ptexport - Lisp untuk AutoCAD

Lisp ini berguna untuk mengkonversi koordinat titik-titik dari polyline (2DPolyline saja) dari file CAD (.DWG atau .DXF) kedalam file teks (.txt). Hasil dari konversi ini merupakan koordinat ruang yang dinyatakan dalam bentuk nilai X, Y, dan Z dari suatu titik. Sangat berguna dalam melakukan pengolahan data mengenai pemetaan (Topografi dan Bathymetri) serta pengolahan data turunannya. Misalnya untuk mendapatkan file .XYZ yang digunakan sebagai input data pada software SMS (Surface Water Modelling), dengan menggunakan lisp ini file .XYZ tersebut akan didapatkan secara mudah dan cepat. 

; ----------------------------------------------------------------------
;             (Export LWPOLYLINE Vertices & Points to File)
;            Copyright (C) 2000 DotSoft, All Rights Reserved
;                   Website: http://www.dotsoft.com
; ----------------------------------------------------------------------
; DISCLAIMER:  DotSoft Disclaims any and all liability for any damages
; arising out of the use or operation, or inability to use the software.
; FURTHERMORE, User agrees to hold DotSoft harmless from such claims.
; DotSoft makes no warranty, either expressed or implied, as to the
; fitness of this product for a particular purpose.  All materials are
; to be considered ‘as-is’, and use of this software should be
; considered as AT YOUR OWN RISK.
; ----------------------------------------------------------------------

(defun c:ptexport ()
  (setq sset (ssget '((-4 . "
                      (0 . "LWPOLYLINE")(-4 . "OR>"))))
  (if sset
    (progn
      (setq itm 0 num (sslength sset))
      (setq fn (getfiled "Point Export File" "" "txt" 1))
      (if (/= fn nil)
        (progn
          (setq fh (open fn "w"))
          (while (< itm num)
            (setq hnd (ssname sset itm))
            (setq ent (entget hnd))
            (setq obj (cdr (assoc 0 ent)))
            (cond
              ((= obj "POINT")
                (setq pnt (cdr (assoc 10 ent)))
                (princ (strcat (rtos (car pnt) 2 8) ","
                               (rtos (cadr pnt) 2 8) ","
                               (rtos (caddr pnt) 2 8)) fh)
                (princ "\n" fh)
              )
              ((= obj "LWPOLYLINE")
                (if (= (cdr (assoc 38 ent)) nil)
                  (setq elv 0.0)
                  (setq elv (cdr (assoc 38 ent)))
                )
                (foreach rec ent
                  (if (= (car rec) 10)
                    (progn
                      (setq pnt (cdr rec))
                      (princ (strcat (rtos (car pnt) 2 8) ","
                                     (rtos (cadr pnt) 2 8) ","
                                     (rtos elv 2 8)) fh)
                      (princ "\n" fh)
                    )
                  )
                )
              )
              (t nil)
            )
            (setq itm (1+ itm))
          )
          (close fh)
        )
      )
    )
  )
  (princ)
)

(princ "\nPoint Export loaded, type PNTEXPORT to run.")
(princ)