Re: problem with "set x11 {size WW,HH} {position XX,YY}"

[Ethan M. <merritt@u.washington.edu>]

On Friday 06 February 2009 09:38:10 Petr Mikulik wrote:
> > https://sourceforge.net/tracker/index.php?func=detail&aid=2570385&group_id=2055&atid=302055
> > [ 2570385 ] GPVAL_X11_WINDOWID
> >
> > > > 3. New global variable current_x11_windowid should be placed in an .h + .c 
> > > >    file. Which one?
> > > 
> > > > That will probably not work.  There can be multiple x11 windows open at 
> > > > the same time, so there is no "current" one.  Since you can associate a 
> > > > window number with each one, however, we might be able to do:
> > > >       set term x11 5
> > > >       print TERM_X11_WINDOW_5_ID 
> > > 
> > > The current one is the current active one. It is the last one from "set term 
> > > x11". The value of GPVAL_TERM_WINDOWID is to be used by a front-end (such as 
> > > Octave) using gnuplot for drawings; thus, it can fetch the Window ID just 
> > > after the plot command.
> > 
> > But "set term x11 5" will not necessarily open a new window; it will re-use
> > the old window #5 if there is one.  So it will not necessarily trigger a
> > window creation event, and thus would not automatically update your proposed
> > *_CURRENT_* variable.  I suppose the terminal driver could maintain a list
> > of previously-created window ids.
> 
> It does update the GPVAL_TERM_WINDOWID variable, please try the proposed 
> patch.

The intent is to update GPVAL_TERM_WINDOWID when the main program receives a
"new window" event from gnuplot_x11, right?  

I am trying to point out that not every command "set term x11 <num>" creates
a new window. If an old window is re-used, you won't receive this event and
therefore GPVAL_TERM_WINDOWID  will not be updated.

The patch currently has the event generated each time the buffered command
list is re-executed, which I think is not right.  Probably it should go in
pr_window(), immediately after the call to XCreateWindow().

-- 
Ethan A Merritt