Along
with
the [color values available for syntactic use in Tcl scripts],
several other facts about color might interest programmers.
This page aims to collect all this sort of information.
----
Okay, here's the standard (and rather reliably portable) 6x6x6 color cube.  This page has been
around forever:
   
   http://the-light.com/colclick.html
----



The source file which realizes the description which appears in the
hyperlink at the top of this page is xlib/xcolor.c.  X11 (Unix) systems
often have a `showrgb` command and/or .../lib/X11/rgb.txt
which give the same (?) data.  Programmatic access to the English-to-RGB-code map is available as
  winfo rgb . $color




----
[chooseColor] answers some questions on this subject.
----
The [W3C] maintains a list [http://www.w3.org/MarkUp/Guide/Style#colors]
of "Web-safe" colors.
----
xcolors is an interesting command under X11.

----
International Color Consortium maintains a page [http://www.color.org] which has information on ICC color profiles for computer color matching.

Mildly related to this is "[Selecting visually different RGB colors]".
----
'''Percent to color''': The following routine produces a color from an integer between 0 and 100, where 0 is red, 50 is yellow, and 100 is green (useful e.g. for painting progress bars):
 proc percent2rgb {n} {
    # map 0..100 to a red-yellow-green sequence
    set n     [expr {$n < 0? 0: $n > 100? 100: $n}]
    set red   [expr {$n > 75? 60 - ($n * 15 / 25) : 15}]
    set green [expr {$n < 50? $n * 15 / 50 : 15}]
    format    "#%01x%01x0" $red $green
 } ;# RS
----
"Color manipulation" [http://aspn.activestate.com/ASPN/Cookbook/Tcl/Recipe/133529] is the name of an ASPN recipe.
----
'''Random color:''' [EE] presented this simple beauty in the [Tcl chatroom] on 2002-12-18:
 proc randomColor {} {format #%06x [expr {int(rand() * 0xFFFFFF)}]}


----
[Tk syntax help] - [Arts and crafts of Tcl-Tk programming]