42MapGenerator is a tiny bash script developed at School 42 (Paris) for downloading and generating maps of the real world, the Earth's moon and the planet Venus for the pedagogical project Fil de Fer (FdF).

It allows you to find by name the coordinates of a country or a city thanks to the Google Geocoding API and to reduce the exported file size by providing 5 different formats (XXL, XL, L, M, S).

It extracts topography data from 4 different providers:

• IGN (National Institute of Geographic and Forest Information / France), providing horizontal accuracy up to 250 meters of France and Overseas but excluding marine topography.

• NOAA (National Oceanic and Atmospheric Administration / USA), providing horizontal accuracy up to 1852 meters (1 arc-meter) of any region of the world but with a limited capacity of exported file size.

• MGDS (Marine Geoscience Data System / USA), providing an exceptional horizontal accuracy up to 100 meters of any region of the world, including marine topography but excluding some continental regions like Europe.

• USGS (Astrogeology Science Center / USA), providing planetary data with horizontal accuracy up to 100 meters of Earth's moon and Venus, derived from Earth-based & spatial missions photographs.

git clone https://github.com/jgigault/42MapGenerator ~/42MapGenerator

sh ~/42MapGenerator/42MapGenerator.sh

At first, you're asked to select an export directory in which to save the computed FdF maps. Then select a data provider and an available region of the world or a planet. Finally, choose a format and a mode of export of the marine's topography between flatten and keep data.

--no-update   // Do not check for updates at launch
--no-color    // Do not display color tags
--no-timeout  // Disable time-out for child processes

Add your options as arguments at launch:

sh ./42MapGenerator --no-update --no-timeout

• France Métropolitaine
• DOM-TOM: Guadeloupe
• DOM-TOM: Martinique
• DOM-TOM: Réunion
• DOM-TOM: Guyane
• DOM-TOM: Saint Martin - Saint Barthélémy

• Earth's moon
• Venus

• Whole world (MGDS only)
• Antarctic (MGDS only)
• Arctic (MGDS only)
• Europe (NOAA only)
• Alaska-Aleutians (MGDS only)
• Cascade Range (West Coast USA)
• Central America
• East African Rift System
• Eastern North American Margin
• Gulf of California
• Amazonia
• Cordillera de los Andes
• Izu-Bonin-Marinia
• Nankai
• New Zealand
• Papua New Guinea
• Red Sea
• Himalaya
• Mid-Ocean Ridges: EPR 8-11 N
• Mid-Ocean Ridges: JdF Endeavour
• Mid-Ocean Ridges: Lau Basin

Using NOAA or MGDS as data provider allows you to find by name a country or a city (MGDS only). The coordinates are requested through the Google Geocoding API.

Before downloading and generating a custom map, you can request for an online preview image through the MGDS portal which is opened in your default browser.

The pedagogical project Fil de Fer (FdF) consists in creating a C program that displays a graphical representation of a land. The program takes as first argument a path to a file which contains topography data.

A map for the project FdF is a simple text file based on the standard ARC/INFO Grid Format whose headers are removed.

Here is an ARC/INFO Grid sample file (header are the first 6 lines):

ncols         4
nrows         6
xllcorner     0.0
yllcorner     0.0
cellsize      50.0
NODATA_value  -9999
-9999 -9999 5 2
-9999 20 100 36
3 8 35 10
32 42 50 6
88 75 27 9
13 5 1 -9999

This type of topography data is available through GIS Web Services and several open data FTP servers.

• MNT BD Alti® IGN National Institute of Geographic and Forest Information / France (http://professionnels.ign.fr/bdalti)

• NGDC Grid Extraction Tool NOAA National Oceanic and Atmospheric Administration / USA (http://maps.ngdc.noaa.gov/viewers/wcs-client)

• GMRT Map Tool MGDS Marine Geoscience Data System / USA. Ryan, W.B.F., S.M. Carbotte, J.O. Coplan, S. O'Hara, A. Melkonian, R. Arko, R.A. Weissel, V. Ferrini, A. Goodwillie, F. Nitsche, J. Bonczkowski, and R. Zemsky (2009), Global Multi-Resolution Topography synthesis, Geochem. Geophys. Geosyst., 10, Q03014, doi: 10.1029/2008GC002332 (http://www.marine-geo.org/tools/GMRTMapTool/)

• USGS Planetary GIS Web Server USGS Astrogeology Science Center / USA (http://webgis.wr.usgs.gov/pigwad/down/index.html)

• Google Geocoding API (https://developers.google.com/maps/documentation/geocoding/)