Information Technology Reference
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The primary publication medium for this system has been paper prints. The city has now decided to
publish the maps in both paper and PDF, with PDF the actual main format, used to print to paper as needed.
However, producing quality PDF maps has turned out to be a little more complex than simply selecting the
Export to PDF option from the Export menu.
The city chose to use the ESRI DS Mapbook extension, which allows them to create a single multi-page
PDF which contains all 286 tiles of the city. Each tile is 500 meters by 800 meters, a size that exactly fills
an 11 × 17 page at a scale of 1:2000. While the resulting multi-page PDF is large at about 150 MB, the
individual maps are quick to find and display. The single file approach makes it very easy to distribute the
entire set, since it only requires the copying of one file.
Goals
Obtaining a compact, quality image that would print reliably on an industry standard 11×17 laser printer
was a major goal of the effort. To insure compactness, a dpi of 300 was chosen. It was also decided to use
the Universal Condensed font set, which could be closely matched by Adobe's font substitution routines so
that the fonts would not have to be embedded. This helped reduce file size, as well as insuring that the
PDFs would print consistently, regardless of the printer hardware. Wherever possible, the standard ESRI
symbol sets were used to insure consistency and minimal file size.
This product is now being delivered, and the city is looking for ways to improve it. Among techniques
being considered are thematic layering, the addition of navigational hyperlinks and the inclusion of feature
data attributes. Like many municipalities, the city of Burnaby has just begun to tap the abilities of PDF for
distributing their GIS data to the non-technical consumer.
Case Study Two: An Intelligent Map System
North Georgia EMC (NGEMC), an electrical supplier to 95,000 customers in North West Georgia, has
implemented a complex map viewing system based on Layton Graphic's GeoPDF technology. NGEMC
utilizes a customized AutoCAD system to create and maintain over 1,100 individual maps of their coverage
area, using the Georgia West State Plane coordinate system.
Each map contains feature data about the facilities represented on the map in the form of blocks with
attribute data. The data contain customer location, transformers, fuses, poles, switches, reclosures, line
sections and substations. In addition, there is a separate Customer Information database with information
about each current customer.
Converting and Geo-registering the Files
In order to make these data accessible to field and engineering personnel, NGEMC converts each DWG file
to PDF, using customized DWG-to-PDF software provided by Layton Graphics. Each DWG is rendered to
PDF with only the necessary layers displayed and with a set of custom colors to make the data more
readable in Adobe Reader, which uses a white background rather than the standard AutoCAD black
background. All title block data, reflecting the map name, the map's position within the overall map grid
and revision data are retained (Figure 14.4).
As each PDF is rendered, a post-processing program searches a database for the coordinate points of the
corners of the map neatlines and automatically geo-registers the PDF. The processor then searches the
associated DWG to determine the state plane coordinates and attributes of each block in the file. The state
plane coordinates are transformed to PDF coordinates and the data placed at those points as a custom
Adobe annotation. As a user cursors over an annotation, they are alerted to its presence. A single click
displays the annotation.
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