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Comment by stew-j | Hacker News Reader

Our company wrote C++ and Ruby wrappers around BRL-CAD a number of years ago for scripted CAD, here is the tutorial for the radio example:

https://mirrors.sarata.com/non-gnu/tovero/Tovero_tutorial.pd...

We used it for a few small projects. BRL-CAD also has Tcl scripting.

We've currently switched to pure Common Lisp and F-rep modeling for scripted CAD. This is the old CL one (again wrapped C++) we are porting:

https://github.com/JMC-design/tovero

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That radio tutorial conversion is awesome.

Looks like the code is at http://svn.savannah.gnu.org/viewvc/tovero/trunk/ ? That's some impressive work, particularly some of the advanced geometry entity mapping going on in there.

Thanks! That is the right repo. If you want to use it, I hold the copyright and we could relicense it.

"My kingdom for a voice" [1] or maybe "My kingdom for a horse" [2] we did post an item about it on the BRL-CAD mailing list. The Common Lisp community didn't really notice Tovero 2.0 for Common Lisp either.

I was actually thinking about trying a Common Lisp wrapper of BRL-CAD, or maybe doing a native CL port.

[1] REM, Document, "King of Birds", 1987 (Anybody know a good marketer?)

[2] Shakespeare, Richard III, Act 5 Scene 4 (a Tovero is a type of horse)

It looks like your e-mail was the victim of my paternity leave... it's still in my inbox. I do recall Dr. Rai commenting on your post, but didn't get a chance to explore it in any detail at the time.

Remotely related, I've always thought a really fun lisp project would be to create an Emacs major mode for BRL-CAD. Either something to explore .g data (like tar mode) or an interactive editor like mged with lisp wrapping BRL-CAD's libged editing library.

> It looks like your e-mail was the victim of my paternity leave

10 years is generous paternity leave. :) Seriously though, no hard feelings, separating the wheat from the free software chaff takes time--ask me how I know.

> interactive editor like mged with lisp wrapping BRL-CAD's libged editing library

That interests me!

IME, I have found S-expressions to be an elegant, succinct way of expressing geometric models (especially in the F-rep domain):

https://github.com/JMC-design/tovero/blob/master/examples/ro...

I wrote a referencing counting C++ reader/writer for S-expression models like that directly into Open Inventor, in place of the IV (VRML) format, avoiding the use of CL.

Emacs has a C FFI, IIRC, so it should be possible to develop a S-exp formatted BRL-CAD model in elisp, with the right C shims--giving a live-coding, REPL experience for building BRL-CAD models.

Thanks for your work on BRL-CAD!

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