In the summer of 2001, the geographic department of the city of Apeldoorn (pop. 154,000) in The Netherlands sought a better way to produce small-scale maps. Up until that point, 1:10.000 and higher scale compilations (internally referred to as 'roadmaps') were produced in Bentley
Microstation but their cartographic quality was poor, added to which much production was undertaken on an ad-hoc basis and there was little idea as to which maps were available, let alone their age or accuracy. Often, multiple versions of the same map were in use.
In the previous year, eXQte, the Dutch reseller for Avenza MAPublisher software (a cartographic plug-in for Adobe Illustrator/Macromedia Freehand), and the FME suite from Safe Software (a package for converting and processing GIS data), had delivered these products to Apeldoorn, but the drive to get them up-and-running was absent, due largely to unfamiliarity with the software and lack of time to redress the problem. For this reason, a consultancy project was initiated to help Apeldoorn change the way its small-scale municipal maps were produced.
What should it contain?
An initial requirement was that the new map production process should use as much existing data as possible and thereby limit the datasets being maintained to a minimum. The first step was thus to make an inventory of Apeldoorn's available data products. It was agreed that in order to produce a successful city map, there was a need for a (classified) road network made up of centerlines, streetnames,land-use areas, thematic information such as the contours of important buildings and point symbols indicating various important features. Much work was devoted to updating and perfecting the initial set of source files. e.g., all road centerlines had to be digitised as these were not previously available.
Another expectation was that the process should be repeatable and further effort was expended developing and automating the process so that a new version of a map could emulate the same style as its predecessor ... and be produced with speed.
To enable this process, a set of FME scripts was defined that prepared the data for further use in MAPublisher (running on Adobe Illustrator). As the version of MAPublisher then being used didn't support Microstation DGN, it was decided to use FME to convert all the DGN data to MapInfo mid/mif. At the same time, selections and clips were made in FME. These clips were necessary as the map files covered the entire municipality, the city itself representing just a small part. The intended output was an AØ-size 1:12.500 scale city map. The final FME process is controlled via a batch file.
How should it look?
With the basic process defined, a lengthy phase ensued to decide on the look of the output. Not only had it to be produced quickly, it also had to compare favourably with commercial mapping.
At one point, it was decided to superimpose aerial photography on the map (the vector data being displayed transparently) to break up large areas of single color. For example, a sizeable forest west of the city would otherwise be shown as a huge green area. Adding the photography would provide some texture and make it more visually attractive. The style of the map was defined in a standard MAPublisher legend.
How should it be used?
When finally defined, the process consisted of several components for use in the following order:
1. A set of FME scripts (aka mapping files) that make a clip of the desired area and prepare the data for use in MAPublisher. The coordinates of the desired area are specified through a batch-file by the operator. These scripts output a set of mid/mif files.
2. The mid/mif files are imported into MAPublisher and set to the desired scale. The order of the layers (one mid/mif file equals one Illustrator layer) is vitally important and needs to be checked.
3. The standard MAPublisher legend is processed to set the style of the map.
4. A georeferenced tiff file with the aerial photo (clipped out of a MrSid file using the MrSid Viewer) is placed and registered by MAPublisher.
5. Texts (the only component maintained in Illustrator) are placed. The cartographic placement is done only once for the entire municipality. All the maps being produced simply use a clip from this file.
6. A PDF is created of the finished map image. This PDF is then placed in a standard document with all peripheral information such as title, legend and (in case of the standard streetmap) an index of the texts.
From this final document, a second PDF is created which is stored on a central server and printed on request. Using this process, it is now possible to create a new, standard map of the city in approximately 20 minutes. Thanks to the MAPublisher legend and the FME scripts, maps can be produced without any subsequent manual editing.
Moving on
In mid-2002, the municipality embarked on a move to centralise its geodata holdings in the geographic department. This meant that the department would assume responsibility for thematic map production and, accordingly, a derivative of the standard road map was produced as the standard base map for this purpose.
Thanks to this base map, available for two areas and in three paper sizes, thematic map production has been totally revamped. By generating them in Illustrator/ MAPublisher, cartographic quality was improved and style was maintained to a common consistency. Indeed, the department’s reputation is now such that it is now engaged in mapping projects for all kinds of clients.
Looking to the future, the basic A0 map will be updated twice a year and any ad-hoc maps produced will always use the most up-to- date set of source data. And with style and content maintained to a consistently high standard, the City of Apeldoorn is guaranteed a high level of cartographic quality for its future map output.
Hans van der Maarel is a GIS engineer with eXQte in Klundert, The Netherlands, and can be contacted by email at: hans@exqte.nl
More Information
Adobe: www.adobe.com
Apeldoorn City Council: www.apeldoorn.nl
Avenza: www.avenza.com & www.mapublisher.nl
eXQte: www.exqte.nl
Safe Software: www.safe.com