1 files changed, 32 insertions, 0 deletions
diff --git a/tex/context/base/attr-lay.mkiv b/tex/context/base/attr-lay.mkiv
new file mode 100644
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+++ b/tex/context/base/attr-lay.mkiv
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+%D \module
+%D   [       file=attr-lay,
+%D        version=2007.06.06,
+%D          title=\CONTEXT\ Attribute Macros,
+%D       subtitle=Viewerlayers,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright=PRAGMA-ADE]
+%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 Attribute Macros / Viewerlayers}
+
+\unprotect
+
+\registerctxluafile{attr-lay}{1.001}
+
+% needs to work over stopitemize grouping etc
+
+\def\registerviewerlayer#1#2% global !
+  {\setxvalue{(vl:#1)}{\global\attribute\viewerlayerattribute\ctxlua{tex.write(attributes.viewerlayers.register('#2'))} }}
+
+\setevalue{(vl:)}{\global\attribute\viewerlayerattribute\attributeunsetvalue}
+
+\def\dotriggerviewerlayer % move to lua
+  {\ctxlua{attributes.viewerlayers.enable()}%
+   \gdef\dotriggerviewerlayer##1{\csname(vl:##1)\endcsname}%
+   \dotriggerviewerlayer}
+
+\protect \endinput