Re: wait_for_file ??

[Shai Ayal]

On Thu, Sep 9, 2010 at 9:07 AM, Shai Ayal <address@hidden> wrote:
> On Thu, Sep 9, 2010 at 6:33 AM, Michael D Godfrey
> <address@hidden> wrote:
>> On 09/08/2010 06:26 PM, Ben Abbott wrote:
>>
>> I think jwe's suggestion of drawing to a piped gs rather than to a
>>> file is the way to go. I'll try to implement the gl2ps part.
>>>
>>> Shai
>>
>> For gnuplot backend, the gnuplot eps file can be save to a tmp-file which
>> can then be converted via the pipe.
>>
>> However, for the opengl backends, the pipe approach will limit the formats
>> to those available from gl2ps and those available from gs (pdf, ps, ps2, and
>> many the bitmaps and printer languages). Am I correct?
>>
>> Output formatted as dxf, emf, fig, hpgl, ai, pstex, mf, etc (all formats
>> derived using pstoedit and fig2dev will no longer be available for opengl
>> backends? .... If so I think it best to avoid using pstoedit, fig2dev, and
>> epstool.
>>
>> Should the "-tight" option will need to go as well?
>>
>> As my questions indicate, I'm a bit cloudy on the implications. I'll be
>> studying this approach for a while and plan to wait on Shai before
>> contributing any significant changes.
>>
>> Ben
>>
>>
>>
>> This sounded good to me at first, but now I do not see how it is going to
>> work.
>> There must be something that ensures that routine glps_renderer::draw in
>> gl2ps-renderer.cc
>> really gets run when the code in __fltk_print__.m needs it.
>>
>> I hope Shai and Ben have this figured out.
>>
>> Michael
>
> I think using a pipe will not make the render code run when we need
> it, but at least it will make sure that gs is only called when the
> data to convert is ready.
>
> Shai
>

OK, I pushed the relevant changes to make fltk print to an fid
**warning** this breaks current fltk printing!
http://hg.savannah.gnu.org/hgweb/octave/rev/2786e3b7072e

to use, pass the fid as a string to drawnow:
e.g. to keep current functionality, use
fid = fopen ("test.eps","wb");
drawnow ("eps" , sprintf ("%d" , fid));

and to pipe it into another program, use popen:
fid = popen ("cat >  test.eps" , "w")
drawnow ("eps" , sprintf ("%d" , fid));

Shai