I quite like the idea of being able to describe a house plan in a DSL. I’m thinking about doing the same thing as you (building a house) and would like to be able to generate a floor plan from code.

I’ll check back every now and then.
Thanks

(defmethod draw-door (renderer &params-related-to-doors)
  ...
  (draw-line renderer pt-a pt-b :weight 2)
  (draw-arc renderer center angle-1 angle-2 :weight 1))

Then, you would specialize draw-line and draw-arc based on the renderer.

(defmethod draw-line ((render opengl-renderer) pt-a pt-b &key (weight 1))
  ...)
(defmethod draw-line ((render cl-pdf-renderer) pt-a pt-b &key (weight 1))
  ...)

Still cogitating…. Thanks for the input.

CAD is pretty well locked up into expensive stuff like AutoCAD, or cheapie programs that do little.

I mean programs like AutoCAD, not necessarily Lisp code. I meant for you to look over how those programs work, and make your stuff work that way (because the CAD guys have done all this before). Look for AutoCAD packages. AutoLisp isn’t Common Lisp, but it’s close enough to figure out what to do. Look in places like this:

http://www.cadinfo.net/scripts/lisplib-software.cfm?areano=56

I’d also look at tutorials for AutoCAD or SolidWorks to see how they enter things like absolute coordinates and relative coordinates in their command lines.

What I wanted was very similar to what you wanted: a DSL for some graphic operations that I could sue to write programs that output to either OpenGL (for interaction), or DXF (to send to other people).

My impetus is that I’m designing a new house. So I wanted to be able to use Lisp forms to describe the house. Didn’t make it there the first time — I had Lisp code that described it. I have a pretty good background in OpenGL (been doing it since it was IrisGL), but little in CFFI so I’m of little use to the cl-opengl guys. And I also have done a lot of stuff in AutoCAD, and have a bit of code lying around that’s a sort of bad DSL for DXFs. really it’s just a with-open-dxf kind of thing and functions that write out the various elements.

So I had a program that drew my house, with code that looked like:

(defun draw-door (w x y z a r &optional (th 4))
  (if (wire w)
    (draw-door-w x y z a r th)
    (draw-door-t w x y z a r th)))

This isn’t so good, because I now have to write both the wireframe function and the texture function. And I’d have to add another in order to do DXf output.

So my solution is to do something like:

(defun draw-door (w x y z a r &optional (th 4))
  (add-line yadda yadda) ...)

to create an intermediate format. Then I’d instruct some renderer to use that format for its output. That output could be to my standard OpenGL model viewer in either wireframe or textured mode, or a DXF renderer, or PDF, or whatever.

You probably won’t find too much of my code out in the world. Though I’ve been doing code since the mid-70′s, I’ve only been doing Lisp for a few years. And most of my stuff is copyrighted by my employers.

You mention that your output is DXF or OpenGL. Your output from what? I’m having trouble Googling you by nym. (Actually, raito lisp and raito opengl both turn up lots of hits about cl-opengl where I cannot find raito in the body of the page at all.) I’d be interested to see what you’re working on.

I have been considering an cl-opengl floor-planning tool. I thought an intermediate language that produced nice output files was a simpler starting point for that since I wouldn’t have to deal with fonts in cl-opengl or keyboard input or mouse selection and stuff that would distract from what I really want right away: a nice looking floor plan.

I had thought about trying to specify rooms in terms of volumes instead… this room is the union of a rectangle this big and a rectangle this big where the bottom-left corner of the first rectangle is two feet further down the page than the bottom-right corner of the second rectangle. This makes inside-measurements vs. center-of-wall measurements easier. It makes marking exterior walls vs. internal walls harder unless one assumes that the exterior walls are obviously all walls on the exterior of the drawn portion. It does make doors easier though with things like: this room’s door is five feet left of the bottom right corner and opens into the room.