GUI Qt figure window

[Daniel J Sebald]

Jacob,

I've managed to get the GUI working a little better and have tried 
plotting.  I notice that the plot is coming up as gnuplot X11 window.  I 
checked, and gnuplot now has a 'qt' terminal option that I've compiled. 
 Given that my system is all set up for Qt 4.7 now, all I had to do is

./configure --enable-qt

when building gnuplot.  I've run gnuplot, selected the qt terminal and 
run the demos.  Fonts and lines have good antialiasing properties.  The 
images scale pretty well.  Large meshes can be somewhat slow (but there 
might be a way to control Qt graphics speed according to the documentation).

The advantage with gnuplot qt terminal is that it has the same look and 
feel as your GUI-O.  The menubar might not contain what you'd like for 
the GUI-O plots, but there may be a way to work with that.  In gnuplot 
X11 term is a feature where one can specify an X11 window ID as a 
container.  That is, create some X11 app external to gnuplot to serve as 
a container, then set term x11 with an X window ID and gnuplot will plot 
into that window without all the added X stuff.  qt terminal appears to 
have a widget ID; my first guess would be that it is a similar sort of 
thing.  That means you should be able to create the layout for a GUI-O 
plot and pass in some widget for gnuplot to use.

Whatever platform GUI-O is built on will have the Qt environment all set 
to go so one can easily build gnuplot with qt support.

The only issue is being able to issue Octave a command to switch the 
terminal from x11/aqua/win to qt from the Octave command line.  I know 
that sort of thing is done internally in order to print, but external 
access may be hidden from the user now.  (I don't think we want Octave 
without GUI messing with Qt terminal.)

Dan