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Comment by smoyer | Hacker News Reader

And Auto-CAD had a Lisp engine in the '80s ... You could automate almost any function of the drawing system, build "macros" as well as patterns and even alter the DXF generation.

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AutoCad got AutoLisp as an update to R6 in January 1986. AutoCad got solid modelling in R11 with the "Advanced Modelling Extension" add-on in 1990.

The whole history of AutoCad's feature evolution is that of a successful startup. There's an overview on AutoDesk's website:

http://autodesk.blogs.com/between_the_lines/autocad-release-...

I think it was release 2.18, retroactively named R6 maybe. John Walker and I hacked up a p.d. thing called xlisp by David Betz, removing some of the best bits (the 'X' parts) and fitting it into its own 64k 'small model' (x86) segment. I was a bit of a lisp nut, but even I (product manager at the time too) thought lisp as a 'macro language' for AutoCAD was a tinge crackers. Glad we did it though!

Yes, according to the timeline, it was 2.18, but it lists 2.1 as R6, so despite it's huge impact in allowing the creation of tools like AEC-Architectural it apparently doesn't get its own integer. As a scripting language it seemed to me a pretty good choice, because sat reasonably well with the command-line based interface in that it somewhat reflected its <command> <argument>* format.

And of course in the 1980's Lisps were tech's "the sharing economy". One of the reasons I went to vocational school to study drafting was to get my hands on AutoCad to get my hands on AutoLisp to get my hands on a Lisp. In 1991, I was doing timed Cad competitions using R10. My secret weapon was twenty minutes writing my own "PGP" command aliases in AutoLisp with edlin before I started drawing. That's how I won my copy of R11.

So I'm glad you did it too. Thanks.

> And of course in the 1980's Lisps were tech's "the sharing economy". One of the reasons I went to vocational school to study drafting was to get my hands on AutoCad to get my hands on AutoLisp to get my hands on a Lisp. In 1991, I was doing timed Cad competitions using R10. My secret weapon was twenty minutes writing my own "PGP" command aliases in AutoLisp with edlin before I started drawing. That's how I won my copy of R11.

That sounds like a great story. Would you consider sharing it?

John Walker's The Autodesk File has his original strategy paper on this topic:

https://www.fourmilab.ch/autofile/www/chapter2_35.html

"Lisp?!?! Why the Hell did you pick the most arcane, obscure, and hopelessly-rooted-in-the-computer-science-department language in the world for an AutoCAD programming language? Over the next six months, all of us will have the opportunity to answer this question."

That was in 1985. Not so much has changed in 30 years :P

The AutoDesk File is a great resource for understanding startups and business.

You can still run Lisp commands on the commandline interface in AutoCAD. Or even as you type out command inputs. So for example, if you know that you just put in 187 for length, but the next line needs to be double that, you can type (* 2 187) when it's time to put in the length and AutoCAD calculates it.

I thought they turned it into a license feature (so LT doesn't have it, only the full version does)?

But yes, I found AutoLisp to be very useful for automating things. The place I used to work for had to have the CNC machines cut out differently sized shapes from a library of shapes, so I created functions to draw each library shape for me quickly.

This is a lot easier than trying to form four mutually tangent circular arcs into an oval by constructing everything by hand.

You are correct. I describe AutoCad LT as either "Fisher Price" AutoCAD, or AutoCAD without the useful stuff. Most people that use AutoCAD might as well be using Etch-A-Sketch...

I know... I had a hard time once trying to explain that the newer LT version was completely worthless to me because I needed the AutoLisp from the real version and that the "upgrade" gave me no useful features and merely made it impossible to automate anything.

Sure, I could construct everything by hand, but that's pretty unreasonable when I'm redoing the same basic shapes all day.

LT is the follow on to AutoSketch and marketed to those who don't find value from working in 3d. AutoDesk upbranded the product and raised the price point when they renamed it, and a lot of people who say they use AutoCad are using LT "instead". In fairness, there are a lot of people using AutoCad with color based plotting (style based was introduced with Acad2000 in 1999) and who don't use those "new features" like Paper Space and Xrefs (introduced in r11 in 1990). Making things is very much bound by traditions.

To be honest, when I used it, AutoLisp was really the only feature I cared about other than drawing basic 2D shapes. You could have left me with only points, lines, arcs and dimension text, as long as I had lisp to automate it all.

Yes, LISP is only present in Autocad Professional.

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