AutoLISP: Change Block Spacing in X-Direction (Row-Wise, No Y-Shift)

[Tamim]

I need help with adjusting the X-direction spacing of multiple blocks (row-wise) in AutoCAD. The Y-position should remain unchanged. For example, the current spacing between blocks is 27 ft, but once I select all the blocks and input a new value like 23 or 24, the blocks should automatically update to the new spacing as per my requirement.

BLK Sample.dwg

[Saxlle]

Hi @Tamim,

 

Try with this:

 

(prompt "\nTo run a LISP type: reara")
(princ)

(defun c:reara ( / old_osmode base_blk spacing ss base_blk_pt dist_blk_lst len i ins_pt dist n dist_n x_cord y_cord new_pt)

  (setq old_osmode (getvar 'osmode))
  (setvar 'osmode 0)
  
  (setq base_blk (car (entsel "\nPick the base block:\n"))
	spacing (getreal "\nEnter the spacing:\n")
	)

  (prompt "\nSelect BLOCK's:")
  
  (setq ss (ssget (list (cons 0 "INSERT")))
	base_blk_pt (cdr (assoc 10 (entget base_blk)))
	dist_blk_lst (list)
	)
  
  (if (ssmemb base_blk ss)
    (ssdel base_blk ss)
    )
  
  (setq len (sslength ss)
	i 0
	)
  
  (while (< i len)
    
    (setq ins_pt (cdr (assoc 10 (entget (ssname ss i))))
	  dist (distance base_blk_pt ins_pt)
	  dist_blk_lst (cons (list dist (ssname ss i)) dist_blk_lst)
	  i (1+ i)
	  )
    )
  
  (setq dist_blk_lst (vl-sort dist_blk_lst (function (lambda (x1 x2) (< (car x1) (car x2)))))
	n 0
	)
  
  (repeat (length dist_blk_lst)
    
    (setq dist_n (- (car (nth n dist_blk_lst)) spacing (* spacing n))
	  x_cord (- (cadr (assoc 10 (entget (cadr (nth n dist_blk_lst))))) dist_n)
	  y_cord (caddr (assoc 10 (entget (cadr (nth n dist_blk_lst)))))
	  new_pt (list x_cord y_cord)
	  )
    
    (command-s "_move" (cadr (nth n dist_blk_lst)) "" (cdr (assoc 10 (entget (cadr (nth n dist_blk_lst))))) new_pt)
    
    (setq n (1+ n))
    
    )

  (setvar 'osmode old_osmode)
  
  (prompt (strcat "\nThe " (itoa (length dist_blk_lst)) " are rearanged!"))
  
  (princ)
  
  )

 

See the following video how it works.

 

 

Best regards.

[Tamim]

6 minutes ago, Saxlle said:

Hi @Tamim,

 

Try with this:

 

(prompt "\nTo run a LISP type: reara")
(princ)

(defun c:reara ( / old_osmode base_blk spacing ss base_blk_pt dist_blk_lst len i ins_pt dist n dist_n x_cord y_cord new_pt)

  (setq old_osmode (getvar 'osmode))
  (setvar 'osmode 0)
  
  (setq base_blk (car (entsel "\nPick the base block:\n"))
	spacing (getreal "\nEnter the spacing:\n")
	)

  (prompt "\nSelect BLOCK's:")
  
  (setq ss (ssget (list (cons 0 "INSERT")))
	base_blk_pt (cdr (assoc 10 (entget base_blk)))
	dist_blk_lst (list)
	)
  
  (if (ssmemb base_blk ss)
    (ssdel base_blk ss)
    )
  
  (setq len (sslength ss)
	i 0
	)
  
  (while (< i len)
    
    (setq ins_pt (cdr (assoc 10 (entget (ssname ss i))))
	  dist (distance base_blk_pt ins_pt)
	  dist_blk_lst (cons (list dist (ssname ss i)) dist_blk_lst)
	  i (1+ i)
	  )
    )
  
  (setq dist_blk_lst (vl-sort dist_blk_lst (function (lambda (x1 x2) (< (car x1) (car x2)))))
	n 0
	)
  
  (repeat (length dist_blk_lst)
    
    (setq dist_n (- (car (nth n dist_blk_lst)) spacing (* spacing n))
	  x_cord (- (cadr (assoc 10 (entget (cadr (nth n dist_blk_lst))))) dist_n)
	  y_cord (caddr (assoc 10 (entget (cadr (nth n dist_blk_lst)))))
	  new_pt (list x_cord y_cord)
	  )
    
    (command-s "_move" (cadr (nth n dist_blk_lst)) "" (cdr (assoc 10 (entget (cadr (nth n dist_blk_lst))))) new_pt)
    
    (setq n (1+ n))
    
    )

  (setvar 'osmode old_osmode)
  
  (prompt (strcat "\nThe " (itoa (length dist_blk_lst)) " are rearanged!"))
  
  (princ)
  
  )

 

See the following video how it works.

 

 

Best regards.

Thanks for the prog. However, this only works for a single X row. I need to select both top and bottom rows (like Y1 and Y2), and show the result below the image.

[Saxlle]

Do it row by row, not selecting everything.

[Tamim]

3 hours ago, Saxlle said:

Do it row by row, not selecting everything.

understood, but i have more than 10000 numbers for each CAD file 

Edited September 11 by Tamim

[Saxlle]

Upload another example file to see what it looks like. But I'm afraid it can't be done easily, because you have to choose a reference point for the base block, and then rearrange the other blocks to be at equal distances. If you want to select "n" blocks, what can be a reference point from that selection set, which block? Also, they have different insertation points.

Edited September 11 by Saxlle

[BlackBox]

(vl-load-com)

(defun c:FOO (/ *error* acDoc ss pt y item data blocks)

  (defun *error* (msg)
    (if ss (vla-delete ss))
    (if acDoc (vla-endundomark acDoc))
    (cond ((not msg))                                                   ; Normal exit
          ((member msg '("Function cancelled" "quit / exit abort")))    ; <esc> or (quit)
          ((princ (strcat "\n** Error: " msg " ** ")))                  ; Fatal error, display it
    )
    (princ)
  )
    
  (if
    (and
      (ssget "_:L" '((0 . "INSERT")))
      (setq d (getreal "\nEnter Block distance: "))
    )
     (progn
       (vla-startundomark
         (setq acDoc (vla-get-activedocument (vlax-get-acad-object)))
       )
       (vlax-for x (setq ss (vla-get-activeselectionset acDoc))
         (setq pt (vlax-get x 'insertionpoint))
         (if (setq item (assoc (setq y (cadr pt)) data))
           (setq data
                  (subst (cons (car item) (append (cdr item) (list x))) item data)
           )
           (setq data (cons (cons y (list x)) data))
         )
       )
       (if data
         (foreach item data
           (setq blocks
                  (vl-sort
                    (cdr item)
                    (function
                      (lambda (a b)
                        (< (car (vlax-get a 'insertionpoint))
                           (car (vlax-get b 'insertionpoint))
                        )
                      )
                    )
                  )
           )
           (setq pt (vlax-get (car blocks) 'insertionpoint))
           (foreach block (cdr blocks)
             (vla-move
               block
               (vlax-3d-point (vlax-get block 'insertionpoint))
               (vlax-3d-point (setq pt (polar pt 0.0 d)))
             )
           )
         )
       )
     )
  )

  (*error* nil)
)

 

This works for each group of Blocks at a given Y level, based on the lowest X position in a given row as starting point.

 

Edited September 11 by BlackBox

[BlackBox]

On 9/11/2025 at 11:52 AM, BlackBox said:

(vl-load-com)

(defun c:FOO (/ *error* acDoc ss pt y item data blocks)

  (defun *error* (msg)
    (if ss (vla-delete ss))
    (if acDoc (vla-endundomark acDoc))
    (cond ((not msg))                                                   ; Normal exit
          ((member msg '("Function cancelled" "quit / exit abort")))    ; <esc> or (quit)
          ((princ (strcat "\n** Error: " msg " ** ")))                  ; Fatal error, display it
    )
    (princ)
  )
    
  (if
    (and
      (ssget "_:L" '((0 . "INSERT")))
      (setq d (getreal "\nEnter Block distance: "))
    )
     (progn
       (vla-startundomark
         (setq acDoc (vla-get-activedocument (vlax-get-acad-object)))
       )
       (vlax-for x (setq ss (vla-get-activeselectionset acDoc))
         (setq pt (vlax-get x 'insertionpoint))
         (if (setq item (assoc (setq y (cadr pt)) data))
           (setq data
                  (subst (cons (car item) (append (cdr item) (list x))) item data)
           )
           (setq data (cons (cons y (list x)) data))
         )
       )
       (if data
         (foreach item data
           (setq blocks
                  (vl-sort
                    (cdr item)
                    (function
                      (lambda (a b)
                        (< (car (vlax-get a 'insertionpoint))
                           (car (vlax-get b 'insertionpoint))
                        )
                      )
                    )
                  )
           )
           (setq pt (vlax-get (car blocks) 'insertionpoint))
           (foreach block (cdr blocks)
             (vla-move
               block
               (vlax-3d-point (vlax-get block 'insertionpoint))
               (vlax-3d-point (setq pt (polar pt 0.0 d)))
             )
           )
         )
       )
     )
  )

  (*error* nil)
)

 

This works for each group of Blocks at a given Y level, based on the lowest X position in a given row as starting point.

 

 

@Tamim Did this help?