distance between two points of Polyline (Close / Open)

[Guest]

I find here this lisp

 

http://cadtips.cadalyst.com/distance/determine-distance-between-points-entity

 

(defun c:DBP (/ AT:DrawX AT:CycleThroughSS p1 ent p2 d1 d2 dlst)
 ;; Calculate distance between 2 specified points on curve object
 ;; Alan J. Thompson, 03.20.10 / 03.28.10 / 03.07.11 / 05.09.11

 (vl-load-com)

 (defun AT:DrawX (P C)
   ;; Draw and "X" vector at specified point
   ;; P - Placement point for "X"
   ;; C - Color of "X" (must be integer b/w 1 & 255)
   ;; Alan J. Thompson, 10.31.09
   (if (vl-consp P)
     ((lambda (d)
        (grvecs (cons C
                      (mapcar (function (lambda (n) (polar P (* n pi) d)))
                              '(0.25 1.25 0.75 1.75)
                      )
                )
        )
        P
      )
       (* (getvar 'viewsize) 0.02)
     )
   )
 )

 (defun AT:CycleThroughSS (ss / l i e)
   ;; Cycle through a selection set to choose one
   ;; ss - selection set
   ;; Alan J. Thompson, 03.30.11
   (if (eq (type ss) 'PICKSET)
     (if (eq (setq l (sslength ss)) 1)
       (ssname ss 0)
       (progn (princ "\n<Tab> to cycle through entities: ")
              (redraw (setq e (ssname ss (setq i 0))) 3)
              (while (eq (cadr (grread nil 10)) 9)
                (mapcar 'redraw (list e (setq e (ssname ss (setq i (rem (1+ i) l))))) '(4 3))
              )
              (redraw e 4)
              e
       )
     )
   )
 )

 (redraw)

 (if (and (AT:DrawX (setq p1 (getpoint "\nSpecify first point on curve: ")) 3)
          (or (setq ent (AT:CycleThroughSS
                          (ssget "_C"
                                 (list (car p1) (cadr p1))
                                 (list (car p1) (cadr p1))
                                 '((0 . "ARC,CIRCLE,ELLIPSE,LINE,*POLYLINE,SPLINE"))
                          )
                        )
              )
              (progn (alert "Point must be on curve!") (redraw))
          )
          (progn (redraw ent 3) T)
          (AT:DrawX (setq p2 (getpoint p1 "\nSpecify next point on curve: ")) 3)
          (or (and (ssget "_C"
                          (list (car p2) (cadr p2))
                          (list (car p2) (cadr p2))
                          '((0 . "ARC,CIRCLE,ELLIPSE,LINE,*POLYLINE,SPLINE"))
                   )
                   (setq d1 (vlax-curve-getDistAtPoint ent (trans p1 1 0)))
                   (setq d2 (vlax-curve-getDistAtPoint ent (trans p2 1 0)))
              )
              (progn (alert "Points must be on curve!") (redraw))
          )
     )
   ((lambda (dist / div)
      (while (< dist (- (cadr dlst) (setq div (/ (cadr dlst) 100.))))
        (grdraw (trans (vlax-curve-getPointAtDist ent dist) 0 1)
                (trans (vlax-curve-getPointAtDist ent (setq dist (+ div dist))) 0 1)
                1
        )
      )
      (princ)
      (alert (strcat "Distance between points on curve: " (rtos (abs (- d1 d2)))))
    )
     (car (setq dlst (vl-sort (list d1 d2) (function <))))
   )
 )
 (and ent (redraw ent 4))
 (princ)
)

 

For open polylines works fine.

 

When i have a close polyline give me one direction results. I try to Reverse the polyline but gives me the same results. Can someone convert it

 

 

1) Open or Close polyline [O/C]

 

if it is open is ok

 

2) for Close polyline ask

 

CW or CCW

 

Something like this. Look the attach photos and you will understand

 

Thanks

[marko_ribar]

I would use plav.lsp to add start-end vetices on polyline and then use plpath.lsp to create new polyline between these 2 points - both options are available [TOP/BOTTOM] - [CW/CCW]... Then I would just get length of new polyline by LIST command, or for more precise use (vl-load-com); (rtos (vla-get-length (vlax-ename->vla-object (car (entsel)))) 2 50) and pick newly created polyline...

 

For pline tools by M.R. (plpath.lsp+plintav.lsp+plav.lsp+pldv.lsp) check this link :

http://www.cadtutor.net/forum/showthread.php?67924-Draw-polyline-along-with-2-or-more-adjacent-closed-polylines/page3&highlight=plpath&p=#25

 

M.R.

[Snownut]

Search for a reverse polyline direction function, I seem to recall seeing one in the past couple of weeks.

[Guest]

Search for a reverse polyline direction function, I seem to recall seeing one in the past couple of weeks.

Autocad have comand to Reverse direction but the lisp give the same results.Understand a close polyline as open and measure the distanse with direction from the first point to last.

Can anyone fix it ?

Thanks