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-rw-r--r--Master/texmf-dist/doc/latex/base/encguide.tex33
1 files changed, 16 insertions, 17 deletions
diff --git a/Master/texmf-dist/doc/latex/base/encguide.tex b/Master/texmf-dist/doc/latex/base/encguide.tex
index 3a59efa581b..cccec4eb896 100644
--- a/Master/texmf-dist/doc/latex/base/encguide.tex
+++ b/Master/texmf-dist/doc/latex/base/encguide.tex
@@ -1,6 +1,6 @@
% \iffalse meta-comment
%
-% Copyright 1993-2014
+% Copyright 1993-2016
% The LaTeX3 Project and any individual authors listed elsewhere
% in this file.
%
@@ -1185,33 +1185,32 @@ above, and \LaTeX\ needs to be aware of the encoding used for each
font.
Unicode aims to provide a single encoding that removes most of the
-need to switch encodings, apart from very specialist use for non
-standard characters. Rather than assign codes in the range 0--256 (hex
+need to switch encodings, apart from very specialist use for non-standard characters. Rather than assign codes in the range 0--256 (hex
FF) Unicode codes are in the range 0--1,114,111 (hex 10FFFF), although
not all slots are available for distinct characters for technical
reasons. Unicode offers the possibility to use a single input encoding
(usually UTF-8) for all documents and to use essentially the same
Unicode encoding for all fonts, so removing the need to switch
-encodings in different context.
+encodings in different contexts.
Omega was perhaps the first widely used \TeX\ extension that
supported Unicode. Currently the two actively supported systems that are
-present in most modern \TeX\ distributions are xe\TeX\ and lua\TeX.
+present in most modern \TeX\ distributions are Xe\TeX\ and Lua\TeX.
When used with these extended \TeX\ engines, \LaTeX's font system can
-refer to Unicode fonts (typically OpenType fonts installed system wide
-on your operating system rather than fonts specifically encoded for
-\TeX. Currently the usual method of accessing these fonts is through
-the contributed \Pkg{fontspec} package. this uses the two
-\emph{Experimental} encoding \Enc{EU1} (on xe\TeX) and \Enc{EU2} (on
-lua\TeX). Technically these two are the same encoding in terms of
+refer to Unicode fonts (typically OpenType fonts installed system-wide
+on your operating system rather than fonts specifically encoded/installed for
+\TeX). Currently the usual method of accessing these fonts is through
+the contributed \Pkg{fontspec} package. This uses the two
+\emph{Experimental} encodings \Enc{EU1} (on Xe\TeX) and \Enc{EU2} (on
+Lua\TeX). Technically these two are the same encoding in terms of
allocating characters to numbered positions, but two encodings have
been specified due to some internal differences in font handling in
the two extended \TeX\ engines. The exact rules for \LaTeX\ encodings
for Unicode engines have not yet been finalised, however it is
possible that a single unified format can be used and so a single
-standardised name such as \Enc{UC} may be used. However at the present
-time \Enc{EU1} and \Enc{EU2} should be used, although it is rare to
+standardised name such as \Enc{TU} may be used in the future.
+At the present time, however, \Enc{EU1} and \Enc{EU2} should be used, although it is rare to
need to specify these explicitly in a document as the \Pkg{fontspec}
package sets up the correct encoding based on the engine in use.
@@ -1221,18 +1220,18 @@ lowercase table (and hyphenation patterns) can not be restricted to
the values used for \Enc{T1} and do only refer to the first 256
characters.
-When the \LaTeX\ format is made \LaTeX sets up the lowercase table
-and classifies characters as letter or non letter based on \Enc{T1} if
+When the \LaTeX\ format is made \LaTeX\ sets up the lowercase table
+and classifies characters as letter- or non-letter-based on \Enc{T1} if
a classic \TeX\ or pdf\TeX\ is being used. If a Unicode based \TeX\ is
detected, the values are instead based on the classification and
lower-case mappings provided by the Unicode Character Database
\cite{ucd}. The relevant part of these tables are converted to \TeX\
syntax as \ttverb{ltunicode.ltx} as part of the \LaTeX\ distribution.
-Similarly in the default configuration files used by modern \TeX\
+Similarly in the default configuration files used by modern \TeX\
distribution, the hyphenation files for each supported language are
written in UTF-8 encoding, using Unicode code points for all letters,
-then if a classic \TeX system is detected, some additional macros are
+then if a classic \TeX\ system is detected, some additional macros are
loaded to convert these files to 256-character encodings where
possible, and assuming the \Enc{T1} lowercase table.