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+%D \module
+%D   [       file=colo-ext, % mostof thsi code used to be in colo-ini.tex
+%D        version=1997.04.01,
+%D          title=\CONTEXT\ Color Macros,
+%D       subtitle=Extras,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
+%C details.
+
+\writestatus{loading}{ConTeXt Color Macros / Extras}
+
+\unprotect
+
+%D \macros
+%D   {negatecolorcomponent, negativecolorbox}
+%D
+%D Sometimes, especially when we deal with typesetting
+%D devices, we want to reverse the color scheme. Instead of
+%D recalculating all those colors, we use a quick and dirty
+%D approach:
+%D
+%D \starttyping
+%D \negativecolorbox0
+%D \stoptyping
+%D
+%D will negate the colors in box zero.
+
+\def\negatecolorbox#1%
+  {\setbox#1\hbox
+     {\startnegativeproperty % might change
+      \startcolor[white]\vrule\!!height\ht#1\!!depth\dp#1\!!width\wd#1\stopcolor
+      \hskip-\wd#1%
+      \box#1%
+      \stopnegativeproperty}}
+
+%D There are in principle two ways to handle overprint: bound to colors
+%D or independent. For the moment we only support independent overprint
+%D handling. Here we deal with a per-document setting.
+
+\unexpanded\def\startcolorintent[#1]%
+  {\pushattribute\colorintentattribute
+   \dotriggercolorintent{#1}}
+
+\unexpanded\def\stopcolorintent
+  {\popattribute\colorintentattribute}
+
+\unexpanded\def\startoverprint{\startcolorintent[\v!overprint]}
+\unexpanded\def\stopoverprint {\stopcolorintent}
+
+\unexpanded\def\startknockout {\startcolorintent[\v!knockout ]}
+\unexpanded\def\stopknockout  {\stopcolorintent}
+
+\let\starttextcolorintent\relax
+\let\stoptextcolorintent \relax
+
+\setupcolors
+  [\c!overprint=\v!no]
+
+\appendtoks
+    \dosettextcolorintent
+\to \everysetupcolors
+
+\def\dosettextcolorintent
+  {\doifnot\@@clintent\v!none
+     {\xdef\starttextcolorintent{\noexpand\dotriggercolorintent{\@@clintent}}%
+      \glet\dosettextcolorintent\relax
+      \dotriggercolorintent\@@clintent}}
+
+\appendtoks \starttextcolorintent \to \everystarttextproperties
+\appendtoks \stoptextcolorintent  \to \everystoptextproperties
+
+\setupcolors[\c!intent=\v!none]
+
+% A goodie that replaces the startMPcolor hackery
+%
+% \definecolor[red-t]  [r=1,t=0.5,a=1]
+% \definecolor[green-t][g=1,t=0.5,a=1]
+% \defineintermediatecolor[mycolora][0.5,red,green]
+% \defineintermediatecolor[mycolorb][0.5,red-t,green-t]
+% \starttext
+%     test {\mycolora OEPS} test
+%     test {\mycolorb OEPS} test
+% \stoptext
+
+\unexpanded\def\defineintermediatecolor
+  {\dotripleempty\dodefineintermediatecolor}
+
+\def\dodefineintermediatecolor[#1][#2][#3]% \dotripleempty adds {} inside []
+  {\dododefineintermediatecolor[#1][#2][#3]}
+
+\def\dododefineintermediatecolor[#1][#2,#3,#4][#5]%
+  {\ifconditional\collectcolorsinlist\collectcolorinlist{#1}\fi
+   \ctxlua{colors.defineintermediatecolor("#1","#2",
+     \thecolorattribute{#3},\thecolorattribute{#4},
+     \thetransparencyattribute{#3},\thetransparencyattribute{#4},
+     "#5",false,\iffreezecolors true\else false\fi)}% not global
+   \dodefinecolorcommand\setvalue{#1}}
+
+\protect \endinput