Marble/Runners/MarblePythonLoadingOSM

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Revision as of 18:46, 29 December 2013 by Benjaminkaiser (talk | contribs)
Loading OSM files in MarbleWidget
Tutorial Series   Marble Python Tutorial
Previous   Tutorial 4 - Loading KML files into Marble
What's Next   Tutorial 6 - Displaying a GeoData Placemark
Further Reading   n/a

Exporting OSM

Osm files can be used for creating small street maps or can be scaled to store streets worldwide. OSM files can be exported from OpenStreetMaps by clicking the export button as shown below.



Loading OSM files into a Marble Widget

Note
the documentation for the Marble Python bindings are currently not available online. They can instead be found in the source code at the location: src/bindings/python/html/marble/Marble.html.


Marble uses so-called runners to calculate routes, do reverse geocoding, parse files and search for placemarks (cities, addresses, points of interest, ...). This tutorial shows how to open a .osm file and display it into the Marble Widget.

#!/usr/bin/env python
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyKDE4.marble import *
import sys
import os

def main():
    app = QApplication(sys.argv)

    # check the file was loaded
    if(len(sys.argv) < 2):
      print("Usage: python " + sys.argv[0] + " file.osm")
      return 1
    # load file
    inputFile = os.path.abspath(sys.argv[-1])

    print(inputFile)

    # create the marble widget
    marble = Marble.MarbleWidget()

    # resize the widget and add a window title
    marble.resize(800, 600)
    marble.setWindowTitle("my_marble")

    # Load the OpenStreetMap map
    marble.setMapThemeId("earth/openstreetmap/openstreetmap.dgml")

    # center on Bucharest and Zoom
    marble.centerOn(Marble.GeoDataCoordinates(77.5674, 12.9782, 0, Marble.GeoDataCoordinates.Degree));
    marble.setZoom(3000)

    # add the kml file to the model
    marble.model().addGeoDataFile(inputFile)

    # add the widget to the KMainWindow
    marble.show()

    # run the app
    app.exec_()

main()

Copy and paste the code above into a text editor. Then save it as loading_osm.py and run it with:

python loading_osm.py some-file.osm

You should get a Marble Widget which displays your OSM file. For example, download and unpack Map.osm (a LinearRing representing Bangalore city junction), place it in the same folder as your loading_osm.py file and run python loading_osm.py map.osm. The result should be similar to this (note the map may reset the zoom level when it adds the .osm file data):



The placemarks on the map are clickable and trigger a dialog. The screenshot below is of the dialog of Bangalore City Station triggered by clicking it on the map.



Note
If you provide maps in your application please check the Terms of Use of the map material. The map material that is shipped with Marble is licensed in the spirit of Free Software. This usually means at least that the authors should be credited and that the license is mentioned. E.g. for OpenStreetMap the license is CC-BY-SA. Other map data shipped with Marble is either public domain or licensed in the spirit of the BSD license.