INDEA Map Production

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, and
• 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, and
• 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.