PyTopo is a Python-gtk map viewer which interprets local tiled map data and displays it in an interactive viewer, where you can scroll to adjacent maps, switch between resolutions, or produce a map image for printing or editing.
Why does PyTopo exist? I needed a local, offline mapping program that worked on Linux.
I like to travel to remote locations with no network access, and of course I want maps once I'm there. When I first started PyTopo, smartphones didn't exist yet, and even in the smartphone age I often want a larger map than I can show on a phone screen, with a user interface that's easier to use for showing things like track logs.
Originally PyTopo was written to use data from National Geographic's commercial Topo! data CDs. Since then, it has expanded to use OpenStreetMap tiles as well as several other tile open sources. (Not Google Maps, since Google's terms of service doesn't permit other programs to use their tiles.)
Download: PyTopo hosted on Github.
There's a really old experimental MeeGo package for anyone interested in trying it, and I'd be interested to know if it works on other RPM platforms as well: PyTopo-1.0-1-beta1.noarch.rpm.
The first time you run pytopo, it will create a configuration file, typically ~/.config/pytopo/pytopo.sites (if it can't create that it will fall back to ~/.pytopo instead).
You might want to take a look at the file: this is where you can add additional map collections or sites you visit frequently. By default, pytopo will download OpenStreetMap tiles to ~/Maps. Of course, you can change that. See the PyTopo File Formats page for more details.
pytopo -p will print out a list of known sites.
With the initial default configuration you'll just have a few cities like
san-francisco, new-york, london, sydney;
this is mostly to show you how to add your own points of interest.
|Scroll the map in the indicated direction.|
|+/=, -||Zoom in or out.|
|s||Save the current map to a file under $HOME/Topo|
|Space||Print (to standard output) the current coordinates of map center.|
Clicking in the map displays the coordinates of where you clicked, as well as the distance and bearing from the last clicked point.
Dragging and mousewheel move and scroll the map, as you'd expect.
Click on a track or waypoint to select it and see what's known about it.
Right mouse click will bring up a menu offering other options.
Usage: pytopo site_name pytopo trackfile... pytopo [trackfile...] start_lat start_long collection pytopo -p Use degrees.decimal_minutes format for coordinates. Set up site names in ~/.pytopo Print list of known sites with pytopo -p Track files are GPX files which may contain track points and/or waypoints; multiple track files are allowed.
|San Francisco from the default setup.||Several tracklogs and waypoints hiking in the DOE-owned lands near White Rock, NM.||Tacklogs and waypoints above Lexington reservoir near Los Gatos, using USGS/Topo! dara|
Aside from OpenStreetMap data, pytopo can use local map data on disk or CD.
The Topo! local area and specific park map packages sold in camping/hiking stores (sometimes under the aegis of National Geographic) are reasonably priced as a source of map data. They come with Windows software, but Linux users can ignore the software and use the data files, which are standard GIF, named in a fairly straightforward way. They're a good source of US map data.
Caution: the Topo! Back Roads Explorer and the statewide explorer collections are not in this friendly format. They use large data files in a proprietary ".tpq" format. Tom Trebisky has analyzed the format and has written an extractor, and he also has a C GTK viewer for this format. (Eventually I hope to integrate direct support for them into pytopo as well.)
You can buy map bits directly from the USGS, but they have a hefty setup fee so it's not cost effective unless you're buying quite a lot.
For some areas, you can download topo maps; for instance, for California you can get maps in TIFF format from the California Spatial Information Library. You still have to split up the maps into maplets, though; if you have ImageMagick, you can use a command like
convert in-map.jpg -rotate 90 -crop 300x300 -repage +0+0 out-map%02d.jpg
Note: previously I included -trim as part of that line, and a lot of pages you'll find googling for image splitting will tell you to use -trim. Don't: it will give you maps of inconsistent sizes, and pytopo has no way to tell where the origin of the map should be.
A map split this way can be read with PyTopo 0.5 or later. Maps downloaded as PDF (such as USGS geologic maps) might work in imagemagick, but if not, try converting them to a raster format before splitting, using a program like GIMP or a command like
gs -sDEVICE=jpeg -r300 -sOutputFile=output-map.jpg input-map.pdf
If you want to contribute to PyTopo, or use the code for something else,
you'll probably want to know more about the classes it uses, in the
PyTopo API Documentation.
(This is generated with
epydoc --no-frames pytopo
and is not guaranteed to be up to date.)
I wrote some older commandline helper scripts, but honestly, I don't use them myself and don't vouch for them. I list them here merely on the chance that someone might find one of them a useful building block: