The magazine of the Melbourne PC User Group
Autodesk AutoCAD LT 97
Bernadette Houghton
 bernieh@iaccess.com.au


AutoCAD is expensive. Very expensive. You might find it hard to justify its purchase if you don't need such power, and particularly if you expect to use it rarely. The beauty of AutoCAD LT 97 is that not only is it several thousand dollars cheaper than its big brother, they share a common file format. Hence, you can freely open and edit files in either version without loss of data.

AutoCAD LT vs AutoCAD R14

Despite being a cut-down version of AutoCAD, LT 97 is no featherweight. It shares many features with AutoCAD R14 and even offers some yet to make their way into R14. Examples are The Content Explorer, PolarSnap and Microsoft IntelliMouse support, described below. Apart from its common file format with R14, LT is also backward-compatible with R12 and R13.

The main difference between R14 and LT is that LT is basically a 2D program, whereas R14 offers 3D capabilities as well. However, even though you can't create 3D objects in LT, you can edit them without losing the changes if you later open the drawing in R14. LT also omits a few high-end features, such as region modelling, external database connectivity and workgroup functionality. It isn't as flexible or customisable as R14, since it lacks support for the AutoLISP programming language, ActiveX controls, Visual Basic for Applications and third party add-ons.


Figure 1. AutoCAD LT 97 and the Content Explorer


Figure 2. LT's new online Help system

New features

The Content Explorer is an organiser for DWG files and any blocks or external references (xrefs) within those files. In AutoCAD terminology, a block is a group of objects that have been combined to create a single object, while an xref is a link to another drawing. Similar to a Windows Explorer pane, the Content Explorer also has an optional preview window so you can view drawings or blocks without opening a file. To add a block or xref to your drawing, you simply drag it from the Content Explorer and drop it on the page. You can organise your drawings and folders in any way you wish within the Content Explorer, and search for drawings or blocks by a range of criteria, such as name, description, folder and so on.

There are two new precision drawing tools, AutoSnap and PolarSnap. AutoSnap automatically highlights snap points as you move the cursor over an object, giving you a chance to verify a snap before choosing it. It also enables you to cycle through all the snap points available for selected objects. With PolarSnap, you can constrain snaps to specific angles or distances.

LT's interface is now compatible with Microsoft Office 97: there are look-alike menus and toolbars, tool-tips, dialog boxes, shortcut menus and shortcut keys. The most useful effect of these changes is that LT's commands are much closer to hand. With the new Object Properties toolbar, for example, you can quickly display and edit the properties of selected objects without wading through menus or issuing commmands.

Support for the Microsoft IntelliMouse means much smoother navigation of drawings; you can zoom and pan instantly with a touch of the IntelliMouse wheel. I found this feature much more convenient than clicking icons or navigating menus. In addition, you can now real-time pan and zoom in both Modelspace and Paperspace.

A new graphics subsystem speeds up operations such as opening and closing files, re-gens, zooms and pans, and text display.

LT includes a set of integrated Internet tools, including support for the new 2D DWF vector file format. DWF files support embedded hyperlinks, are viewable with Web browsers and the Whip! plug-in, and have smaller file sizes for speedier transmission over the Internet. LT's Internet tools also enable you to insert drawings into LT directly from Web addresses and publish them directly to the Internet.


Figure 3. Learning Assistance multimedia tutorial


Figure 4. Learning Assistance tutorial topics

Greater user control over drawings includes the ability to control the drawing and plotting order of objects, and preview drawings (or part thereof) before printing.

Text editing improvements include support for paragraph text, True Type fonts and formatted text, as well as a new Find/Replace feature.

A new Layer and Linetype dialog box means that you can edit the properties of named objects from within a single dialog box; no more issuing of multiple commands. Another useful enhancement is the ability to change layers quickly by selecting the Make Object's Layer Current button and clicking an object.

Learning tools

"Light" though AutoCAD LT is when you compare it to its big sibling, it is still a complex program with a rather daunting interface. In view of this, it is comforting to know that there is a robust help system:

  • A revamped online Help, which looks and behaves much like a Web browser. You choose a topic or phrase from the Contents or Index, then select either the Concepts, Procedures or Reference button, depending on the type of information you're after. While this feature still needs some fine-tuning (e.g. there is no search facility, and you can't copy and paste any of the text), I definitely found it much easier and faster to use than the usual online Help.
  • Learning Assistance is a multimedia tutorial, also with a browser-like interface. Offering both text and audio-visual tutorials, Learning Assistance has a "Try It" option for each of its 50 lessons. With Try-It, you can practice what you've learnt directly in LT, using either your own drawings, or sample files. Learning Assistance is accessible within LT at any time. I found it easy to use, and the tutorials well explained.
  • Quick Tour offers a multimedia overview of basic LT concepts and capabilities for new users.
  • What's New is a multimedia presentation of LT's new features, designed for those upgrading from an earlier version.
  • Set up Wizards walk you through the steps of setting up measurements, scale, paper size and so on for new drawings.
  • A 500-page Getting Started Guide, which is well set out and extensively cross-referenced with the online Help.


Figure 5. Content Explorer in full view


Figure 6. Setting AutoSnap options


Figure 7. Layer and Linetype dialog box
Assessment

If you don't need an industrial-strength computer-aided design (CAD) program, yet do require 100 per cent AutoCAD compatibility, LT is a safe option. AutoDesk has targeted LT at new CAD users, occasional users who require 100 per cent DWG compatibility and those upgrading or switching from similar CAD software. Shipping with a large range of full scale, Electrical, Mechanical and Architectural symbols, I found it to be a complex, yet robust program. However, the learning aids are very effective and make AutoCAD LT 97 much easier to master.

Reprinted from the July 1998 issue of PC Update, the magazine of Melbourne PC User Group, Australia

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