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On 15 Jul 2021, at 18:58, Hans Hagen  wrote:
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I was wondering about that too. I admit that I looked into maps years ago but never could find quality data files.
Does this help?
https://www.naturalearthdata.com
i was halfway writing as reader for that fiel format when i noticed that is is also quite low res so i gave up on that and started playing (extending) with an more interesting alternative that mojca and i wrote years ago at a meeting
Off the top of my head I'm not aware of any higher resolution sources of global data - what scale were you thinking of?
Can you work with OpenStreetMap data?
https://planet.openstreetmap.org
http://download.geofabrik.de
https://download.bbbike.org/osm/
I didn’t find excerpts that only have e.g. country borders or rivers. But with usual XML tools you could extract those.
Indeed, that is what I was referring too. Mojca found this:

   https://osm-boundaries.com/

At a bachotex meeting (years ago, when the ctx group donated a nice 
roadmap display to the conference) we made an openstreetmap -> metapost 
style but afaik that never made it into a module. So, when I remembered 
that I updated it. I can now render my hometown (need to figure out 
colors) quite okay. (One can export an osm file in openstreetmap but 
with some limitations on size.)

I have to play a bit more with the style before I define it useable but 
the interface is liek this:

% where i live

\startMPpage
     draw lmt_openstreetmap [
         filename = "hasselt.osm"
         grid     = "dots",
     ] ;
\stopMPpage

% island in paris

\startMPpage
     draw lmt_openstreetmap [
         filename = "e:/tmp/map.osm"
     ] ;
\stopMPpage

The hasselt osm file is sime 12 MB, the colorful hasselt pdf file just 
below 1 MB so that's okay (3.7 sec processing time on my machine so if 
all claims are right sub seconds on a fast new apple).

Of course I need to make colors and what gets rendered configurable (via 
the interface). It's more about the fun aspect .. no need to typeset 
complete routes because that's what the web is for.

Hans

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