Questions about "configure" and "native graphics"

[Julien Bect]

Dear all,

I have a couple of questions concerning the "configure" script... 
(source = mercurial tip)


If I configure with "./configure --without-fltk", I get "Build Octave 
GUI: yes" and the following warnings:

configure: WARNING: --without-fltk specified.  Native graphics will be 
disabled.
configure: WARNING: JAVA_HOME environment variable not initialized. 
Auto-detection will proceed but is unreliable.
configure: WARNING:
configure: WARNING: I didn't find the necessary libraries to compile native
configure: WARNING: graphics.  It isn't necessary to have native graphics,
configure: WARNING: but you will need to have gnuplot installed or you won't
configure: WARNING: be able to use any of Octave's plotting commands

What does "native graphics" mean ?

And why do I get a warning about not finding libraries for "native 
graphics", since "native graphics" have been disabled because of 
--without-fltk ?


Now, if I configure with "./configure --without-opengl" I get instead 
"Build Octave GUI: no" and

configure: WARNING: --without-opengl specified.  Native graphics will be 
disabled.
configure: WARNING: JAVA_HOME environment variable not initialized. 
Auto-detection will proceed but is unreliable.
configure: WARNING: --without-opengl was specified -- disabling GUI
configure: WARNING:
configure: WARNING: I didn't find the necessary libraries to compile native
configure: WARNING: graphics.  It isn't necessary to have native graphics,
configure: WARNING: but you will need to have gnuplot installed or you won't
configure: WARNING: be able to use any of Octave's plotting commands

Why does disabling OpenGL lead to "Build Octave GUI: no" ?

If I remember correctly, with Octave 8.2 I could disable OpenGL and 
still get a working GUI with gnuplot as a graphics toolkit.  Has this 
changed ?


@++
Julien