lisp Select polylines between two selected blocks.

[srikanth_0126]

Hi,

i have multiple polylines in a series and block are placed on them. 

i want to select the polylines between two selected blocks.

sample file is attached.

Thanks,

Srikanth

select_between _two_blocks_sample.dwg

Edited June 25 by srikanth_0126

[EnM4st3r]

I first thought to go like this but then i saw that there are multiple polylines between the blocks.
This works only if there is only one Polyline inbetween.
 

; testing to select objects that touch each of the selected blocks
(defun c:selectTest123 (/ ss i bbx ents)
  (setq ss (ssget '((0 . "INSERT"))))
  (setq i 0)
  (while (< i (sslength ss))
    (setq bbx (LM:blockboundingbox (vlax-ename->vla-object (ssname ss i)))) ; get the blocks boundingbox
    (setq ents
      (cons
        (LM:ss->ent ; selectionset to list
          (ssget "_C" 
              (trans (car   bbx) 0 1) 
              (trans (caddr bbx) 0 1)
              '((0 . "LWPOLYLINE")); <----------- ssget filter
          )
        )
        ents
      )
    )
    (setq i (1+ i))
  )
  (setq ss (ssadd))
  (setq ents (LM:ListsIntersection ents))
  (if ents (sssetfirst nil (apply '(lambda (e) (ssadd e ss)) ents)))
)

Used many functions of Lee Mac, the ones used are in the file attached

used LM subfunctions.lsp

Edited June 25 by EnM4st3r

[BIGAL]

If  blocks are near a vertice or on a vertice helps, noticed block insertion point is not on a vertice in sample dwg. It may be feasible to get segments of a pline so between blk1 - blk2 is segments 5,6 & 7. Copy the pline you now have vertice points trim outside of the 2 block points, you now have a result a new pline, what now ?  But that's about where I stop. I worry about the inaccuracies of the blocks not being on a vertice.  Maybe provide a new sample dwg.

[srikanth_0126]

Hi @BIGAL, blocks are placed between two parallel lines. other line is not in given sample file. i use the selection as for input another lisp to create a length of selected polylines. it maybe possible to use bounding box overlap method. right now i'm using fastsel and chainselection by @Lee Mac. but, chainslection is selecting everything it touches and fastsel doesn't have any control. what i'm assuming  is with chainselection extending selection until it overlaps with a block. 

Edited June 26 by srikanth_0126

[srikanth_0126]

HI, @BIGAL i got this from this thread and its creates a new path between two and creates a new using traced polylines. i want select the traced polylines. is that possible with this code?