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Several different types of EBC map series can be produced from the
INDEA, using special-purpose software written by BCS, which runs in
combination with the automated labeling package Label-EZ (from MapText,
Inc.) and the GIS package ArcView (from ESRI). The most complex
category of maps, by far, is the Voter Area (VA) map series, as it
involves a large number of maps, each of which may contain several
insets. The production of these VA maps is described here; the
procedures for other map series are similar but simpler, and do not
involve the complicated inset generation and management stage.

Example Voter Area Map (pdf)
There are five distinct phases to the process of VA Map creation:
- initialization
- inset management
- new map generation
- labeling
- layout and printing
Each of these is discussed in a separate section below.
Initialization
Initialization involves bringing INDEA data into the map production
system, and setting up this system appropriately. As with the INDEA
Data Manager, the linework and attribute data can be imported either by
extracting data directly from the INDEA, or by loading the contents of
ESRI shapefiles.
Production of the VA maps for each separate Electoral District (ED)
requires setting up a new project in ArcView. This INDEA data is then
loaded into a main “root” directory, specific to each ED. The files are
then run through an initial batch process to set up information for the
density displays and the necessary information for the labeling phase.
Inset Management
An inset is a map that has been generated from
some or all of another map. Insets are defined interactively by
facilities provided in the ArcView-based map production environment
developed by BCS. They are specified manually, by adding and moving
points to form a polygon defining the inset region. This inset can then
be scaled and placed in one of three ways: on the same map, on a new
full-size map, or on another map containing only other insets. The
corresponding region where the inset will be placed is called the outset polygon.
If an inset will result in a new full-size map, then its shape and
size are predetermined. For the other cases, the size and position of
the new map information must be specified. Extensive facilities are
provided for specifying the shape, scaling and placement of insets. For
this purpose, a hierarchy of directories is automatically created and
maintained by the inset management software.
A particularly useful tool for inset management is the density
analysis utility. This tool finds and highlights all street segments
that do not meet a density criterion. This criterion, which is related
to the scaling required for the segment to be labeled, is determined
automatically and depends on both the length of, and free space around,
each street segment. This analysis acts as a visual guide for possible
scaling and inset placement. The suggested scale and placement may be
adjusted manually, using the density analysis tool to indicate an
appropriate scaling.
New Map Generation
Following the inset generation and placement stage, the map
production system can then be used to transform into new maps the data
that was set up in that stage. Briefly, this automated processing
involves the following tasks:
- A new theme is created that contains polygons from the original graphics
- New directories (descendants of the directory housing the data from the current view) are created
- All the data enclosed in each of the insets is clipped and written to files in the appropriate directory
- Files for controlling labeling are created and also sent to the same directory
- New views are created for each of the maps
- Casings are applied to streets if the scale is less than 1:5500
- The areas from which the insets were taken in the original maps are thinned
Labeling
The automated labeling package Label-EZ is used to label the
features on the maps. In BCS's map production environment, this package
runs in association with ArcView, with input and output in the form of
shapefiles. Label-EZ provides a powerful and flexible environment for
labeling all types of map features, and, if a reasonable scale is
chosen, consistently achieves a very high degree of success (i.e.,
essentially all streets are labeled , either directly or with leader
lines). Some of its capabilities include:
- various options for labeling streets, including curved labels
- automated leadering
- feature suppression
- collision avoidance
- prevention of labeling through intersections
- labeling at regular intervals
- avoidance of mislabeling for nested polygons
- alignment at beginning, middle or end of segment
- display of attributes such as street numbers
One of the steps in the processing described in the above sections
is the production of control files for input to Label-EZ, as well as
the map data itself. Thus, when the new map generation phase is
complete, the stage is set for running Label-EZ. This is done as a
separate invocation, outside the ArcView inset management and new map
generation environments.
Layout and Printing
Each layout represents the final printed map. The entire set of
layouts is generated when the appropriate option is selected. Once the
layouts are generated, each contains the maps and insets as they will
appear in the printed output. Each will also have a legend bar
that is specific to EBC. Although the maps and insets themselves cannot
be edited in the layout, they can, however, be altered in the View, and
then transferred to the layout, by setting a live link to capture the
updated map.
Several objects are automatically generated and placed in a layout;
they can also be edited using the regular ArcView methods. These
objects include:
- inset neat line
- north arrow
- inset name labels
- scale bars
- map identifiers
Each layout can be printed individually, with the page size set to
the paper size. Printing is done by simply using ArcView's Print Setup
and Print items in the File menu.
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