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AutoCAD 2000 is the latest version of the world's most widely used CAD program. (Actually, there is yet a newer version, called AutoCAD 2000i, the i indicating the intention to include features that enable cooperative design over the Internet. AutoCAD 2000 is the latest version for CSA.) Over the years since AutoCAD first became the CSA standard it has undergone many changes. Initially those were improvements in the three-dimensional capabilities; then solids were added; then database linking; further refinements followed. By the mid-nineties, though, the basic package was more or less complete. The improvements in AutoCAD 2000 are therefore, in many respects, relatively minor. In terms of real day-to-day utility, though, there are some valuable additions.
The most long-awaited new feature is the ability to work with more than one model at a time. That has previously been possible only by running two AutoCAD sessions at once, not by having multiple windows, each with a different model, in a single session of the program. Now two models can be used at once. Happily, the ability to use more than one model at once is only the tip of the iceberg in terms of interaction between and among models. It is possible easily to take features from one model - layer specifications, linetypes, and text styles, for instance - and drop them into another. Of course, objects from one can be copied and pasted into another as well.
Unfortunately, the ability to work with multiple models has not been coupled with a simple way to work on one model in multiple windows. It is still possible to divide the primary window into smaller ones (called viewports), but the viewports themselves cannot be independently sized by the user. The feature AutoCAD calls paper space is more flexible in some ways but difficult to use effectively.
Other new features - individually valuable and very desirable as a group - make it possible to view models in better, more useful ways. In the past it was always possible to create a hidden-line drawing of a particular view. Now the user can work in hidden-line mode as well, seeing the model in a far more realistic mode while actually making additions or changes. In fact, it is possible to work in four different shaded modes as well, adding to and editing the model while seeing it more naturally. The possibilities for manipulating the user's viewpoint have also been significantly enhanced with the 3D Orbit command. Whatever the on-screen view, it can be manipulated in three-dimensions, in real time - in wire-frame, hidden-line, or shaded modes. All these new features together make working with and/or manipulating a model a great deal easier, especially when dealing with a model that is difficult to visualize.
The new display features do have a down-side. In prior version of AutoCAD, any redrawing of the screen image returned the screen to wire-frame mode, which is the normal working mode. Now one must explicitly re-select the wire-frame display mode. It is too bad that there isn't a quicker, simpler way to do that without adding another set of tool icons to the tool bar.
Other interesting new features:
Autodesk highlights the changes to the user menus, saying that they conform more closely to Microsoft® Office standards. The changes did not seem either noteworthy or particularly valuable. However, one change was - and still is - annoying. Finding the object snap dialog box now requires the user to remember that it is now found via the dialog box called Drafting under the pull-down menu Tools, though it is possible to add yet another batch of icons to the tool bar to gain access to the object snap settings more quickly.
Autodesk also changed the coordinate system icon. The new one seems intrusive, but this is hardly an important matter.
For the record, it should be said that AutoCAD 2000 can save files in R12, 13, and 14 DXF formats and R13 and 14 DWG formats. These may seem trivial or obvious features, but they can be extremely important for anyone working with colleagues who do not have the most recent version of the software.
Drawings made with AutoCAD 2000 have been used to illustrate the article about the excavation at Nemi in this issue of the Newsletter. The rendered views show how easy it is to use AutoCAD to do good rendering without enormous effort.
AutoCAD first introduced the potential to connect items in data tables to drawing entities in Release 12. It worked, but it was clumsy and a bit difficult to use. Transferring the links to Release 13 was ridiculously difficult, and upgrading for Release 14 added some new wrinkles, though the system seemed to work well. The connections in AutoCAD 2000 seem easier, and the way the entire database connection is laid out is far more useful and intuitive than previously (though not for tables with many fields, which can only be seen by scrolling across a wide row). However, setting up the system is still too difficult. It seems that the company assumes that the database links will be managed by full-time network administrators. The typical single user, though, must deal with far too much arcane vocabulary and for too many confusing set-up options when some form of a set-up "wizard" should be available. It was even possible to completely disable the database system by simply removing the label in one database connection dialog box. Only after the file accidentally renamed .UDL (that is, no name, only the UDL extension) in that dialog box had been renamed via the Windows NT Explorer® would the database connection system within AutoCAD operate again. That is inexcusable. (There also seems to be a strong pro-Microsoft software bias in the instructions and the default settings. Indeed, it is clear that Autodesk has decided that its future is closely tied to the future of Windows and that AutoCAD should be ever more tightly tied to Windows. That is probably not a negative - and may even be a benefit - for large firms, but it is certainly not a benefit for the academic community, where Microsoft is not so dominant.)
The database system did not seem to work reliably in the few experiments conducted at CSA. A DBF file was connected to the older propylon model, and linking entities from the model to rows in the table did not work reliably, regularly making connections from a given table row to more objects in the model than intended. Removing those incorrect connections is ridiculously difficult, requiring that each individual entity be disconnected through a multi-step process.
Putting one DBF data table into an Access® database seemed to yield more reliable linking, though not flawless. The various visual clues did not function predictably for either the DBF or the Access tables, though. All in all, the reliability of the current database connection system seemed suspect; so a second experiment was undertaken. Two new drawings were created, as were two new tables, one in Access 97 format and one in DBF format. Each drawing had one of the tables connected to it, and the processes were carefully recorded. This time there were two problems with connecting the Access table - two different unintended connections were created, but there were no problems with the DBF table.
The problems encountered seem to suggest that very minor deviations from the correct procedures can cause the process to go awry. It seems unlikely from the experiments conducted that there is a basic flaw in the software, but the data entry system is too easily compromised - in ways not seen by the operator.
The problems with the database connections suggested a look at the Autodesk Web site to see if there were upgrades for the program that should have been installed. Examining the pages in the support area was a very disappointing experience. The information about support upgrades and patches seems clearly intended for people who already know what they need. There seems to be no general explanation of the kinds of files available or, in general, who might need to use which one(s). There is apparently no single upgrade that would fix all known problems, since there are upgrades, peripheral drivers, and utilities, each in its own category, and, unbelievably, the second service pack requires users to install the first service pack before installing the second one. Even Microsoft does better than that, at least with Windows NTTM service packs.
There are also different upgrades for locked and unlocked versions of AutoCAD, with warnings about using the correct one - but no explanation of what locked and unlocked mean or how to distinguish between locked and unlocked versions. It seems that the user should know if his/her version is locked, but CSA's experience is probably typical. The CSA version is an academic version, but there is no hardware lock as there used to be. There is only an authorization code. Is that a lock? Information in the AutoCAD discussion group showed how to find out whether a given version is locked or not, but the CSA program did not display any of the possibilities specified; so the question remains unresolved.
The Web site is full of scripts and other indications of the high-tech world - but not evidence that the site is intended to present useful information to a variety of users, ranging from relatively unsophisticated designers who simply want to get back to work to computer experts dealing with large numbers of installations. In that sense, this Web site is very much in keeping with the general trend in Web sites, especially those of high-tech companies. They seem especially vulnerable to the need to display computer sophistication by showing elaborate pages and impressive graphics - but not particularly inclined to define the real purpose of the site and to make sure that purpose is accomplished with a minimum of wasted time.
The new features of this version are not crucial, but they are valuable. This is especially true of those involving the user interface - the ability to work with multiple models and the new ability to work in hidden-line or shaded made. The database connectivity problems experienced in CSA testing indicate a need for considerable care, but, all in all, this is a worthwhile upgrade for AutoCAD.
-- Harrison Eiteljorg, II
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For other Newsletter articles concerning the applications of CAD modeling in archaeology and architectural history, consult the Subject index.
Table of Contents for the Fall, 2000 issue of the CSA Newsletter (Vol. XIII, no. 2)
Table of Contents for all CSA Newsletter issues on the Web