colo-grp.mkiv / last modification: 2019-12-06 19:53
%D \module
%D   [       file=colo-grp,
%D        version=2011.12.27, % moved from colo-ini
%D          title=\CONTEXT\ Color Macros,
%D       subtitle=Groups,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

%D Regular colors and palets are used most, contrary to groups
%D which is why we define their support in a separate module.

\writestatus{loading}{ConTeXt Color Macros / Groups}

\unprotect

%D \macros
%D   {definecolorgroup}
%D
%D The naming of the colors in this palet suggests some
%D ordening, which in turn is suported by color grouping.
%D
%D \starttyping
%D \definecolorgroup
%D   [red]
%D   [1.00:0.90:0.90,
%D    1.00:0.80:0.80,
%D    1.00:0.70:0.70,
%D    1.00:0.55:0.55,
%D    1.00:0.40:0.40,
%D    1.00:0.25:0.25,
%D    1.00:0.15:0.15,
%D    0.90:0.00:0.00]
%D \stoptyping
%D
%D In such a color group colors are numbered from~$1$ to~$n$.
%D
%D \showsetup{definecolorgroup}
%D
%D This kind of specification is not only more compact than
%D defining each color separate, it also loads faster and takes
%D less bytes.

\installcorenamespace{colorgroup}
\installcorenamespace{colorgroupsetter}

\newcount\c_colo_groups_n % scratch counter

\unexpanded\def\definecolorgroup % sort of obsolete, just use palets directly
  {\dotripleempty\colo_groups_define}

\def\colo_groups_define
  {\ifthirdargument
     \expandafter\colo_groups_define_normal
   \else
     \expandafter\colo_groups_define_checked
   \fi}

\def\colo_groups_define_normal[#1][#2][#3]%
  {\c_colo_groups_n\zerocount
   \processcommalist[#3]{\colo_groups_define_entry{#1}{#2}}}

\def\colo_groups_define_checked[#1][#2][#3]%
  {\doifelseinstring{:}{#2}
     {\colo_groups_define_normal[#1][\v!rgb][#2]}
     {\doloop % inherited
        {\ifcsname\??colorgroup#2:\recurselevel\endcsname
           \setevalue{\??colorgroup#1:\recurselevel}{\csname\??colorgroup#2:\recurselevel\endcsname}%
         \else
           \exitloop
         \fi}}}

\def\colo_groups_define_entry#1#2#3% name mode specification
  {\advance\c_colo_groups_n\plusone
   \csname\??colorgroupsetter\ifcsname\??colorgroupsetter#2\endcsname#2\else\s!rgb\fi\endcsname[#1:\the\c_colo_groups_n][#3:0:0:0:0]}

\setvalue{\??colorgroupsetter\s!gray}[#1][#2:#3]{\definecolor[#1][s=#2]}
\setvalue{\??colorgroupsetter\s!rgb }[#1][#2:#3:#4:#5]{\definecolor[#1][r=#2,g=#3,b=#4]}
\setvalue{\??colorgroupsetter\s!cmyk}[#1][#2:#3:#4:#5:#6]{\definecolor[#1][c=#2,m=#3=,y=#4,k=#5]}
\setvalue{\??colorgroupsetter\s!spot}[#1][#2:#3:#4]{\definespotcolor[#1][#2][p=#3]}

%D \macros
%D   {showcolorgroup}
%D
%D We can show the group by:
%D
%D \startbuffer
%D \showcolorgroup [blue] [horizontal,name,number,value]
%D \stopbuffer
%D
%D \typebuffer
%D
%D or in color:
%D
%D \startlinecorrection
%D \getbuffer
%D \stoplinecorrection
%D
%D which uses:
%D
%D \showsetup{showcolorgroup}

\fetchruntimecommand \showcolorgroup \f!colo_run

%D There are ten predefined color groups, like
%D \color[green]{\em groen}, \color[red]{\em rood},
%D \color[blue]{\em blauw}, \color[cyan]{\em cyaan},
%D \color[magenta]{\em magenta} and \color[yellow]{\em geel}.
%D
%D \startlinecorrection
%D \hbox to \hsize
%D   {\hss
%D    \showcolorgroup [red]    [vertical,name,number]\hss
%D    \showcolorgroup [green]  [vertical,name]\hss
%D    \showcolorgroup [blue]   [vertical,name]\hss
%D    \showcolorgroup [cyan]   [vertical,name]\hss
%D    \showcolorgroup [magenta][vertical,name]\hss
%D    \showcolorgroup [yellow] [vertical,name]\hss}
%D \stoplinecorrection
%D
%D These groups are used to define palets {\em alfa} upto {\em
%D zeta}. As long as we don't use colors from the same row, we
%D get ourselves distinctive palets. By activating such a palet
%D one gains access to its members {\em top} to {\em charm} (of
%D course one should use more suitable names than these).
%D
%D \startlinecorrection
%D \hbox to \hsize
%D   {\showpalet [alfa]    [vertical,name,number]\hss
%D    \showpalet [beta]    [vertical,name]\hss
%D    \showpalet [gamma]   [vertical,name]\hss
%D    \showpalet [delta]   [vertical,name]\hss
%D    \showpalet [epsilon] [vertical,name]\hss
%D    \showpalet [zeta]    [vertical,name]}
%D \stoplinecorrection
%D
%D By using the keyword \type {value} the individual color
%D components are shown too. When printed in color, these
%D showcases show both the colors and the gray value.

%D \macros
%D   {comparecolorgroup}
%D
%D The similar command:
%D
%D \startbuffer
%D \comparecolorgroup [blue]
%D \stopbuffer
%D
%D \typebuffer
%D
%D shows color groups:
%D
%D \startlinecorrection
%D \getbuffer
%D \stoplinecorrection
%D
%D this commands are defined as:
%D
%D \showsetup{comparecolorgroup}

\fetchruntimecommand \comparecolorgroup \f!colo_run

\protect \endinput