Cadalyst Labs Review: Autodesk Map 3D 20071 Sep, 2006 By: James L. Sipes
Full range of geospatial data tools complements CAD
Integrating CAD drawings and GIS data has been amazingly frustrating. That situation is changing, though, as CAD programs get better at working with geospatial data and GIS programs provide better drawing, editing and CAD file import tools. One program that seeks to bring together the CAD and GIS worlds is Autodesk Map 3D 2007. With this latest release, Autodesk makes it clear that it's serious about integrating geospatial data into CAD.
Evolution of Map 3D
Map 3D was introduced in the mid-1990s and has evolved considerably over the past decade. I hate to admit this, but when I used some of the earlier versions of Map 3D, I came away thinking that Autodesk just didn't get it. It seemed that Autodesk was taking a CAD approach to geospatial data, and the result felt more like a CAD add-on than a full-featured set of geospatial tools.
Autodesk Map 3D 2007
The strength of Map 3D 2007 is that it builds on the capabilities of AutoCAD and then incorporates a full range of tools for working with geospatial data (figure 1). This version of Map 3D is built on the latest release of AutoCAD software, so there are no compatibility issues.
Figure 1. New data management tools in Autodesk Map 3D 2007 make it easy to effectively manage spatial data. Here, the Schema Editor quickly defines schemas.
One of the most promising features of Map 3D 2007 is multiuser editing (figure 2). Users can access a collection of drawing files called a drawing set and make modifications to any of the drawings simultaneously. With a file-based system such as AutoCAD, only one user at a time can edit a drawing.
Figure 2. One of Map 3D 2007 s strengths is multiuser editing capabilities, especially multiuser editing of DWG files. Using the software s query functionality, multiple users can access and edit the same sets of files or base maps simultaneously.
It's much simpler to create thematic maps in Map 2007 than in previous versions. The Display Manager can be used to create styles that define the layout of a map, and new styling tools simplify the process of creating maps.
Speed and Performance
One of the first things I noticed about Map 3D 2007 is that it loads much faster than previous versions. Sitting and waiting for the software to run through its startup routine used to drive me nuts. Autodesk has touted the increased speed and performance of Map 3D 2007, and for the most part the company has delivered. This capability is critical because GIS data sets are significantly larger than CAD drawing files.
One complaint about previous versions of Map 3D is that it could be sluggish when accessing large data sets. This version of Map 3D includes a new high-performance engine and is much more adept at handling large data files, including DEMs (digital elevation models), DTED (digital terrain elevation data) and ESRI GRID files. I'm working on one project that includes a dataset of almost 2GB. It still takes longer than I'd like to load the file, but it's much faster than in previous versions. After the file is loaded, the tools for creating, modifying and viewing are very responsive.
As with most graphics-intensive programs, the more RAM and disk storage space, the better. I noticed a significant difference in performance when I switched to another computer that had double the RAM of the first. Working with large geospatial data sets can be very frustrating if the software you are using is sluggish and unresponsive.
One of my favorite Map 3D tools is the versioning feature (figure 3). It allows you to store more than one scenario in the database. As a designer and planner, I'm always exploring options and developing different alternatives. It's nice to be able to save each alternative as a different version in the same database, rather than creating four or five different files. Versioning allows me to quickly compare even the most subtle differences between alternatives.
Figure 3. Using the database versioning features of Autodesk Map 3D 2007, designers and analysts can create and store more than one scenario in a database.
Reading and Editing SHP Files
Autodesk advocates an open, flexible environment that makes it easier to work with different data formats. This version of Map 3D is able to read and edit a wide range of CAD and GIS file formats. I was impressed with how well Map 3D 2007 reads ESRI SHP files, one of the fundamental GIS formats. It's nice to simply drag and drop SHP files and add them to a drawing without having to translate the data from one format to another. No translation is involved—Map 3D 2007 allows you to edit geospatial data in its native format. Regardless of how good translation programs are, they always have the potential for error. Direct access means no data translations, which in turn ensures data accuracy.
Anyone who has tried to modify data using GIS editing tools knows how frustrating it can be. Every time I do, I bemoan the fact that I don't have trims, extends, fillets and the other commands that CAD users take for granted. Fortunately, most GIS users haven't spent any time with CAD programs, so they don't realize how much easier it is to edit line drawings in a program such as AutoCAD.
Editing in Map 3D 2007 is pretty straightforward. You select Check-Out from the Edit menu and then select the feature you want to edit. You can make any edits you need. After you finish, checking the feature back in saves your changes and makes them available to other users. If the Update Edits Automatically function is turned on, all of your edits also will be written back to the data store as you make your edits.
Because Map 3D is built on AutoCAD, you can use all of the normal editing tools. Even if Map 3D had no other features, just simply being able to draw and edit lines, arcs, polylines and polygons in a georeferenced world could well be worth the cost of the software.
Coordinates and Projections
In the CAD world, geospatial data has always been an afterthought. One of my biggest frustrations is trying to import CAD data into GIS, because most CAD users don't set up their drawings using coordinate and projection systems. Many CAD users I know don't know much about projections, coordinate systems or metadata, and they don't see a need to learn.
Map 3D supports geographic projections, coordinate systems and datum that CAD programs typically don't. According to Autodesk, Map 3D supports more than 3,000 coordinate systems. This means that there's no reason for CAD drawings to not connect with the real world. I hope the days of using 0, 0, 0 as the origin for drawings is coming to an end.
There are fundamental philosophical differences in how CAD and GIS programs work. GIS applications typically access external databases that are used by multiple users, while CAD uses are focused on a single drawing file. As a result, CAD users often lack the experience in working with databases that GIS users have. Fortunately, the new data management tools in Autodesk Map 3D 2007 simplify the process of managing spatial data.
This version of Map 3D introduces a new file format called SDF (spatial database format). SDF is a file-based personal geodatabase that can store spatial and attribute data for multiple feature classes (figure 4).
Figure 4. SDF is a powerful single file that provides many of the capabilities of a relational database. Users can organize and manage their data as GIS features, providing a solid foundation for a smooth transition to a relational database in the future.
SDF provides many of the capabilities of a relational database and helps organize and manage geospatial data. In the world of GIS, personal geodata-bases are becoming commonplace, and I expect that soon almost every project will be built around one. The SDF format is easier to create and manage than most database systems, and all of the data for a project can be stored in the same SDF file. Because all of the drawing information is linked, it's possible to conduct a query that filters through even the largest datasets. I was impressed by how quickly queries were completed.
In Map 3D 2007, Autodesk also enhances FDO (feature data objects) providers. Oracle and ArcSDE were introduced in the previous version of the software. This release now also supports Microsoft SQLServer, MySQL and ODBC databases and Web map and feature services.
Like AutoCAD, Map 3D is a vector-based program. Raster images are used primarily as background information that can be georeferenced. This design is a potential limitation because many of the analytical tools in GIS programs are raster based. Map 3D still lacks some of the analytical tools found in high-end GIS programs. It provides geospatial analysis tools such as network tracing, buffering, thematic mapping and polygon overlays, and this type of analysis will probably meet the needs of most CAD users.
One option is to add a program such as Autodesk's Raster Design to your bag of tools. Raster Design provides raster analysis and manipulation tools such as color mapping, multispectral analysis and rubber-sheeting. Land Desktop, Civil 3D, Survey and Utility Design are other Autodesk programs that can be used in conjunction with Map 3D. The only downside to this approach is that it increases the cost of your tool set.
Recommended system requirements for Map 3D 2007 are an Intel Pentium 4 with 512MB RAM and 1.5GB free disk space running Windows XP/2000 (SP4). Installation is blocked on Windows 2000 (SP1 and 2)/NT/9x. You'll also need a 1024x768 video display with true color, a mouse or other pointing device, and a CD-ROM drive.
Bridge from CAD to GIS
Autodesk promotes Map 3D to GIS managers, GIS specialists, mapping technicians, planners, and facilities and infrastructure designers and managers. It seems to me, though, that it's geared primarily for CAD users making the leap to integrating GIS. Most GIS managers I know were weaned on ESRI products, know very little about CAD programs, and typically aren't inclined to change their approach to projects. But for both CAD and GIS users, Map 3D 2007 has a lot to offer. Highly Recommended.
James L. Sipes is a senior associate with EDAW in Atlanta, Georgia, and the founding principal of Sand County Studios in Seattle, Washington. Reach him at email@example.com.