Re: graphics crossroads

[Shai Ayal]

We have a handle graphics RFC in wiki + skeleton implementation by Bill Denney. 
It's been idle for some time since no-one was willing to invest time. However, If a lot of work is going to be invested in octave graphics now because of new interests/problems  I suggest to follow up on this work, which is quite well thought out and should allow adding other plotting back-ends in the future.

Shai

On 11/17/06, Søren Hauberg < address@hidden> wrote:

John W. Eaton skrev:
> | One possibility would be to remove plotting support from octave. Then
> | have a package containing the current plotting functions, and another
> | package containing the development graphics object based system. That
> | way it would be easier to release 3.0 if the objects based system takes
> | time to develop.
> | (I'm not sure if this is a good idea, but I thought I'd mention it...)
>
> For minimum surprise, I think we would have to go back a few weeks on
> the plotting functions.  But then we would not have a reliable legend
> command or plotting on top of images in 3.0.
That would really be a shame, but I see where you're coming from. Could
we develop the objects based system without removing the current system?
Either as a package or just with prefixed function names.

> | It's fine with me if the __gnuplot_raw__ calls fails. But if we really
> | want people to stop using these commands it might be helpful to provide
> | some functions to write your data to a file that gnuplot can read.
>
> In the current CVS, I have
>
>   FILE = __gnuplot_save_data__ (VAL, NDIM, PARAMETRIC)
Perhaps that function should be renamed to gnuplot_save_data and when
people need more control of their plots then the highlevel system
allows, we could tell them to use that function?

I'm not really good with graphics (and I don't speak gnuplot), but I
guess I could lend a hand in the development of an objects based system.
So assuming all information about a plot has to be saved, what is all
information?

  * The type of the plot (2d, 3d, mesh, surface, etc.)
  * The data (x, y (and possibly z) values)
  * Style information (color, line thickness, etc.)
  * Figure number?
  * Some subplot things?

Also, what would be the target version of gnuplot? Can we assume 4.2?
Should we require 4.0? How about 3.2? (you get the idea...)

Søren