graph_pic.lisp

(defparameter *max-label-length* 30)

(defun dot-label (exp)
  (if exp
      (let ((s (write-to-string exp :pretty nil)))
        (if (> (length s) *max-label-length*)
            (concatenate 'string (subseq s 0 (- *max-label-length* 3)) "...")
            s))
      ""))

(defun nodes->dot (nodes)
  (mapc (lambda (node)
                (fresh-line)
                (princ (dot-name (car node)))
                (princ "[label=\"")
                (princ (dot-label node))
                (princ "\"];"))
        nodes))

(defun edges->dot (edges)
  (mapc (lambda (node)
            (mapc (lambda (edge)
                          (fresh-line)
                          (princ (dot-name (car node)))
                          (princ "->")
                          (princ (dot-name (car edge)))
                          (princ "[label=\"")
                          (princ (dot-label (cdr edge)))
                          (princ "\"];"))
                  (cdr node)))
        edges))

(defun dot-name (exp)
  (substitute-if #\_ (complement #'alphanumericp) (prin1-to-string exp)))

(defun dot->png (fname thunk)
  (with-open-file (*standard-output*
                   fname
                   :direction :output
                   :if-exists :supersede)
                  (funcall thunk))
  (ext:shell (concatenate 'string "dot -Tpng -O " fname)))

(defun graph->png(fname nodes edges)
  (dot->png fname 
            (lambda()
                   (graph->dot nodes edges))))

(defun graph->dot (nodes edges)
  (princ "digraph{")
  (nodes->dot nodes)
  (edges->dot edges)
  (princ "}"))

(defun uedges->dot (edges)
  (maplist (lambda (lst)
                   (mapc (lambda (edge)
                                 (unless (assoc (car edge) (cdr lst))
                                         (fresh-line)
                                         (princ (dot-name (caar lst)))
                                         (princ "--")
                                         (princ (dot-name (car edge)))
                                         (princ "[label=\"")
                                         (princ (dot-label (cdr edge)))
                                         (princ "\"];")))
                         (cdar lst)))
           edges))

(defun ugraph->dot (nodes edges)
  (princ "graph{")
  (nodes->dot nodes)
  (uedges->dot edges)
  (princ "}"))

(defun ugraph->png (fname nodes edges)
  (dot->png fname
            (lambda ()
                    (ugraph->dot nodes edges))))