Topic: Layers frozen in viewports ...

[MP]

In the past, like AutoCAD versions < 2000, I relied on the fact that layers frozen in a viewport were embedded in the viewport's extended data, in dxf group 1003 ...

Code: [Select]

(
   (-1 . <Entity name: 7ef55eb8>)
   (0 . "VIEWPORT")

   ...

   (-3
      (
         "ACAD"
         (1000 . "MVIEW")
         (1002 . "{")

         ...

         (1002 . "{")  
         (1003 . "LAY1") ;; layers
         (1003 . "LAY2") ;; frozen
         (1003 . "LAY3") ;; in
         (1003 . "LAY4") ;; this
         (1003 . "LAY5") ;; viewport
         (1002 . "}")
         
         ...
         
         (1002 . "}")
      )
   )
)
Since 2000, the frozen layers also appear as enames in dxf group 331 ...

Code: [Select]

(
   (-1 . <Entity name: 7ef55eb8>)
   (0 . "VIEWPORT")

   ...

   (331 . <Entity name: 7ef55ec8>) <--+
   (331 . <Entity name: 7ef55ed8>)    |
   (331 . <Entity name: 7ef55ee8>)    |
   (331 . <Entity name: 7ef55ef8>)    |
   (331 . <Entity name: 7ef55f08>) <--+--+
                                      |  |
   ...                                |  |
                                      |  |
   (-3                                |  |
      (                               |  |
         "ACAD"                       |  |
         (1000 . "MVIEW")             |  |
         (1002 . "{")                 |  |
                                      |  |
         ...                          |  |
                                      |  |
         (1002 . "{")                 |  |
         (1003 . "LAY1") <------------+  |
         (1003 . "LAY2")                 |
         (1003 . "LAY3")                 |
         (1003 . "LAY4")                 |
         (1003 . "LAY5") <---------------+
         (1002 . "}")

         ...

         (1002 . "}")
      )
   )
)
As a result, one can yank out the frozen layer names by examining the 331 groups ...

Code: [Select]

(defun GetLayersFrozenInViewport ( viewportEname )
    (   (lambda ( data / pair data2 result )
            (while (setq pair (assoc 331 data))
                (if
                    (member
                       '(0 . "LAYER")
                        (setq data2
                            (entget
                                (setq ename
                                    (cdr pair)
                                )
                            )
                        )
                    )
                    (setq result
                        (cons
                            (cdr (assoc 2 data2))
                            result
                        )
                    )
                )
                (setq data
                    (cdr
                        (member pair data)
                    )
                )
            )
            result
        )
        (entget viewportEname)
    )
)
Can anyone see a flaw in this technique (as opposed to the examination of the 1003 group codes)?

Know a better way? Please share.

[CAB]

MP,
Here is a routine I started yesterday. Did not get far as play time is short
for me these next few weeks. It is VERY rough, but the forzen layers seems to work
well.

Code: [Select]

(defun c:get_frozen (/ ent)
  (setq ent (vp_sel))
  (setq vp_frz_lst (vpfrzlays ent))
  (princ)
)

(defun c:put_frozen (/ ent)
  (setq ent (car (entsel "\nselect a viewport to updte:")))
  ;;  not here yet.
)

;;=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=-=-=-=-=-=-=-=-=-=
;; CAB modified code from Jason Piercey
;; Argument: Ename, viewport ename
;; Return: list frozen layer name or nil
;;=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=-=-=-=-=-=-=-=-=-=
(defun vpfrzlays (ename) ; by Jason Piercey
  (mapcar '(lambda (y) (cdr (assoc 2 (entget y))))
          (massoc 341 (entget ename))
  )
)


(defun massoc (key alist / x nlist) ; by Jaysen Long
  (foreach x alist
    (if (eq key (car x))
      (setq nlist (cons (cdr x) nlist))
    )
  )
  (reverse nlist)
)
;;=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=-=-=-=-=-=-=-=-=-=

;;  CAB select VP routine
;;  will work on VP made from other entities
(defun vp_sel (/ vpflag sel-vport entvport vptest)
  (if (= (getvar "TileMode") 1) ; in model space
    ;;------------------------------------------------
    (progn
      (alert "****  You must be in Paper Space to run this routine.  ****")
    )
    ;;------------------------------------------------
    (progn ;else in a layout
      (if (/= (getvar "cvport") 1)
        (command "_pspace") ; close the view port
      )
      (setq vpflag (getvar "cvport")) ; get viewport #
      (while (= vpflag 1) ; No active viewport, Loop until one is picked
        (setq sel-vport (car (entsel "\nSelect view port: ")))
        (if (= sel-vport nil)
          (alert
            "You must select a viewport\r\n    --=<  Try again!  >=--"
          )
          (progn
            (setq entvport (entget sel-vport))
            (if (and ;; not all vp objects are LWPolylines
                     ;;(= (cdr (assoc 0 entvport)) "LWPOLYLINE")
                     (setq vptest (member '(102 . "{ACAD_REACTORS") entvport))
                     (setq vptest (member '(102 . "}") (reverse vptest)))
                     (assoc 330 vptest)
                )
              (setq entvport (entget (cdr (assoc 330 vptest))))
            )

            ;;  Make VP active
            (if (= (cdr (assoc 0 entvport)) "VIEWPORT")
              (progn
                (setq vpflag (cdr (assoc 69 entvport)))
            ;;    (command "mspace") ; activate the last vp active
            ;;    (setvar "cvport" vpflag) ; switch to this vp
              )    
            );  endif  viewport
          )
        ) ;  endif cond  sel-vport
      ) ;endwhile (= vpFlag 1)
    )
  )
  ;;  return the ename of vp or nil
  (cond (entvport (cdr(assoc -1 entvport))))
)

[MP]

Thank you CAB, I'll look at that.

Just a heads up, but I believe Jaysen Long wrote massoc. Credit is a good thing.

[CAB]

I may have jumped to conclusion as to the author.
link

[MP]

Jason wrote VpFrzLays; Jaysen wrote Massoc.

I was going to say Jason's doesn't work, but then I checked ... dumb stuff Autodesk ... AutoCAD 2002 uses dxf group 341, AutoCAD 2004 uses dxf group 331.

That's as brainiac as needing to check an instance of an xref to find the xref's path (if using the object model).

</rant>

[CAB]

You have quite a memory, I'm sure it serves you well.
Just envious.  
I updated the credits.

[MP]

Remind me what a memory is 'kay?



(Good on ya btw).

[MP]

Screw it, I'm reverting back to my old way (slight mod) as it works back several releases and performs well enough.

Code: [Select]

(defun GetLayersFrozenInViewport ( viewportEname )
    ;;  © 1999-2005 Michael Puckett
    (   (lambda ( data / pair result )
            (while (setq pair (assoc 1003 data))
                (setq
                    data (cdr (member pair data))
                    result (cons (cdr pair) result)
                )
            )
        )
        (cdadr
            (assoc -3
                (entget
                    viewportEname
                   '("acad")
                )
            )
        )
    )    
)

[Mark]

How the heck do you do that.

[MP]

Eh?

[Mark]

Your code, it's like reading a book from the middle out.

it inspires me!!

[CAB]

Neat-o  thanks for sharing.

[MP]

I don't know what to say besides thanks!

<Shrugging.mpg>

[MP]

Hey, thanks CAB.

[CAB]

MP
In an effort to understand the function I need some explanation of some of the parts.
First it appears as though you left out the MapCar. The parentheses are there.
Is it understood somehow?

Code: [Select]

(   (lambda ( data / pair result )
 ............... ^^^  Mapcar??
 
  Then the list used in the lambda is generated by this
 

Code: [Select]

      (cdadr
            (assoc -3
                (entget  
                    viewportEname
                   '("acad")
                )
            )
        )

Second question, Why is this required

Code: [Select]

'("acad")
and what does it do?

PS I like the new emoticons Mark.