hyperref update (19dec09)

git-svn-id: svn://tug.org/texlive/trunk@16451 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 40 insertions, 0 deletions

diff --git a/Master/texmf-dist/doc/latex/hyperref/README b/Master/texmf-dist/doc/latex/hyperref/README
index bb594ecaf1a..69de8de9969 100644
--- a/Master/texmf-dist/doc/latex/hyperref/README
+++ b/Master/texmf-dist/doc/latex/hyperref/README
@@ -1097,6 +1097,46 @@ vietnam
   \usepackage{vietnam}
   \usepackage{hyperref}
 
+XeTeX
+-----
+  Default for the encoding of bookmarks is `pdfencoding=auto'.
+  That means the strings are always treated as unicode strings.
+  Only if the string restricts to the printable ASCII set,
+  it is written as ASCII string. The reason is that the
+  \special does not support PDFDocEncoding.
+
+  XeTeX uses the program xdvipdfmx for PDF output generation.
+  This program behaves a little different from dvipdfm, because
+  of the supported Unicode characters. Strings for bookmarks
+  or information entries can be output directly. The
+  big chars (char code > 255) are written in UTF-8 and
+  xdvipdfmx tries to convert them to UTF-16BE. However
+  hyperref already provides PDF strings encoded in UTF-16BE,
+  thus the result is a warning
+    "Failed to convert input string to UTF16..."
+  The best way would be, if xdvipdfm could detect the
+  byte order marker (\376\377) and skips the conversion
+  if that marker is present.
+    For the time being I added the following to hyperref,
+  when option `pdfencoding=auto' is set (default for XeTeX):
+  The string is converted back to big characters thus that the
+  string is written as UTF-8. But I am very unhappy with this
+  solution. Main disadvantage:
+  Two versions of \pdfstringdef are needed:
+  a) The string is converted back to big characters for
+     the "tainted keys" of xdvipdfmx (spc_pdfm.c: default_taintkeys).
+     The subset hyperref uses is /Title, /Author, /Subject,
+     /Keywords, /Creator, /Producer, /T. Any changes of this
+     set in xdvipdfmx cannot be detected by hyperref.
+  b) Without conversion for the other strings , providing UTF16be
+     directly. Examples: Prefix of page labels, some elements
+     of formulars.
+  Thus *each* application that uses \pdfstringdef now must
+  check, if it defines a string for some of the tained keys.
+  If yes, then the call of \pdfstringdef should be preceded
+  by "\csname HyPsd@XeTeXBigCharstrue\endcsname".
+  Example: package bookmark.
+
 
 7 LIMITATIONS
 =============