CAD Software

These CAD offerings simplify many tasks and open the possibility of including home-grown graphics in a variety of output formats.CAD has branched off from its origins as a drafting tool into a more accessible role as a drawing tool. Once, its primary use was for architectural or mechanical drafting'specialized activities such as designing buildings or fighter jets.The emphasis now is on using the computer for drawing, and that changes the picture considerably. Practically every government agency at some point could have a need to lay out office space, handle maps, create diagrams of processes or hierarchies, or generate graphics for a brochure or Web site. All of these activities now fall under CAD.CAD programs used to require sophisticated and dedicated hardware platforms that had fast CPUs, special graphics processors, expansive storage, large displays and graphical input devices. They still do, but now such machines sit on practically everyone's desk. Nearly all modern PCs have fast chips, built-in graphics processing, ample monitors, multigigabyte hard drives and mice. The rising level of hardware technology has made most machines CAD-capable.The personnel requirements for CAD have changed also. No longer do you need a degree from MIT'and saintlike patience'to handle computer-aided drawing. If you can drag and drop a graphical element with a mouse, you can create an adequate drawing.Besides, most CAD programs are now so object-oriented and forgiving that you can run your drawings past reviewers and easily tweak them to produce what is necessary.With the technological and human barriers surmounted, the main question is how to incorporate CAD properly into your work environment. This process is very much like finding the right piece to a complicated puzzle.The right CAD program has to satisfy a number of requirements before it finds a place on your machine. The first requirement is the intended final product of the CAD process.Different CAD programs have different strengths. Think what the ultimate output will be. A diagram in a white paper? The cover of a brochure? A map for daily use? A Web site image?The final output will go a long way toward narrowing the field of packages to consider. If you're trying to produce maps, a package that specializes in building space layout will not be of much help.A related consideration has to do with the specific features of each CAD package. You can view all of CAD's potential uses as a continuum of capabilities, ranging from high-end detailed architectural and mechanical specifications to everyday tasks such as creating a graphic to illustrate a brochure.Each specific CAD program spans some range of that continuum. Some clearly have features clustered at the high-end of capabilities. Some address everyday tasks with no possibility of producing detailed results. Others concentrate on everyday tasks but with some high-end features.Where do your typical tasks fall? If you have an office full of engineers, you naturally will lean toward programs with high-end features. If your office is more typical, requiring CAD for everyday tasks, you can probably ignore high-end features altogether and concentrate on packages that can handle what you do most.Also consider the audience for the images you produce. If your images show groundwater patterns and are intended for use by experts researching possible environmental problems, you probably want a package that can handle a lot of detail.But overall, the audience for most CAD-produced images falls into one of two categories: other agency employees and the general public.For the first, you might be generating organizational charts, office layouts or diagrams illustrating workflow for use within the agency. You can generally count on an in-house audience having a good deal of knowledge about the topic, allowing you to go into more depth with less background material.For the second, you may be creating a simple map, a brochure or a diagram showing the relationships among various agencies. When producing an image for the public, you cannot assume any special knowledge, so you need more support information and less overall detail. The general public also will likely have a greater need for visual information to help simplify understanding.When you narrow your list of CAD products, however, don't get too narrow. The ability to create general types of output with CAD is a powerful reason for using it in the first place; CAD capability could expand the types of documents you produce.You wouldn't buy a word processor that can only produce correspondence; a program that handles only maps might not make sense, either, unless you are certain that's all you'll ever do with it.The current operating system of choice for CAD is Microsoft Windows NT, but CAD packages are available for other varieties of Windows, as well as for Macintosh, Unix and Linux OSes.But there are other aspects of compatibility. Some CAD packages are more network-capable than others. This may be important if several users are collaborating on projects, or if CAD results must be shared in other ways.It is likely that the output from CAD will appear in another form in another application'a diagram will become part of a document in a word processor, for example, requiring you to move the image from the CAD program to the other application. This is most easily accomplished when the products are compatible.Users must consider graphics formats for input, output and storage.Many CAD makers have their own proprietary formats for storing their native graphics files, and each claims that its format is superior to others. It almost doesn't matter what format you store the native graphics in as long as the CAD program can produce output in any other format. But if you are sharing the native graphics files with other users, you should be able to store the graphics in a format that everyone can access easily. This will simplify the interaction and collaboration.It is important that the CAD program can import and use images in a great variety of input formats, and most CAD programs can, either embedding them without change in an image or translating them into the native format.Another consideration has to do with inputting non-graphics format, such as numerical data that becomes graphical data. For example, crime data applied to different areas on a map could turn those areas different colors depending on the numbers, visually indicating high and low crime rates. The input data might come from a spreadsheet or from tables of information.If you handle this kind of information, check carefully that the CAD program under consideration has the capability; most retail packages do not. In fact, this one factor could push you out of the off-the-shelf CAD market and into the higher-end products.Output formats are straightforward enough. The CAD program must be capable of producing output in a format appropriate to its destination. The prime example these days is producing .gif or .jpeg files for Web pages. But if your image is feeding into a page layout program, for instance, you must be able to create output that the next application can handle. This is usually not a problem'most CAD programs support a myriad of output formats'but it never hurts to check.An interesting feature of the burgeoning CAD market is the expanding selection of third-party add-on packages. These can transform general-purpose, everyday CAD programs into topic-specific applications.For example, there are many graphical symbol libraries. By using one of these in-depth symbol libraries, you can add the detail to an ordinary diagram that makes it useful to an expert audience.Other packages add capabilities, such as precision geometric drafting, to CAD programs.The tricky part is that add-on packages may be not one-size-fits-all. Granted, symbol libraries are usable by almost any CAD program. But the packages that add capabilities are usually tuned to a specific program's application programming interface. Add-on vendors most often orient their products toward CAD heavyweights, such as Autodesk Inc.If you have your eye on certain add-ons'and there are a lot, for almost any application'take compatibility into account. It may influence your decision about which CAD program to buy.XXXSPLITXXX-