Octave Graphics, XML and GUI's : Beginning (yet another... )

Im reposting some stuff from the June, 2007 Octave-Maintainers mailing list here,

HOWTO add a new graphics property

Shai Ayal shaiay at gmail.com
Sat Jun 16 22:41:48 CDT 2007

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Hi all,

I wrote this up just to have some simple guide with all the necessary
steps on how to add a new graphics property. Please have a look and
correct it if necessary. Hopefully when finalized this howto will
enable more people to contribute code.

Shai

how to add property pppp of type tttt to axes:
all functions mentioned below are in src/graphics.cc and src/graphics.h

in axes_properties class definition, add:
OCTAVE_GRAPHICS_PROPERTY (tttt, pppp);

axes::axes_properties::axes_properties
add code to initialize

axes::axes_properties::set
add code to set ppp from an octave_value

axes::axes_properties::set_defaults
add code to set the default value

axes::axes_properties::get (void) const
add code to return as a cell

axes::axes_properties::get (const property_name& name) const
add code to return as an octave_value

property_list::pval_map_type axes::axes_properties::factory_defaults
add the factory default vlaue for pppp

if the property is a child object, also modify

void axes::axes_properties::delete_children
void axes::axes_properties::remove_child

Also, I noticed this last month and a littler earlier to that, many new projects on Octave, including

1. Qt-Octave, developed by from Spain
   
2. Octave-XML, developed by Thomas Geiger, from Austria?.
   

Also people start talking about the GUI frontier for Octave, and
John Swensen explains how he runs Octave interpreter with the Octave GUI properly. I wonder if writing an evaluating parse tree is a solution.

Nice to see the ideas flowing, and what makes Octave the really the diverse community on a shared platform it is. Being, Indian, I can appreciate the micro-worlds in macro-world.

Cheers,
Muthu