Keywords: Atlas for Schools, Multimedia Cartography
Tobias Dahinden (b. 1973) studied geodesy. Currently he's a PHD student at the Institute of Cartography of the Swiss Federal Institute of Technology. He is working with SVG since spring 2000. He was part of the organization committee of the 1st SVGopen conference. He coaches students in works concerning SVG. Since 2004 he's main-developer of the IKA-SVG-Viewer (an open source SVG-Viewer based on PersonalJava).
Kathrin Kellenberger is master science student and member of the swiss national snowboard team.
Isabella Flüeler is master science student.
During the last years the wish growed up to add an interactive part to the swiss atlas of the world. That's why we started a project in summer 2003 to evaluate how to produce interactive maps for the atlas.
The first part of the project was about the conversion of existing maps. In a second part we inserted additional multimedia elements in a map. In a third part we ask some teachers what they think about our work. A forth part was about a database driven map production.
Conversion of existing maps to SVG
Conversion of the FreeHand-File
Conversion of the DGN-File
Graphical quality of the maps
Is an interactive map "better" than a printed map?
Database driven map production
The swiss atlas of the world for secodary schools exists since 1910. It was renewed periodically about three times per decade. The atlas consists of about 400 maps of different topics and of different towns, regions, countries and continents. The data shown in the maps are stored on papers, to each map belongs a box with several hundred papers. Since 2002 each map is also stored in DGN- or in the proprietary FreeHand9-Format. The atlas is released in book form in three different languages.
The topics of the maps in the atlas are rather different. Yet there are maps about geography and economy from all over the world. But the scale of the maps are not equal around the world. Economy and geography from Europe is in scale 1:4 Mio., Southern America in 1:25 Mio., Asia in 1:15 Mio., Africa 1:30 Mio. There are some maps about clima of Europe in 1:15 Mio. Further there are a lot of very special maps like "City of Paris", "Donana National Parc" or "Colonisation of Saskatchewan (Canada)"
Teachers often told the producers that maps in the atlas were to difficult for students to understand. That's why in 1996 the idea grew to add an interactive part to the book.
The producers asked the theacher what kind of interaction they would like to use. The result is an never ending list of whishes [SWA, 2003] . The whises concern interaction like 'switching layers on and off', 'fly throu the area', 'access maps with a database of names', 'select exonyms by a database and create a new map',...
In summer 2003 the idea of a interactive, digital part of the atlas became more precise. Because there is no similar atlas-project with a digital part, we decided to make some preliminary research for developing such an atlas.
As a first step we tried to convert two existing maps in SVG. The interactive map should have the possibility to zoom and to switch layers on and off.
The first map is an economy map of California, print-scale 1:4 Mio. It's size is about 13,5cm x 8,5cm. The file was stored in FreeHand 8.
The second map is an overview-map of New Zealand. It's scale is 1:15 Mio. and it's size is about 12cm x 11cm. The file was stored in Intergraphs DGN-Format.
Both map had not a detailed legend. We drew this legend and added it to the graphic. We also added some basic interaction to the graphic.
We had two reason why we wanted to convert the maps to SVG. The first was the experience we already had with SVG. The second is based on the article of [Räber, 2001] where you can see some advantages of SVG for map production. The article gives also some hints for the production of a digital map with high quality.
The conversion of a FreeHand file in SVG is rather straight forward. Import the File in Adobe Illustrator (Version 9 or higher) and than save the file as SVG as proposed by [Schnabel, 2003] . Yet we had some problems:
The SVG source has to be cleaned. After that we included four kind of interaction. The first is an extra option for zooming and panning the main part of the map. The second is a possibility to switch layers on and off. A third shows some additional informations for cities in a separate text area. The forth highlights a part of the legend when the mouse is over a symbol.
The SVG was included in HTML-Frames. This is not important. We did this for test purposes. We made a kind of mini user interface in HTML. It is also possible to scroll the whole graphic now if it's larger than the screen. A screenshot of the result shows Figure 1 .
Figure 1: California
The picture shows a screenshot of the map of California of [SWA, 2004] .
The conversion of DGN to SVG can be made with several different programs. We tested some direct converter like "dgn2svg", and conversions via GIS-Software (Import of DGN in ArcMap). The most usable way was an import in Adobe Illustrator by Avenza's MaPublisher. After that import, we used SVG export of Illustrator. We cleaned the SVG code included interactions, and embedded the SVG in a HTML-Frame. See Figure 2 .
The interactions we used are:
Figure 2: New Zealand
The picture shows a screenshot of the map of New Zealand of [SWA, 2004] .
The map files we have are optimized for printing. In the preceding work we showed that a conversion to SVG is possible. Now we wanted to add some mulitmedia stuff to a map. Here we have to say that the term "multimedia map" is not defined exact. We just added some additional texts, pictures, movies and sound to a map.
The map we worked with is a graphic of the landuse of Iceland. Its original size is 13,5cm x 8,5 cm, the scale is about 1:4 Mio.
The additional informations, picutres, national anthem and movies were taken from the world wide web. A commercial release would need data where the copyright belongs to the Atlas producers.
Figure 3: Island
The picture shows a screenshot of the map of Island of [SWA, 2004] .
As you may see in Figure 3 we added four extra symbols for the multimedia elements. There is no detail legend in the map. But we show the explanation of a symbol on mouse-over in an extra square. Layers were merged in 8 groups.
An unexpected problem were the special characters of certain names of iceland. In the original file the character were stored as path. This is fine for printing but not for digital maps. Because of this we have no mouse-over effect with fonts.
The interactive map of Iceland, California and New Zealand were shown to 10 teachers of geography. We asked them if the quality is high enough and if the interaction is useful. We also wanted to know, if they would use such maps in their lessens and if they like the multimedia elements.
Most teacher said that additional multimedia is nice to have but not important. In our version it was not clear enough which information is behind the multimedia buttons. But multimedia may help teachers to prepair the lessons and make them more interesting. The use of sound is not common, it could be used as an example for special languages.
We asked the teachers five question. They were allowed to say yes or no. Nearly every question was everytime answered with yes:
All interactive maps are available on [SWA, 2004] .
Yet it would be nice if symbols are not resized by the factor the view is scaled.
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