CAD-based software has had an almost hostage-like grip on companies. Anyone who uses computer-aided drafting has had a litany of complaints ranging from its lack of user-friendliness to the expense of its required modules.

But there have not been many other options. Over the years, civil engineering and surveying firms and their customers have come to accept inferior output from CAD-based design software on the theory that it performed at least some necessary functions.

Software manufacturers took advantage of the situation by not adapting CAD's core technology to the needs of civil/survey design. In other words, CAD was a helluva tool for designing car fenders, but not much help in creating surveying and civil engineering-related plans. It lacked the spatial and surface intelligence to accomplish that type of work unless the user added costly modules, with steep learning curves requiring never-ending user training.

ADD-ONS. Private firms and government agencies have had to use a wide variety of software. Almost all have been based on CAD and/or GIS (Geographic Information System), which use very different data structures intended for two divergent needs. For surveying and civil engineering, a variety of costly third-party modules have been added to do everyday tasks with coordinate geometry, contouring, legal-description generating and presentation systems.

But moduled software solutions can easily cost $10,000 per seat or more by the time training, support and upgrades are added. Include GIS, and a seat can double in price. This situation has created a new generation of CAD technicians who, for all practical purposes, have held their bosses hostage. Output from engineering and land surveying companies would come to a screeching halt if their CAD technicians walked out the door tomorrow.

There are significant technical complexities involved, too. CAD-based packages generate huge files that slow down system operations, require additional storage devices and create major download and transfer issues.

Fortunately, several vendors are starting to offer alternatives in terms of new technology, software and pricing. One example is a technology called CDIS (Coordinate Design and Information System) that fully integrates coordinate geometry, drafting and spatial intelligence into a powerful stand-alone package. As an engineering software developer, I began creating CDIS in 1983 to help bridge the gaps between surveying, civil engineering, GIS and land planning.

In a technology like CDIS, the drafting is a by-product of the original design input. Rather than being linked by some separate computation module, every arc and line is the end result of the original geometric coordinates. This virtually eliminates the need for drafting-only employees. Any competent employee knowledgeable in surveying, civil engineering, or planning can easily learn the basics in only one day of training, and can become extremely proficient in less than two weeks.

Better yet, some new CDIS products have innovative pricing structures. Some companies offer annual user license fees that include all updates and upgrades, ensuring that all customers use the same version at the same time. In this pricing structure, customers renew by choice each year, so that we vendors must continually work to satisfy them.

With great speed, extreme precision and ease of use, technologies such as CDIS offer higher productivity and profits. Consider this analogy. Only two decades ago, a survey crew of four people could collect about 80 measurements (points) in a typical day by using a transit and steel tape. With today's electronics, a two-person crew can measure 800 points with uncanny accuracy. This is a 10-fold increase in productivity with half the labor. And the profits are higher than ever before because rates have been changed to reflect the automation, production and quality of the work. Using new software technology in office work yields the same bonus.

In today's working environment, it is not uncommon for large plans to have hundreds of thousands of points. CAD-based systems often reference these items by point numbers, called nodes. But technologies such as CDIS name each point through its geometric identity; they work with actual coordinates rather than with node numbers, thereby saving computer memory.

ACCURACY. The spatial geometry of CDIS uses smaller files because it tracks shapes by name. To compute the area of an easement around a tract named "Jones Site," the user merely refers to that name. And because shapes are named, screen displays are instantaneous. The actual area can be calculated to the millionth of a square foot because of the high accuracy, up to 32 digits in some software. Plus, some new technologies use actual curve data in calculations.

This results in more accuracy than with existing GIS, which represents curves by a series of coordinates along a polygon. Yet CDIS manages the geometry of a large geographic region as easily as that of a highway intersection, and creates output files a fraction of the size of those created by CAD and GIS.

No wonder that CAD alternatives are starting to catch on. With higher performance standards, these affordable and user-friendly tools are beginning to change the software landscape for surveying, civil engineering, mapping and land planning. And at last, these alternatives are bringing an efficiency that has been lacking with CAD.

NamRichard Harrison, a developer of CDIS technology, is the president of SiteComp, Inc. in Golden Valley, Minn. He may be emailed at rharrison@sitecomp.net