create polyline automatically

[Tamim]

Hi, can anyone help with this?
I need a polyline to be created automatically. I draw a line, then I select an existing polyline, and wherever I drop the point, a new polyline should be created.
Sample CAD file is attached.
Each line distance should be 0.1 ft.
Please help with this.

Routes.dwg

[BIGAL]

Try this. Note only do one direction at a time do lefts exit and repeat to do rights.

 

; https://www.cadtutor.net/forum/topic/98817-create-polyline-automatically/
; Custom draw pline by Alan H Nov 2025

 Checking if pline is CW or CCW and set to CCW
; Orignal idea  by Kent Cooper, 1 August 2018 Offsetinorout.lsp
; By Alan H July 2020

; (defun c:wow ( / co-ord ht pt0 pt1 pty1a pt2 pt2a ht oldsnap)
(defun c:wow ( / )
(defun AH:chkcwccw (ent / objnew area1 area2 obj minpoint maxpoint)
  (setq obj (vlax-ename->vla-object ent))
  (vla-GetBoundingBox obj 'minpoint 'maxpoint)
  (setq pointmin (vlax-safearray->list minpoint))
  (setq pointmax (vlax-safearray->list maxpoint))
  (setq dist (/ (distance pointmin pointmax) 20.0))
  (vla-offset obj dist)
  (setq objnew (vlax-ename->vla-object (entlast)))
  (setq area1  (vlax-get objnew 'Area))
  (vla-delete objnew)
  (vla-offset obj (- dist))
  (setq objnew (vlax-ename->vla-object (entlast)))
  (setq area2  (vlax-get objnew 'Area))
  (vla-delete objnew)
  (if (> area1 area2)
    (command "Pedit" ent "R" "")
  )
(princ)
)

(setq oldsnap (getvar 'osmode))
(setvar 'osmode 0)

(setq pt1 (getpoint "\nPick 1st point "))
(setvar 'osmode 128)
(setq pt2 (getpoint pt1 "\nPick 2nd point on object "))
(setvar 'osmode 0)

(setq pt0 (polar pt1 (/ pi 2.0) 4.0))
(command "pline"
  (setq pt1a (polar pt0 0.0 1.85))
  (setq pt2a (polar pt1a (* 1.5 pi) 2.2))
  (setq pt3 (polar pt2a pi 3.7))
  (setq pt4 (polar pt3 (/ pi 2.0) 2.2))
  "C"
)

(setq ent (car (entsel "\Pick End Rectangle ")))
(AH:chkcwccw ent)

(setq co-ord (mapcar 'cdr (vl-remove-if-not '(lambda (x) (= (car x) 10)) (entget ent))))
(setq mp (mapcar '* (mapcar '+ (nth 1 co-ord) (nth 2 co-ord)) '(0.5 0.5)))
(setq pt4 (polar mp (* 1.5 pi) (* 0.4 (distance (nth 0 co-ord) (nth 1 co-ord)))))
(setq pt5 (mapcar '* (mapcar '+ (nth 0 co-ord) (nth 3 co-ord)) '(0.5 0.5)))
(setq pt3 (list (car pt2) (cadr pt4)))
(command "pline" pt0 pt1 pt2 pt3 pt4 pt5 "")

(while (setq pt6 (getpoint "\nPick 1st point Enter to exit "))
 (setq ang (angle pt2 pt6))
 (if (and (>= ang  (/ pi 2.0))(<= ang (* 1.5 pi)))
 (progn
  (setq pt0 (list (car pt6)(- (cadr pt0) 0.1)))
  (setq pt1 (list (car pt6)(- (cadr pt1) 0.1)))
  (setq pt2 (list (- (car pt2) 0.1)(- (cadr pt2) 0.1)))
  (setq pt3 (list (- (car pt3) 0.1)(- (cadr pt3) 0.1)))
  (setq pt4 (list (- (car pt4) 0.1)(- (cadr pt4) 0.1)))
  (setq pt5 (list (- (car pt5) 0.1)(cadr pt5)))
)
 (progn
  (setq pt0 (list (car pt6)(- (cadr pt0) 0.1)))
  (setq pt1 (list (car pt6)(- (cadr pt1) 0.1)))
  (setq pt2 (list (+ (car pt2) 0.1)(- (cadr pt2) 0.1)))
  (setq pt3 (list (+ (car pt3) 0.1)(- (cadr pt3) 0.1)))
  (setq pt4 (list (+ (car pt4) 0.1)(- (cadr pt4) 0.1)))
  (setq pt5 (list (+ (car pt5) 0.1)(cadr pt5)))
 )
 )
 (command "pline"
  (setq pt1a (polar pt0 0.0 1.85))
  (setq pt2a (polar pt1a (* 1.5 pi) 2.2))
  (setq pt3a (polar pt2a pi 3.7))
  (polar pt3a (/ pi 2.0) 2.2)
  "C"
 )
 (command "pline" pt0 pt1 pt2 pt3 pt4 pt5 "")
)

(setvar 'osmode oldsnap)
(princ)
)

(C:wow)