Spatial Technologies-Illustrating Geospatial Information31 Oct, 2006 By: James L. Sipes
Graphic illustration software lets you create high-quality maps.
In the world of computer graphics, integration is key. CAD programs are incorporating analytical tools, GIS programs are adding drawing tools, and the line between illustration and image-processing programs is getting blurry. The reason for this focus on integration is that users realize that regardless of what programs they are using, other tools out there may be beneficial for what they are doing.
GIS professionals are interested in producing high-quality maps. When the tools in GIS programs aren't up to the task, they look for other programs that can help, including illustration programs. Illustration programs typically are vector-based, in large part because vector graphics can be printed at even the highest resolution without a loss of quality. Vector illustrations also can be edited easily by simply moving points, adjusting curves, moving edges and changing colors or patterns.
In this Article
Tools of the Trade
Adobe Illustrator, Adobe (formerly Macromedia) Freehand and CorelDRAW are among the most popular illustration programs. Illustrator CS2 is the latest offering from Adobe—it provides the tools to create graphics for a wide variety of uses, including print, video and the Internet. With CS2, you can easily move files back and forth between Photoshop and Illustrator. Illustrator artwork can be brought into InDesign, a graphics layout tool, and then edited using InDesign tools. Even transparent artwork created in Illustrator can be used in InDesign.
Freehand is used for design, editing, storyboard development and document production. I really like its ability to apply unlimited stroke, fill and effect attributes to an object. Its drag-and-drop features help simplify the process of creating Web pages. I used to work with a graphic design firm in Seattle, and it preferred Freehand to any other illustration program because it was better at handling large, complex illustrations.
ACD Systems' Canvas 9 Professional Edition is intended primarily for technical illustrators who need to produce precise, high-quality images. Canvas X is more of a drawing tool than an illustration tool. It has many of the same kinds of tools you'd expect to find in a CAD program and brings a very high level of precision. For example, Canvas has tools to create dimension plans that show the real-world size of objects on your drawings. You find these kinds of tools in CAD programs, not illustration or GIS programs.
Xara X is illustration and drawing software also used to generate Web graphics. Inkscape is an open-source vector graphics editor with capabilities similar those of Illustrator and Freehand. Sodipodi is a vector-based illustration-drawing program distributed under the terms of the Gnu general-public license. Zoner Draw 5 is a graphics editor with a set of tools for developing illustrations, maps, drawings and Web graphics. Sketsa is a vector drawing application based on SVG (scalable vector graphics), a graphics format and technology based on XML.
Almost all illustration programs also include paint and image editing tools for raster images, but they lack the functionality of programs such as Adobe Photoshop, Corel PAINTER, Microsoft Paint and Jasc Paint Shop Pro. Conversely, these raster-based paint and image-editing programs lack the vector-based tools you find in illustration programs, and they aren't all that useful for working with geospatial data. You can import a raster image from a GIS program, but that's about it. Most paint and image editing programs don't use projects or geometric coordinate systems, and they don't work with shapefiles, grid files or other common geospatial formats.
Adobe Photoshop is predominantly a paint and image editor program, but it also has vector-based tools for creating paths, shapes and text. I've imported CAD and geospatial data into Photoshop numerous times and then used the paint and fill tools to add visual interest to data. One significant problem is that once a geospatial image, such as a GeoTIFF file, is brought into a program such as Photoshop, it doesn't maintain any of its geospatial data.
One approach to buying illustration software is to purchase suites of programs that are bundled together and sold at a price much lower than the combined cost of the individual programs. Integrated graphics suites combine functionalities such as image editing, illustration, Web design, page layout, typography functionality and other digital tools in one package. Because these programs typically are developed by the same company, they work together smoothly.
CorelDRAW Graphics Suite X3 includes photo-editing features, illustration and page layout tools, bitmap-to-vector tracing with Corel PowerTRACE, interactive fit-text-to-path tools, color palette tools, and other design-oriented tools.
Adobe's Creative Suite includes Photoshop, Illustrator, InDesign, GoLive and Acrobat in one package. In my office, we have Adobe CS loaded on all computers because it helps workers integrate graphics into a variety of different applications.
GIS and Illustrations
Ideally, when moving files from a GIS program to an illustration program, you want to preserve layers, transparency, editable text, object geometry and other characteristics. Most illustration programs don't have the ability to do this, but some take the integration of geospatial data seriously.
Avenza's MAPublisher 7 and MAPublisher LT 7 are suites of Xtras for Freehand and plug-ins for Illustrator that provide GIS tools for working with geospatial data. They allow you to import GIS data files directly into Illustrator and Freehand while still maintaining all of the geospatial attributes attached to that data. You also can incorporate GIS object management tools such as feature selection and query logic tools for easy data selection. The software provides several cartographic and GIS tools that are added to the menu structure of both Illustrator and Freehand.
Some of the data that MAPublisher can import includes shapefiles, ArcInfo E00 files, MapInfo, MicroStation (DGN), AutoCAD (DXF), USGS (U.S. Geological Survey) digital line graph files and other geospatial formats. Once data is loaded, it's fully editable, so you can make changes, add new attributes and create new data from scratch.
Canvas 9 GIS Mapping Edition (also called Canvas w/GIS+) is a full-featured GIS data visualization and publishing solution. Basically, GIS modules have been added to the core functionality available in Canvas X. Canvas is a unique program—it has tools that you might expect to find in CAD, illustration and image-editing programs. It's a good choice for someone who needs to do a little bit of everything.
Canvas X with GIS+ includes a broad range of visualization tools for editing, compositing, aligning and creating graphic images (figure 1). The bottom line for me, though, is its ability to open up shapefiles and other types of GIS data in an editable format. It's also a pretty simple process to open a shapefile, make changes, add CAD drawings and then save the whole thing in an encrypted PDF or other shareable format.
Figure 1. Created using Canvas X with GIS+, a map of a recommended evacuation route shows how shapefiles, GeoTIFFs and traditional graphics combine to add GIS data to maps. Courtesy of ACD Systems of America.
Canvas X uses most of the common coordinate references systems, projection systems and geodetic datums. It supports more than 80 different file formats, including shapefiles, MapInfo format, USGS digital line graphs, TIGER, MrSID, GML, SDTS, and GeoTIFF files, just to name a few. One of the biggest advantages of this kind of approach is that everything you create is in a georeferenced environment, so it has a real location in space. You can use the same coordinate systems, projections and datums that you would use in a GIS program. You can also reference other aerial photographs and raster images by using an image warp technique, and these images then can be exported to a GIS program.
Map attributes are maintained as part of imported geo-referenced files and relational databases. Attributes that have been assigned to map objects can be edited and saved, and map symbols can be replaced dynamically. I was impressed with the labeling capabilities—there are four different types of editable layers that are much better than you find in most GIS programs.
Working with a program like Canvas X helps streamline your workflow because you have less need to translate geospatial data into some other format for inclusion in an illustration file that then has to be retranslated to bring it back into a GIS program.
Tools for the Job
GIS users are interested in tools that help them produce high-quality maps. Until GIS programs include all of the tools we need, we'll continue to explore other ways to use illustration programs.
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.