Re: fltk printing

[Shai Ayal]

On Sun, Aug 8, 2010 at 4:40 AM, Ben Abbott <address@hidden> wrote:
> On Aug 7, 2010, at 8:16 PM, Ben Abbott wrote:
>
>> On Aug 7, 2010, at 8:00 PM, Dmitri A. Sergatskov wrote:
>>
>>> On Sat, Aug 7, 2010 at 6:37 PM, Michael D Godfrey
>>> <address@hidden> wrote:
>>>
>>>> It may be good to look at the drawnow code.
>>>>
>>>
>>> Here is some interesting test:
>>>
>>> # drawnowt.m
>>> backend("fltk");
>>> plot(1:2);
>>> drawnow("eps","junk111.eps");
>>>
>>> running
>>> octave < drawnowt.m
>>>
>>> results in:
>>>
>>> warning: implicit conversion from matrix to sq_string
>>> error: fltk_backend: could not recognize fltk index
>>> error: called from:
>>> error:   /home/dima/src/octave/scripts/miscellaneous/delete.m at line
>>> 48, column 1
>>> error:   /home/dima/src/octave/scripts/plot/closereq.m at line 37, column 7
>>> error:   /home/dima/src/octave/scripts/plot/close.m at line 63, column 5
>>> error:   /home/dima/src/octave/scripts/plot/close.m at line 77, column 1
>>> error:   /home/dima/src/octave/scripts/plot/close.m at line 57, column 5
>>> error:   /home/dima/src/octave/scripts/plot/__go_close_all__.m at line
>>> 27, column 3
>>>
>>> If I add at the end of the test file "pause(0)" it finishes correctly.
>>> That suggests me that drawnow spawns some  asynchronous processes.
>>>
>>>> Michael
>>>>
>>>>
>>>
>>> Sincerely,
>>>
>>> Dmitri.
>>> --
>>
>> Very strange ... The error doesn't give any indication of your test file, 
>> drawnowt.m.
>>
>> I can'f find any instance where __go_close_all__ is called in the sources.
>>
>> I tried you example on MacOS X, and as expected, no error.
>>
>> Ben
>
> sigh : -( ... my bad. __go_close_all__ can be called by drawnow() in 
> graphics.cc (I had misplaced a trust in MacOS X's finder).
>
> >From graphics .cc ...
>
> 5775 DEFUN (drawnow, args, ,
> 5776    "-*- texinfo -*-\n\
> 5777 @deftypefn  {Built-in Function} {} drawnow ()\n\
> 5778 @deftypefnx {Built-in Function} {} drawnow (\"expose\")\n\
> 5779 @deftypefnx {Built-in Function} {} drawnow (@var{term}, @var{file}, 
> @var{mono}, @var{debug_file})\n\
> 5780 Update figure windows and their children.  The event queue is flushed 
> and\n\
> 5781 any callbacks generated are executed.  With the optional argument\n\
> 5782 @code{\"expose\"}, only graphic objects are updated and no other events 
> or\n\
> 5783 callbacks are processed.\n\
> 5784 The third calling form of @code{drawnow} is for debugging and is\n\
> 5785 undocumented.\n\
> 5786 @end deftypefn")
> 5787 {
> 5788   static int drawnow_executing = 0;
> 5789   static bool __go_close_all_registered__ = false;
> 5790
> 5791   octave_value retval;
> 5792
> 5793   gh_manager::lock ();
> 5794
> 5795   unwind_protect frame;
> 5796   frame.protect_var (Vdrawnow_requested, false);
> 5797
> 5798   frame.protect_var (drawnow_executing);
> 5799
> 5800   if (++drawnow_executing <= 1)
> 5801     {
> 5802       if (! __go_close_all_registered__)
> 5803         {
> 5804           octave_add_atexit_function ("__go_close_all__");
> 5805
> 5806           __go_close_all_registered__ = true;
> 5807         }
>
> The function __go_close_all__ is trivial
>
>        function __go_close_all__ ()
>          close ("all", "hidden");
>        endfunction
>
> As a simple check, I added `disp ("__go_close_all__")' to the end of 
> __go_close_all__.m
>
> When I try ...
>
>        plot (1:10)
>        print test.pdf
>
> ... there is no indication that __go_close_all__ is called.
>
> My understanding is that the function octave_add_atexit_function, registers 
> "__go_close_all__" to be called when Octave exits. Additional functions may 
> be registered using `atexit ("foobar")' from the command line. I created a 
> function ...
>
>        function foobar ()
>          disp ("Bye World")
>          pause ()
>        endfunction
>
> .... then entered the command `atexit ("foobar")'. When I exit octave I get 
> "__go_close_all__", and "Bye World", with the pause.
>
> When I use the print function ...
>
>        close all
>        backend fltk
>        plot (1:10)
>        print test.pdf
>
> ... I get neither "__go_close_all__" or "Bye World" (I do get a correct 
> test.pdf).
>
> Dimitri / Michael,
>
> If you add `'disp("__go_close_all__")'  to __go_close_all__, create the my 
> foobar.m function add type `atexit ("foobar")' at the command line, what 
> happens when you ...
>
>        close all
>        backend fltk
>        plot (1:10)
>        print test.pdf
>
> Ben

I'm sorry to stir up all of this work. If you just waited until I woke up ....

Anyway, this is totally the fltk_backend's fault.
fltk is very good -- it will not redraw if it doesn't really have to--
e.g. if the figure window is minimized, it will not redraw. I am not
100% sure how to force it to redraw. It's a long standing issue for
me. I'll ask on the fltk mailing list

Shai