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User:Al guy/maps

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This page contains material on making maps for Wikipedia. See my user page for examples of some of the maps I've made. Contact me if you have further ideas, questions, or comments.

Data

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Maps generally require good source material. I generally use GIS data and have listed some sources below. The Wikipedia:Map page contains some non-GIS sources such as blank png sources.

GIS data is vector data containing info about its relation to real life (lattitude, longtitude, size, elevation, etc.). This type of data can not be used directly with most graphics programs. I use the ESRI .shp file format for my projects and all the following sources provide data in that format or the data can easily be converted into that format.

North America:

  • Bureau of Transportation Statistic contains politcal boundaries (state/province), road and rail data for Canada, US and Mexico. (public domain)
    • a conversion tool available from their website can be used to convert the data to ESRI .shp format

Canada:

  • GeoGratis detailed provincial and national data. (available under suitable license)
    • provided in .shp format

Software

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I have used two free software packages to manipulate the GIS data. Both allow you to import 'themes', such as political boundaries, roads, rail, water, etc. I have found that fGIS has more powerful query features (allows you to only display 'CP' track) and can reproject your data (from geographic -> Mercator).

  • ESRI ArcExplorer - the free viewer from ESRI which also sells full GIS manipulation software.
  • fGIS - from the University of Wisconsin. I recently started using this software and am finding it in some ways superior to ArcExplorer]

For graphics software, I use GIMP.

Making Maps

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Generally, my procedure is to import the data into the GIS software, identify which data I want to display, resize and zoom to display just the data I want to show in my map, export each theme to a separate layer in GIMP (via clipboard or by saving to files), then colourize and label in GIMP.

  1. Importing: only import the data you think you might use since some data sets are huge (50+ MB).
  2. Displaying in GIS: don't worry about picking colours in the GIS software because it is generally easier to manipulate the colours in GIMP.
  3. Sizing: I have found that deciding on the size of your map using the GIS software works best. Resizing in GIMP usually causes details to disappear - the GIS software will display a road as a 1pixel line regardless of the zoom factor but if you resize in GIMP, the 1pixel line might disappear.
  4. Layers: In GIMP, put each theme (rail, political, water) on separate layers. Make upper layers transparent by 'selecting by color', selecting the background colour of the upper layer, and selecting 'clear'.
  5. Colours: I try to use the colours from the Wikipedia_talk:WikiProject_Maps.
  6. GIMP tricks: to emphasize 1 pixel roads/rail, select the road ('select by color' or 'by continuous') then 'enlarge' by 1 pixel, then fill with your preferred colour.