IntelliCAD is a new CAD program from Visio Corporation, the maker of a widely sold program for business graphics. It is designed to compete directly against AutoCAD®, though it lacks some of AutoCAD's more complex features (specifically, solid modeling and connections to external databases). The program uses the technology of the OpenDWG Alliance (discussed in the last issue of the Newsletter, "The OpenDWG Alliance," Spring 1998, Vol. XI, no. 1) to read and write DWG files, AutoCAD's native file format.
I received a review copy and set out to test IntelliCAD. It is such a complete copy in terms of the command structure that even the keyboard commands are the same as those used in AutoCAD. Though, for reasons set out below, I did not use the program for long, the only AutoCAD commands I found to be different were the secondary commands for AutoCAD's viewpoint command. In that case, I found IntelliCAD's system for determining a viewpoint to be very difficult to use, but experience can make a big difference in such matters.
The test did not last long, because the program failed at one of the most basic jobs I asked of it. It did not properly deal with complex surfaces. I often create complex surfaces, made up of several connected ones, to model oddly-shaped walls or blocks. The seams between the individual surfaces can be suppressed so that they do not show, making the connected surfaces appear to be a single surface. In IntelliCAD I could mark the seams so that they would remain invisible, and everything seemed normal. When I asked for a hidden-line drawing (items in the background hidden by those in the foreground), however, the seams were visible, dividing the single surface into its constituent elements again. (I checked; opening the drawing in AutoCAD and asking for a hidden-line drawing gave me the proper image.) There were also problems with surfaces that should show a joint line between them - walls meeting at various angles. In those cases, the joints showed or not in an unpredictable way in hidden-line drawings. Once these problems with hidden line drawings became apparent, I did not continue to experiment with IntelliCAD.
I did try saving a file and opening it in AutoCAD to check for file compatibility. I found that DWG files made by IntelliCAD seemed to be standard DWG files to AutoCAD R14. They could be read by AutoCAD R14, and IntelliCAD could open R14 files in return. The latest release of AutoCAD (14.01), on the other hand, was a different story. IntelliCAD DWG files would open only after an error message stating that the file had not been written by AutoCAD. There seemed no other problems when opening an IntelliCAD file in AutoCAD. Reversing the process, however, proved to be impossible. Trying to open an AutoCAD R14.01 file in IntelliCAD was worse than ineffective; it caused the program to crash every time. (In this connection, it is worth noting that, according to a review; "DataCAD 8 for Windows 95/NT," by Geoffrey Moore Langdon, Cadence, August, 1998, pp. 58-66; DataCAD does provide full DWG read and write capability for R 14.01. DataCAD relies on the same OpenDWG Alliance software as IntelliCAD; so this problem should be fixed in short order.)
IntelliCAD has one significant feature that is missing in AutoCAD. More than one model may be open and in use at a given moment. That is a significant feature since it makes it possible to see and use two or more drawings at the same time, even cutting and pasting between them. AutoCAD should include this feature, as mentioned in the review of AutoCAD R14 ( "AutoCAD Release 14 - A Review," Winter 1998, Vol. X, no. 3).
IntelliCAD's low price and use of the DWG format virtually guarantee a market for the program. The ability to use multiple files at the same time makes it even more likely that the program will be well received. If the bugs can be worked out, the use of common AutoCAD commands will make that all but certain. (IntelliCAD, Visio Corporation, 520 Pike Street, Suite 1800, Seattle, WA 98101; 800-248-4746. There seems to be no "list price," but retail is about $310, with discounts available from the manufacturer for academic use.)
-- H. Eiteljorg, II
To send comments or questions to the author, please see our email contacts page.
For other Newsletter articles concerning issues involved in using CAD in archaeology and architectural history, consult the Subject index.
Next Article: Software Comment: ToolPac 3.0
Table of Contents for the Fall, 1998 issue of the CSA Newsletter (Vol. XI, no. 2)
Table of Contents for all CSA Newsletter issues on the Web
Return to CSA Home Page