Mapping the world and all its data
- By Patrick Marshall
- Aug 02, 2004
When Portugal and Holland were battling each other for domination of the oceans and, more importantly, trade routes across those oceans in the 1500s, anyone caught stealing maps of navigation routes was liable to be put to death.
Although maps are rarely considered state secrets today, they remain valuable tools for visualizing certain kinds of data. And computers have given them an interactivity Ferdinand Magellan never could have dreamed of.
Officials at the U.S. Marshals Service, for example, are using geographic information system software from MapInfo Corp. to track concentrations of prison populations across the nation. Federal Emergency Management Agency officials are developing applications based on MapInfo's tools to give field offices and emergency teams interactive access to geographic data to plan response and recovery efforts.
In similar fashion, Washington, D.C., officials have turned to ESRI's ArcGIS to help them integrate GIS capabilities into all government information systems. The city provides Internet mapping services that allow citizens to locate emergency services, schools and libraries. Projects are also under way to provide information on all licensed businesses in the city.
Ultimately, the system is intended to comprehensively link aerial photographs, images and tabular information with digital representations of street networks, buildings and even sidewalks. One major benefit of the system: Federal and local officials can use it to manage traffic and deploy emergency vehicles by the shortest route.
GIS applications have become big business in the federal government. Agencies are spending more than $5 billion on geotechnology each year, and that figure is rising steadily.
GIS programs are relatively straightforward to use. First, you create a map with different features -- points, lines and regions -- that are coded according to a map coordinate system. Then you use a GIS program to attach data to those coordinates. For example, you might link information about household incomes, gathered from U.S. census data, to coordinates in the form of ZIP codes. Then you can ask the map to display, say, all ZIP codes with residents who have an average household income higher than $100,000.
Higher-end GIS programs can be used for other purposes, such as tracking vehicles and determining the best driving routes for couriers or ambulances. The most sophisticated GIS tools can represent data in 3-D, allowing for complex analyses, such as flood risk.
Federal officials considering adopting a GIS solution face a potentially confusing array of choices. In fact, there are more than half a dozen comprehensive GIS applications on the market and literally dozens of niche products. Some high-end programs -- including Intergraph's GeoMedia and Autodesk Inc.'s Autodesk Map -- are designed more for developing GIS applications than for meeting end user's needs. Even among programs designed for end users, the offerings range from ESRI's robust -- and relatively expensive -- ArcGIS family of products to shareware programs that offer relatively modest and/or narrow map-creation and data-manipulation tools.
In this update, we take a look at the two dominant products cited by Federal Computer Week readers in a recent online survey: the ArcGIS family of products, which is in use by more than half of the respondents, and MapInfo Professional, used by about 16 percent of respondents.
Both ArcGIS and MapInfo have undergone significant updates since we last tested them, but their relative market position remains the same. In general, if your agency needs a relatively easy-to-implement, stand-alone GIS solution, choose MapInfo Professional. If, on the other hand, your agency is going to be handling extensive amounts of GIS data in a networked environment, you might be better off with ArcGIS.
In our testing, we focused on a typical agency scenario: Officials deploy the software within a department so that employees in several locations can contribute data to a set of maps. We also evaluated the analytical tools provided to end users and the reporting tools used for putting maps on the Web or printing them.
Finally, we sent the results to a Web server for users to interact with via a Web browser. It is important to note that both ArcGIS and MapInfo -- like many of the GIS solutions on the market -- are capable of much more complex and sophisticated undertakings, including 3-D topographical analysis and real-time routing.
Ultimately, selecting the right GIS solution for your agency will require a detailed needs analysis. And, given the wide array of options, unless your GIS needs are basic, you'll likely want to consider more than just the market leaders.
ArcGIS: All the power you want
ESRI's ArcGIS suite is the Cadillac of GIS: It's big, it's expensive and it has all the power you could want. In fact, ESRI offers so many products and extensions that it can be difficult for new users to keep track of what tools are available with which applications.
Starting at the desktop computer level, ArcGIS offers four distinct products: ArcReader, ArcView, ArcEditor and ArcInfo. ArcReader is, as its name implies, a free viewer for maps produced with any of the three ArcGIS editing programs. ArcView is a solid Microsoft Corp. Windows-based application for editing map shapefiles -- the files that contain actual map shapes -- managing data and performing GIS analysis. ArcEditor includes all the functionality of ArcView and adds more sophisticated shapefile-editing tools. ESRI's flagship product, ArcInfo, has all the functionality of the other products plus more powerful scripting tools, statistical analysis and data-conversion utilities.
We took a hands-on look at ArcView, which is composed of three modules: ArcMap, ArcCatalog and ArcToolbox.
ArcMap is the primary tool to edit and query maps. The program's clean interface hides a wealth of functionality. In fact, a rare problem with ArcMap is that we often had to search extensively for a tool before finding it. And the program's documentation was of limited help.
With a simple map of the United States, we tried to display population density according to ranged fills of color. Such fills of colors or patterns represent a range of values. For instance, in a map showing population, the color blue might represent a state with a population of 15 million to 30 million people.
We searched each of the drop-down menus in vain. We looked up "ranged fills" and "thematic" in the online help, again in vain. Finally, we discovered that right-clicking on the appropriate item in the legend window and selecting Properties opened a dialog box that contained tools for creating ranged fills -- as well as dot-density and proportional symbols -- and also for creating labels and otherwise controlling nearly every aspect of the object.
ArcMap's interface is not intuitive to new users and the documentation could be improved, but once we spent some time exploring the program we found it easy to use.
We were impressed with ArcMap's extensive tools for managing data tables, and we found its editing tools to be powerful and easy to use. In particular, we appreciated ArcMap's ability to edit objects in any map layer without first having to make that layer editable, as is required in MapInfo Professional. Undo and redo operations are unlimited, and ArcMap offers control of map objects, including scaling and rotating objects and defining layer-specific snap settings.
Major enhancements in Version 9.0 include improvements in labeling and annotating maps. The program's new Label Manager and Maplex extensions offer control of label placement and handling. You can easily search for labels by characteristic and apply changes globally, and there is even a dictionary for specifying abbreviations for company names or other objects.
ArcToolbox, which can now be conveniently docked as a window in ArcMap, offers access to tools for advanced geoprocessing tasks, such as address matching and creating buffers or overlays. Don't be put off by the extensive set of tools because you can always collect frequently used tools and keep them in a separate, easy-to-access folder. You'll also find that many of the listed tools aren't accessible unless you've paid for a license to use them. Although the error message that pops up when you attempt to launch such a tool can be irritating, it can also be helpful to know what functions are available at extra cost.
Previous users of ArcGIS will find that the toolbox has been significantly expanded with a host of new utilities, especially in the area of spatial statistics.
We were especially impressed with ArcGIS' new ModelBuilder utility. Formerly available only with the ArcView 3.0 Spatial Analyst, ModelBuilder lets you use drag-and-drop techniques to quickly define geoprocessing workflows that can be used repeatedly.
We also like the fact that ArcGIS geoprocessing tasks can be performed remotely, allowing the burden on CPU time to be evenly distributed.
The third module of ArcView -- ArcCatalog -- allows users to browse and manage data files without having to actually load them into ArcMap. The simple interface makes it easy to create or edit meta data, or to change attributes in files. What's more, if you do want to open a file, you can simply drag and drop it into ArcMap.
ArcGIS' support for enterprise databases and data file formats is unsurpassed.
ESRI also offers choices on the server side. If all you want to do is publish a map on the Internet that is readable and has basic query capabilities, you'll want to use ArcIMS.
Publishing a Web-based map involves several steps. First, you create a new map "service" using the ArcIMS Manager, then add the various map and data files. You can also specify layer properties, such as symbols that will be employed and the order in which layers will be drawn.
After selecting a map service and specifying the data that will be included, you choose a viewer and select interface elements. ArcIMS lets you specify either an HTML or a Java viewer.
We were impressed with ArcIMS' performance and scalability. The program offers good tools for tracking the number of users and response times of the map servers. If performance drags, you can increase the "instances" of virtual servers running and/or you can install ArcIMS Spatial Server on another computer and enable load balancing.
If you need even more power in publishing map applications, you should consider moving up to ArcGIS Server, which is
a comprehensive toolkit for enterprise and Web application development.
Finally, the ArcGIS suite earns high marks for overall programmability. Unlike most other GIS solutions, ArcGIS has an open architecture composed of more than 1,100 components that can be employed using the built-in Microsoft Visual Basic for Applications scripting or programming languages such as Visual Basic or Visual C++, in addition to the ArcGIS Server environment. With Version 9.0, ESRI officials have introduced ArcGIS Engine, a collection of embeddable GIS components that can be deployed to third-party applications, such as Microsoft Word.
The bottom line
There's no getting around the fact that a decision to adopt ArcGIS will involve a significant amount of training time, especially for those responsible for map creation and application development. But we have found the tool to be easier to use than other enterprise-level solutions.
In short, if you can't find a way to accomplish your GIS chore with some combination of ArcGIS tools, it probably can't be done. As ESRI continues to make ArcGIS more powerful, the suite's ease of use is also improving considerably.
MapInfo sports new functionality
Designed as a Windows application targeted at end users, MapInfo Professional has always been among the easiest GIS programs to use. With each new version, however, the company continues to add tools and platform support aimed at eating into the enterprise market share owned by companies such as ESRI, Intergraph and Autodesk.
In our review of MapInfo 6.5 in 2002, we were impressed by its advanced editing features, including its ability to generate gradient shading, its polyline smoothing tools and its ability to easily create polygons around map objects. Other features included translucence settings for layers, a capability we still haven't seen matched in other GIS programs.
We were also impressed with MapInfo's introduction of snap tolerances and its new ability to separate objects.
Since Version 6.5, the company has significantly added to the tool's functionality.
Among the most interesting new features in Version 7.5 of MapInfo is the addition of Vertical Mapper, a raster-based tool for performing spatial queries on grid layers. The tool supports 3-D viewing and analysis, data aggregation tools, grid contouring and other grid-based operations. Unfortunately, Vertical Mapper is only partly integrated into MapInfo. It can be used to open, view and print grid files, but editing capabilities are not yet integrated.
Version 7.5 also adds a new, easier-to-use interface for registering raster images and supports more than 20 raster file formats.
MapInfo's capabilities for creating map objects have been enhanced with dozens of new features and tools. The rotation tool, for example, allows you to rotate map objects and labels. And the tool enables you to specify anchor points and fixed angles, and it offers more control over its already robust fill-pattern tools. In addition to providing an additional 100 fill patterns, pattern resolution has been increased to 32 x 32 pixels.
New tools include a cogoline tool, which draws a line of a specified length and angle, and a polyline split tool.
Also welcome is MapInfo's more generous, though still limited, undo capability. The undo buffer of the program has been expanded to 10M, enough to provide for the needs of many, and perhaps even most, users.
MapInfo's map object capacity has also grown, increasing from a practical limitation of around 32,000 nodes for a single region or polyline to more than 1 million nodes. That gives MapInfo the ability to handle large and complex maps that previously only products such as ArcGIS could manage.
At the same time, it is worth noting that MapInfo does not support remote processing and load balancing to improve performance during map creation as ArcGIS does.
However, we continue to be impressed with MapInfo's broad support for projections and external databases -- including, most recently, support for Oracle Corp.'s Spatial 9i, MapInfo's SpatialWare 4.6, Microsoft's SQL Server 7.0 and 2000, and IBM Corp.'s Informix -- and by the speed with which the company provides support for new versions of major databases.
MapInfo is unusual in that it performs all of its data operations "inside" the external database. The main advantage of this strategy is that synchronizing data is never an issue. However, with large operations, network bottlenecks can occur.
We were impressed with MapInfo's new Workspace Packager, a tool that allows users to save a copy of their current work space, including all referenced data. Using this tool, you can quickly access data even if you've moved the work space to another computer. Just as important, you can send complete work spaces to other users.
On the Web
When we last looked at MapInfo's solution for publishing maps to the Web, we tested MapXtreme, which is essentially an application development program. If you were publishing any but the simplest projects, you had to roll up your sleeves and start programming.
Although MapXtreme is still available for developers, MapInfo has introduced MapInfo Discovery, a tool for quickly and easily publishing map projects to the Web.
After installing Discovery on your Web server -- a process that involves setting up both an FTP server and a Microsoft SQL Server database -- and local MapInfo workstations, publishing a map to the Web is relatively simple. At the desktop PC level, you simply choose the Map menu and then click on Send Map To/MapInfo Discovery Server. Users will need to know the Discovery server name set up by the administrator.
At this point, the publisher can specify public access or require a password.
Finally, you need to specify layers to be included in the Web map. MapInfo files can be referenced, if they already reside on the server, or you can copy local map files to the server.
Once maps have been published to the server, they are managed via the Discovery server administrator program, a straightforward Windows-based utility that resides on the Web server.
There are a few wrinkles in the way maps display on the Web. For starters, thematic maps -- in which regions are shaded or colored based on a value -- cannot be displayed, with the exception of grid maps. This is a significant limitation. Also, colors weren't quite what we expected in some cases, and custom labels did not appear. On the whole, however, we were impressed with the ease of publishing maps with basic interactive functions.
One drawback of MapInfo Discovery as a Web solution is that it requires your Web server to employ Microsoft's Internet Information Server and SQL Server. If you don't have SQL Server installed, Discovery will install it.
The bottom line
MapInfo doesn't match ArcGIS when it comes to scalability and network muscle, nor does it offer some of the higher-end geoprocessing tools that can be added to the ArcGIS suite.
However, MapInfo remains the front-runner of the desktop GIS applications, offering a surprisingly strong set of map creation and querying tools in an easy-to-use package. Just as important, MapInfo is backed up by an extensive network of consultants who are ready to provide custom applications. Federal officials considering doing their own in-house application development, however, should note that MapInfo development requires the use of MapInfo's proprietary programming languages.