Re: list-colors-display: display all color names

["Eli Zaretskii" <eliz@gnu.org>]

> From: Juri Linkov <juri@jurta.org>
> Date: Wed, 05 Jan 2005 07:38:28 +0200
> Cc: eliz@gnu.org, emacs-devel@gnu.org
> 
> There is already such a function: `tty-color-approximate' (currently
> it works only for tty colors).

That's because for graphics displays, the same approximation is done
by the C function x_alloc_nearest_color_1.

> I don't know how it is useful from the user's POV.

`tty-color-approximate' is not a user-level function, in general.

> What I intended with adding #RRGGBB values was to make it
> easier for users getting somewhere a #RRGGBB value to see if there is
> a corresponding easily rememberable color name.

How did you think to do that?  I don't think there's a solution for
this problem, since the full set of colors known to the window system
is unknown to Emacs (the colors that are produced by
`list-colors-display' are taken from a partial list that might be only
a tiny fraction of the full list).

> Even better would be if the *Colors* buffer was sorted by RGB values.
> I don't suggest to do that by default, but different sorting order would
> be useful, e.g. by color name, by color intensity.  The latter is good
> for finding a darker or brighter color than a given color, but it is not
> so obvious since there are too many variants of projecting a color value
> from 3-D color space into a 1-D color list.  Perhaps the most useful is
> sorting by hue into a rainbow, and inside every hue sorting by value*saturation.

If we want to add something like that, I'd rather go for a
full-fledged color selection cube, where one can select a color by
moving the mouse pointer, similar to what some X applets let you do.