gnuplot development

On Thursday 14 August 2008 07:09:05 Petr Mikulik wrote:
> There a patch "Tango color palette support" which adds the following "Tango 
> colornames" into the list of color names in gnuplot:
> 
> tango-butter-1 ... tango-butter-3
> tango-chameleon-1 ... tango-chameleon-3
> tango-orange-1 ...
> tango-sky-blue-1 ... 
> tango-sky-plum-1 ... 
> tango-chocolate-1 ... 3
> tango-scarlet-red-1 ... 3
> tango-aluminium-1 ... 6
> 
> The patch is here:
> 	https://bugzilla.redhat.com/show_bug.cgi?id=458525
> 
> Does it make sense to add more color names (see "show palette colornames")?

Rather than adding specifically this small set (or any other small set)
of color names, I think it would make more sense to add a general mechanism.

For example, all x11-based systems should have a file equivalent to
/usr/share/X11/rgb.txt, which contains entries of the form:
  250 235 215             antique white
  250 235 215             AntiqueWhite
  255 239 213             papaya whip
  255 239 213             PapayaWhip
  255 235 205             blanched almond
We could add a check for an environmental variable GNUPLOT_COLORNAMES,
default it to /usr/share/X11/rgb.txt, and write a corresponding parser routine.
Local customization is easy; just point GNUPLOT_COLORNAMES to a customized
file.


With specific regard to the Tango color scheme, I think the patch kind of misses
the point.  Tango is designed as a scheme for desktop icons and widgets.
At least under KDE you can set this at the level of the desktop manager, and
applications like gnuplot will inherit them.  I suspect other desktop systems
behave similarly.  If I pick the Tango scheme on my desktop, I get those
colors for foreground/background/icons/etc on my gnuplot x11 windows already.

Another point:  this is exactly the sort of customized user preference that
motivated patchset   #2004590    "mechanism to redefine base linetypes"
The user can select from the Tango colors (there really are not very many of
them) to set the default sequence of linetypes in ~/.gnuplot


-- 
Ethan A Merritt
Biomolecular Structure Center
University of Washington, Seattle 98195-7742

> > There a patch "Tango color palette support" which adds the following "Tango 
> > colornames" into the list of color names in gnuplot:
> >
> > The patch is here:
> > 	https://bugzilla.redhat.com/show_bug.cgi?id=458525
> > 
> > Does it make sense to add more color names (see "show palette colornames")?
> 
> Rather than adding specifically this small set (or any other small set)
> of color names, I think it would make more sense to add a general mechanism.
> 
> For example, all x11-based systems should have a file equivalent to
> /usr/share/X11/rgb.txt, which contains entries of the form:
>   250 235 215             antique white
>   250 235 215             AntiqueWhite
>   255 239 213             papaya whip
>   255 239 213             PapayaWhip
>   255 235 205             blanched almond
> We could add a check for an environmental variable GNUPLOT_COLORNAMES,
> default it to /usr/share/X11/rgb.txt, and write a corresponding parser routine.
> Local customization is easy; just point GNUPLOT_COLORNAMES to a customized
> file.

I think this would be handy as well:

	set palette colornames add "white" "#FFFFFF"
	set palette colornames add "white" "#FFFFFF" "black" "#FFFFFF"
	set palette colornames from "/usr/share/X11/rgb.txt"

It would overwrite and add new colours into the currently defined list of 
colours.

---
PM

On Thursday 14 August 2008 13:24:37 Petr Mikulik wrote:
> > > There a patch "Tango color palette support" which adds the following "Tango 
> > > colornames" into the list of color names in gnuplot:
> > >
> > > The patch is here:
> > > 	https://bugzilla.redhat.com/show_bug.cgi?id=458525
> > > 
> > > Does it make sense to add more color names (see "show palette colornames")?
> > 
> > Rather than adding specifically this small set (or any other small set)
> > of color names, I think it would make more sense to add a general mechanism.
> > 
> > For example, all x11-based systems should have a file equivalent to
> > /usr/share/X11/rgb.txt, which contains entries of the form:
> >   250 235 215             antique white
> >   250 235 215             AntiqueWhite
> >   255 239 213             papaya whip
> >   255 239 213             PapayaWhip
> >   255 235 205             blanched almond
> > We could add a check for an environmental variable GNUPLOT_COLORNAMES,
> > default it to /usr/share/X11/rgb.txt, and write a corresponding parser routine.
> > Local customization is easy; just point GNUPLOT_COLORNAMES to a customized
> > file.
> 
> I think this would be handy as well:
> 
> 	set palette colornames add "white" "#FFFFFF"
> 	set palette colornames add "white" "#FFFFFF" "black" "#FFFFFF"
> 	set palette colornames from "/usr/share/X11/rgb.txt"
> 
> It would overwrite and add new colours into the currently defined list of 
> colours.

I've just noticed that internal lists are kept in two places, which is
just asking for conflicts.

src/bitmap.c 
struct rgb web_color_rgbs[] =
{
    { 0xff, 0xff, 0xff },               /* background: white         */
    { 0x00, 0x00, 0x00 },               /*    borders: black         */
    ...  99 names total

src/tables.c
/* fixed RGB color names for 'set palette defined' */
const struct gen_table pm3d_color_names_tbl[] =
{
    /* black, white and gray/grey */
    { "white"           , 255*(1<<16) + 255*(1<<8) + 255 },
    { "black"           ,   0*(1<<16) +   0*(1<<8) +   0 },
    ...  81 names total


The first step should somehow consolidate these into a single list,
which could then be made extensible.


-- 
Ethan A Merritt