3D lisp for twisted wire pairs

I looking for a lisp that will do twisted wire pairs, as in twisted
lockwire. I found some 2D but no 3D. Anyone have one?

 

You're looking for a double helix lisp. Good luck with that. A simpler way
would be to create 1 twisted wire using a spiral pline and a circle,
extruding it along the spiral's path and mirror it around a point satisfying
the condition of creating a double helix. Here's a lisp that creates 3D
sprials very easily.

Happy DNA making.


;;; A.Dudek
;;; 3DSPIRAL.LSP
;;; Copyright (C) 1993 by Autodesk, Inc.
;;;
;;; Permission to use, copy, modify, and distribute this software
;;; for any purpose and without fee is hereby granted, provided
;;; that the above copyright notice appears in all copies and that
;;; both that copyright notice and this permission notice appear in
;;; all supporting documentation.
;;;
;;; THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT EXPRESS OR IMPLIED
;;; WARRANTY. ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR
;;; PURPOSE AND OF MERCHANTABILITY ARE HEREBY DISCLAIMED.
;;;
;;; DESCRIPTION
;;;
;;; This is a programming example.
;;;
;;; Designed and implemented by Kelvin R. Throop in January 1985
;;;
;;; This program constructs a spiral. It can be loaded and called
;;; by typing either "spiral", "3dspiral" or the following:
;;; (cspiral <# rotations> <base point> <horiz growth per rotation>
;;; <points per circle> <start radius>
;;; <vert growth per rotation>).
;;;
;;;
;;; Revision 3/9/95 Anthony Dudek
;;; Fixed problem of not drawing a full 360 degree helix when using only one
;;; rotation of 3dpolyline
;;;

(defun myerror (s) ; If an error (such as CTRL-C) occurs while this
command is active...
(if (/= s "Function cancelled")
(princ (strcat "\nError: " s))
)
(setvar "cmdecho" ocmd) ; Restore saved modes
(setvar "blipmode" oblp)
(setq *error* olderr) ; Restore old *error* handler
(princ)
)

(defun cspiral (ntimes bpoint hfac lppass strad vfac /
ang dist tp ainc dhinc dvinc circle
dv
)

(setvar "blipmode" 0) ; turn blipmode off
(setvar "cmdecho" 0) ; turn cmdecho off
(setq circle (* 3.141596235 2))
(setq ainc (/ circle lppass))
(setq dhinc (/ hfac lppass))
(if vfac
(setq dvinc (/ vfac lppass))
)
(setq ang 0.0)
(if vfac
(setq dist strad
dv 0.0
)
(setq dist 0.0)
)
(if vfac
(command "_3dpoly") ; start spiral ...
(command "_pline" bpoint) ; start spiral from base point and...
)
(repeat ntimes
;;;
;;; section of revised code

(if (= ntimes 1) ; if the number of
; rotations is 1
(repeat (1+ lppass) ; then calculate points
; one extra time to allow
; for the missing polyline segment at the end of
; the rotation
(setq tp (polar bpoint
(setq ang (+ ang ainc))
(setq dist (+ dist dhinc))
)
)
(if vfac
(setq tp (list (car tp) (cadr tp) (+ dv (caddr tp)))
dv (+ dv dvinc)
)
)
(command tp) ; continue to the next point...
) ; close inner repeat
;;;
; otherwise
(repeat lppass
(setq tp (polar bpoint
(setq ang (+ ang ainc))
(setq dist (+ dist dhinc))
)
)
(if vfac
(setq tp (list (car tp) (cadr tp) (+ dv (caddr tp)))
dv (+ dv dvinc)
)
)
(command tp) ; continue to the next point...
) ; close inner repeat
) ; close if
) ; close main repeat
(command "") ; until done.
(princ)
) ; close defun

;;;
;;; Interactive spiral generation
;;;

(defun C:SPIRAL (/ olderr ocmd oblp nt bp cf lp)
(command ".undo" "group")
(setq olderr *error*
*error* myerror
)
(setq ocmd (getvar "cmdecho"))
(setq oblp (getvar "blipmode"))
(setvar "cmdecho" 0)

(initget 1) ; bp must not be null
(setq bp (getpoint "\nCenter point: "))
(initget 7) ; nt must not be zero, neg, or null
(setq nt (getint "\nNumber of rotations: "))
(initget 3) ; cf must not be zero, or null
(setq cf (getdist "\nGrowth per rotation: "))
(initget 6) ; lp must not be zero or neg
(setq lp (getint "\nPoints per rotation <30>: "))
(cond ((null lp) (setq lp 30)))
(cspiral nt bp cf lp nil nil)
(setvar "cmdecho" ocmd)
(setvar "blipmode" oblp)
(setq *error* olderr) ; Restore old *error* handler

(princ)
(command ".undo" "end")
)

;;;
;;; Interactive spiral generation
;;;

(defun C:3DSPIRAL (/ olderr ocmd oblp nt bp hg vg sr lp)
(command ".undo" "group")
(setq olderr *error*
*error* myerror
)
(setq osn (getvar "OSMODE"))
(setvar "OSMODE" 0)
(setq ocmd (getvar "cmdecho"))
(setq oblp (getvar "blipmode"))
(setvar "cmdecho" 0)
(initget 1) ; bp must not be null
(setq bp (getpoint "\nCenter point: "))
(initget 7) ; nt must not be zero, neg, or null
(setq nt (getint "\nNumber of rotations: "))
(initget 7) ; sr must not be zero, neg, or null
(setq sr (getdist bp "\nStarting radius: "))
(initget 1) ; cf must not be zero, or null
(setq hg (getdist "\nHorizontal growth per rotation: "))
(initget 3) ; cf must not be zero, or null
(setq vg (getdist "\nVertical growth per rotation: "))
(initget 6) ; lp must not be zero or neg
(setq lp (getint "\nPoints per rotation <30>: "))
(cond ((null lp) (setq lp 30)))
(cspiral nt bp hg lp sr vg)
(command "_CIRCLE" bp (* 7 sr))
(setvar "cmdecho" ocmd)
(setvar "blipmode" oblp)
(setq *error* olderr) ; Restore old *error* handler
(princ)
(command ".undo" "end")
(setvar "OSMODE" osn)
)
(defun C:3s ()
(C:3dspiral)
)
;;;
(princ "\t3DSPIRAL.lsp loaded")
(princ)

 

Thanks

 

Thanks


I had to read twice. I missed your reply the first time !
My pleasure, friend.

Dr Fleau