Tilemode reactor problem

Yaacov Lazar

I've been trying to get this reactor thingy to work in Bricscad V10.

It's supposed to set the "LTSCALE" variable to 10 in paperspace and to a stored value in modelspace.

It seems to be loaded, but nothing happens.

It seems to work okay in Autocad 2000.

(This is my first attempt at a reactor or anything else in Vlisp)

(vl-load-com)
(setq CommandEndedReactor_Space nil Reactor_Function_Space nil )

(defun Reactor_Function_Space ( Arg1 Arg2 / )
  (if (= (car Arg2 ) "-LAYOUT" )
    (cond
      ((= (getvar "TILEMODE" ) 1 ) 
    (setq @dwg (if @dwg @dwg 100))
       (setvar "LTSCALE" @dwg)
       (setvar "PSLTSCALE" 1)
       (setvar "REGENMODE" 0)
       (princ)
     )
      ((= (getvar "TILEMODE" ) 0 )   
       (setvar "LTSCALE" 10)
       (setvar "PSLTSCALE" 1)
       (setvar "REGENMODE" 1)
      )
    )
  )
)
(setq CommandEndedReactor_Space 
  (vlr-command-reactor nil '((:vlr-commandEnded . Reactor_Function_Space ))) 
)
(defun c:terminate_tlm()
  (vlr-remove CommandEndedReactor_Space )
  (setq CommandEndedReactor_Space nil Reactor_Function_Space nil )
)

Torsten Moses

Dear Yaacov, you are using a command reactor - and inside the callback, you check for -LAYOUT (as command name);
so far so good - but this can only work, if command -LAYOUT has been enterd - but there is no such command :-)
But even if -LAYOUT would exist, this reactor would not fire i.e. if the layout is changed by mouse, or by other code.

A better approach is to place a SYSVARCHANGED reactor :
(setq reactor (vlr-sysvar-reactor nil '((:vlr-sysVarChanged . callback))))

Thus, you can monitor layout and tilemode switches ...

But now for the problems ... there are bugs currently, in both Acad and Bricscad, regarding system variables fired as reactor :

- Acad does correctly fire TILEMODE changes - but not sends the reactor for CTAB;
  when switching from model to layout1, and back, then TILEMODE is fired;
  when switching from Layout1 to Layout2 (and back), no reactor for CTAB is sent;
  => in fact, I did not found a safe + stable case to recognise Layout1 -> Layout2 switch, based on reactors ... in Acad

- Bcad does correctly send CTAB always - but not always for TILEMODE :-(
  but at least, when checking for CTAB in reactor callback, you can additionally check for TILEMODE by /getvar "TILEMODE"),
  so you have a safe + stable way to recognise all layout switches

I will report the TILEMODE system variable problem to our internal task list.

I use such simple code to examine the behaviour :

(vl-load-com)   ;; never forget this ! in Bcad it is a NO-Operation, but nessecary for Acad !
(defun cb (arg1 arg2) (print "--- cb ---")(print arg1)(print arg2)(print "*********")(princ))
(setq xxx (vlr-sysvar-reactor nil '((:vlr-sysVarChanged . cb))))

I hope this code sample helps ?
Many greeitngs, Torsten

Yaacov Lazar

Great! I'll try it.

Undoubtedly I'll have more dumb questions as I mess with reactors.

I'm always impressed by the seriousness of the technical support and design people in bcad.
There's a lot of fascinating stuff "under the hood", and I'm always interested in hearing about it.

Torsten Moses

Of course, you are always welcome :-) With *any* kind of question ...