User:NJR ZA/osm2svg

Introduction

I have been looking at converting Open Street Map [1] data to Usable Wikivoyage maps. This is still early days, but it seems to be a viable solution to quickly and easily generate maps for Wikivoyage articles.

To start with, I took osmarender 6.0 [2] from the OpenStreetMap project as base for a wikivoyage map generator

Status

• Almost Usable, but with a lot of restrictions and work that still needs doing
• It's only been tested on Ubuntu 7.10

Changelog

Version 0.01 to 0.04

• Initial messing about with the osmarender code to get to know what makes it tick, what it's short-commings are etc
• Added some of the wikivoyage symbols to use in rendering

A number of issues were clear from the start

• The generated svg files are far to big
• The code can be made a lot simpler
• OSM data is cc-by-sa, but there is no mechanism in osmarender to extract the user info for attribution
• Once a map has been rendered there is no easy way to edit it

Version 0.05 to 0.09

• added isWayVisible check to drop all ways that will not be visible on the rendered map from the generated svg. This makes the resulting svg a lot smaller and easier to work with
• added rendering of the wikivoyage annotation box, symbol box and license box
• added extract of individual OSM contributors for attribution
• added generation of wikivoyage wikitext at completion of conversion
• added initial support for themes (so this can be used for not only wikivoyage)
• added automated scaling of the non map elements so they match the size of the map
• added automated selection for the scale size
• added yards/miles as additional scale units to the existing meter/kilometer
• added a lot of useful progress output

Version 0.10

• added <locate centerlat="" centerlon="" width="" height=""/> that will allow one to specify a central location in decimal degrees and the height and width in km to render at that location
• cleaned up the documentation render area selection
• fixed a bug introduced in 0.09 causing isAreaVisible to return false negatives
• fixed small spelling mistake on output
• removed external wikilinks to OSM users, Wikivoyage does not like multiple external links

Version 0.11

• better scale size selection
• code cleanup

Software overview

The current code consists of

• osm2svg.xsl - The main translator, based on osmarender.xsl from Osmarender 6.0 Alpha 6
• osm2svg.xml - Conversion rules used by osm2wtmap.xsl. Based on osm-map-features-z16.xml from Osmarender 6.0 Alpha 6
• themes/themePostMessage.xsl - some code that can be executed at completion of the conversion. Used by the wikivoyage theme to generate wikitext that can be used for attribution and image description when uploading the map to the wiki
• themes/wikivoyage/css.xml - stylesheet for wikivoyage
• themes/wikivoyage/markers.xml - markers for wikivoyage
• themes/wikivoyage/patterns.xml - patterns for wikivoyage
• themes/wikivoyage/symbols.xml - symbols for wikivoyage

The latest version is available here

ToDo list

Look and feel changes

• CSS needs to be updated to match recommendations given in Project:How to draw a map
• all wikivoyage symbols need to be added

  Mostly done now

• rules need to be changed so they always refer to a standard set of symbol names that can be reused in all themes
• A zoom factor needs to be added in order to selectively apply rules depending on map size
  • rules need to be changes to cater for this and rules from the other osmarender zoom levels need to be added to the current rule set
• map element scaling (road width and spacing between roads etc) need to be calculated automatically based on map size, as has been done for the non map elements
• extraction of OSM contributor names needs to be optimized as this takes far to long
• code cleanup and spelling mistakes on the output
• add support to read listing geodata directly from wikivoyage article and generate annotation listing on the fly

  Can't do this. cc-by-sa-1 data from WT can't be redistributed on a map that has to be cc-by-sa-2 :(

Using osm2svg

If you want to play around with this, then get the latest release here.

Remember, it's not near perfect yet

Getting the OSM data

This is the simple part.

While viewing a map on the OSM website:

1. Export
2. Select OpenStreetMap XML Data as the Format to Export
3. Select SVG under options
4. Click the Export button

You will be prompted to save the data as a file called map.svg

Generating a Wikivoyage map

1. Save the OSM data as map.osm in the same directory as the above mentioned source
2. Open osm2svg.xml in a text editor and
   • Specify the area you want to render. This can be done in one of the following ways
     1. Specify a central location in decimal degrees and the height and width in km to render at that location, <locate centerlat="" centerlon="" width="" height=""/>
     2. Specify a bounding box here with minimum and maximum latitudes and longitudes in decimal degrees, <bounds minlat="" maxlat="" minlon="" maxlon=""/>
   • Change title
   • Make sure the theme is set to wikivoyage
3. Execute: ./xsltrans osm2wtmap.xml > map.svg

You should receive output similar to the following:

    osm2svg version 0.09
    Generating svg map from OSM data file map.osm

     Map definition
        Title: Boston/Back Bay
        Theme: wikivoyage 

     Map extent
        Available in OSM data file
           Latitude: 42.273897 to 42.437487
           Longitude: -71.232202 to -71.029286

        Requested for this map
           Latitude: 42.345 to 42.355
           Longitude: -71.0975 to -71.065
           Area is 2.672 km (1.66 mile) wide, 1.112 km (0.691 mile) high 
           and has a diagonal of 2.896 km (1.8) mile

     Scaling
        Internal annotation scale: 0.134
     Retreiving OSM users names for attribution (this might take a while)
     Adding svg metadata
     Adding svg defs sections
        stylesheets
        patterns
        markers
        symbols
     Pre-generate OSM ways as named paths
     Adding license and attribution information
     Drawing the map
        background
        OSM map data
           processing all rules for OSM layer -5
           processing all rules for OSM layer -4
           processing all rules for OSM layer -3
           processing all rules for OSM layer -2
           processing all rules for OSM layer -1
           processing all rules for OSM layer 0
           processing all rules for OSM layer 1
           processing all rules for OSM layer 2
           processing all rules for OSM layer 3
           processing all rules for OSM layer 4
           processing all rules for OSM layer 5
        decorations
           border
           compass
           scale
              using 100meter/yard
     Adding an annotation box
     Adding a symbol box
    Done


The following wiki markup can be used when uploading this file to Wikivoyage:

{{Imagecredit|credit=[http://www.openstreetmap.org OSM] and Wikivoyage user ~~~ |captureDate=2008-05-06 |location= Boston/Back Bay|source=Generated by osm2svg from OSM data and manually annotated by ~~~|caption=Wikivoyage map for Boston/Back Bay  |description=Wikivoyage map for Boston/Back Bay based on OSM data}}

== Licensing ==
{{cc-by-sa-2.0}}

== Source ==

This is a derivative work based on copyright content from contributors to:
OpenStreetMap 
[http://www.openstreetmap.org http://www.openclipart.org]
Distributed under the Creative Commons Attribution-ShareAlike 2.0 License.

as well as Public Domain content from:
[http://www.openclipart.org http://www.openclipart.org]
[http://www.wikivoyage.orgwikivoyage]

=== Attribution ===
;Creators of the source work include, but are not limited to

;Public Domain Work:
Áki G. Karlsson
Finnish Road Commission
Jean-Victor Balin
Nick Roux
Paul Louis
United States DOT

;Wikivoyage users:
~~~

	
;OopenStreetMap users that are known to have contributed to this map:
[http://wiki.openstreetmap.org/index.php/User:MassGIS Import MassGIS Import]
[http://wiki.openstreetmap.org/index.php/User:crschmidt crschmidt]
***some uri's removed here to satisfy wikivoyage's spam checker
[http://wiki.openstreetmap.org/index.php/User:Thomas Matern Thomas Matern]
[http://wiki.openstreetmap.org/index.php/User:dforsi dforsi]

[[Image:Osm2svg-example1.png|right|300px|svg generated by osm2svg]]

The generated svg will look something like the one on the right, open it in Inkscape [3] and change as required. An example of a generated svg file is available at [[:Image:Osm2svg-example-boston_back_bay.svg]]