Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: CAD Programs

[Subject Prev][Subject Next][Thread Prev][Thread Next]
-----Original Message-----
From: Mark Middlebrook <MarkMid(--nospam--at)>
To: 'SEAOC List' <seaoc(--nospam--at)>
Date: Wednesday, November 05, 1997 12:23 PM
Subject: RE: CAD Programs


You've had better luck than I in using DWG files from other CAD programs.
There was a review in CADALYST or CADENCE not long ago that tested the DWG
file compatibility of a number of CAD programs (sorry, I can't locate the
issue at the moment). The reviewer encountered significant problems in all
of the programs except for AutoCAD LT. Ralph Grabowski's article "Drawing
Translation" in the January 1997 issue of CADENCE does a good job of
discussing the many complexities.

Mark, I don't have it licked yet. Remember, Visual Cadd is no longer on the
market, has been purchased by Corel and then sold to IMSI before the beta's
had been completed. At this time, the only strong reliable feature has been
the DWG conversion ability. It may be the only reason that I have kept the
My comments were meant to downplay the DWG file format as a growing
standard. Look in almost every ad for a low cost CAD program and you will
almost always see that it reads and writes to DWG format. Design Cad,
Mini-Cadd, Visual/Corel Cad Technical/Visual Cad (again), Autocad Lt (yes
it's still fair to mention another AutoDesk Product), TurboCad, ArchiCad,
and I'm sure others.
Although conversion problems in the other programs (except Visual Cadd) have
problems) it can only be a short time before they are either resolved, or
the code is released from AutoDesk to assure accross the board platform
compatibility.  I am sure than AutoDesk is not afraid to lose market shares
to IMSI, Diehl Graphsoft or any other larger CAD developer. They do,
however, have much to gain by being the industry standard. I only wish that
viewers were more readily available without having to access the program or
without having to buy a viewer that costs as much as Visual Cadd (there is
Dr. QuickDwg for around $50.00 but it is not perfect).

In any event, a particular CAD program's DWG file compatibility may be quite
adequate for a particular situation (or even more than adequate, as in your
examples). But there will be entities, properties, or settings that the CAD
program doesn't read and/or write in the way that AutoCAD does. That's the
nature of translation. And don't forget that the DWG file is a moving
target. How many CAD programs support R14 DWG (or DXF), including the new
entity types? Do all of them even fully support R13 DWG? For many people,
it's worth a lot not too have to worry about all this stuff.

This will still be a problem within AutoDesk products as users opt not to
upgrade. The more content a user is with his operating system and setup the
least likly he is to upgrade - especially when the newer features are not
slick enough to justify the expense.
None of my clients use Rel14 as yet, only one uses Rel13, another Rel12,
another DataCad, another MiniCad and the last ArchiCad.
The diversity is strong enough to warrant a standard and the winner appears
to be AutoDesk. I don't feel that the target is moving fast enough to become
a concern. Each developer wants to keep up with the competition and will
more than likely issue upgrades to AutoDesks latest format or simply (as
they do now) ask the AutoCad user to save his file in Rel12 format. As far
as features that are unique to 13 or 14, this may be a problem if it
requires conversion, but historically, 99 percent of all of the drawing that
I do could have been done on release 2.5.

Yes, each of the CAD programs has customization features. But none has had
AutoLISP or the other AutoCAD customization interfaces, which means that
they can't run third party applications written for AutoCAD, and they can't
use the zillions of little AutoLISP utilities and programs that are
available. That apparently will change now that Visio and IMSI are adding
AutoLISP emulation, which is a good thing. But then there'll be another
compatibility issue (AutoLISP emulation), not to mention ADS and
This is a very important issue for those who use add-on packages and those
that have created custom routines over the years. However, the low end
packages generally allow for macro creation as well as object oriented
programing. Even with this ability, I believe that the majority of users
never tap into these advance features. What AutoDesk misses is that with the
thousands of little lisp routines available on user group sites, many of
them are incorporated into the low end packages as standard features. These
include line repair (joining), matching and filtering (Visual Cadd's
filtering ability is far superior to AutoDesk Release 13 features),
Thumbnail graphic symbol libraries, direction pick with length entry (it
took Acad to release 13 to make this a standard), reference points, and many
more of the features not standard in a $3,700.00 package.

I'm not defending Autodesk, AutoCAD, or AutoCAD's price. In many ways
Autodesk does have design firms over a barrel - in the same way that
Microsoft does vis-à-vis operating systems (and, increasingly, business
applications). But that's life. In my view it's usually easier and makes
better business sense to use software that's standard and widely supported.

- Mark Middlebrook  73030.1604(--nospam--at)  MarkMid(--nospam--at)

Mark, I believe that there is no room for AutoDesk to get overconfident in
their market shares. Programs like Mini-Cad have a very strong following
from their history with MacIntosh machines. Although I am not an admirer of
Mini-Cad, a neophyte user is a prime target to such as program whose
programing ability is easier to use and far superior to AutoDesks Autolisp
or ADS. With a retain cost under $600.00 a user would be foolish not to
consider it in their options.
The middle market is very competitive today and is trying to capture
compatibility with AutoCad users to offer an alternative system.
The primary strength of AutoDesk is in its longevity and ability to support
an existing user base. It is also desirable to others than demand
compatibility with large clients who make equal demands upon them.
The other advantage is that they released a program like AutoCad LT (and
developed Generic Cadd which was written by the Numera Software - the same
people that brought us Visual Cadd). AutoDesk now has to compete and
possibly loose market shares from their higher end product to their lower
market product. Especially as the list of features equal or supperior to
those offered in AutoCad 13 or 14 continues to grow.

One final comment. Generic Cad was a very easy intuitive tool that AutoDesk
must have realized had strong market appeal. When they purchased the code,
they opted not to hire the development team. This led to the development of
Visual Cadd - the first completely Windows Compatible 32 bit program. Where
Rel13 C4 failed to do, Visual Cadd did very well. This included opening as
many windows as memory would allow and cutting and pasting between windows
in true OLE or DDE fashion. The company focused on taking all of the extras
including a symbol library of structural and architectural shapes, the
ability to modify and work with attributes, 2-letter commands (the strength
of Generic Cadd), interactive menu support (mouse button menus changed with
the different commands), customized toolbars, "aerial views", on screen
toolbars and much more. It took AutoDesk through release 13 to offer these
features for $3,200.00 more.

AutoDesk is no longer in a position to stand on their laurals in a product
that is quickly becomming outdated. They need new and innovative features to
justify the $500.00 upgrade price to a user satisfied to stay productive on
the system that they already are comfortable with. What's next????

Best regards