Re: Deprecate fltk graphics toolkit?

[John W. Eaton]

On 11/08/2017 12:50 PM, Daniel J Sebald wrote:

> I think the issue there is that Qt graphics has to be run in the main 
> thread.  So the --no-gui option (different from octave-cli) is a means 
> to get Qt graphics support in the main thread.

Qt graphics needs the Qt event loop.  The original QtHandles code 
managed this somehow, because it was implemented as an add-on to Octave 
before Octave had a GUI based on Qt.  So it must be possible to use a 
Qt-based graphics widget from Octave that does not have a GUI running 
initially.

> But you are right. 
> Perhaps the code could be configured so that compiling the octave-cli 
> version puts everything in a single thread.  Then there'd be no need for 
> the --no-gui option anymore.

I think we'd still want a --no-gui option to avoid starting the GUI.

Some people will still want a minimal version of Octave that doesn't 
directly link to Qt libraries.  And it would be nice to be able to start 
and stop the GUI from the command line, same as Matlab can do.  If we 
could do that (dynamically load the GUI instead of linking it directly 
to the main program), then we wouldn't need octave-cli.

jwe