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+LaTeX support for texnansi encoding (LY1)
+===========================================
+
+Installing
+==========
+
+Ordinarily, you don't have to do anything, since this package is likely
+already present in your TeX distribution (TeX Live, MiKTeX).
+
+But if you're on your own, then just recursively copy the directories
+here to your texmf-local (or some) tree, preserving structure. Then add
+the map files *8y.map to your dvips setup and/or update the
+configuration of other DVI drivers correspondingly. You will have to
+adjust URW vs. Adobe names as needed. (In TeX Live, this is already
+done in dvips35.map, etc., in conjunction with updmap, and the *8y.map
+files here are not used.)
+
+Usage
+=====
+
+The font encoding `LY1` corresponds to the `texnansi` encoding
+originally used in the Y&Y TeX system. There is also an option to
+support the `ansinew` encoding that is the default encoding in
+Microsoft Windows.
+
+The main file is `ly1enc.def`. This contains the declaration of
+the encoding. To use `texnansi` encoded fonts within LaTeX,
+typically you just need to add the line
+
+
+ \usepackage[LY1]{fontenc}
+
+to your document preamble.
+
+An alternative to the above line is to use the `texnansi` package
+
+ \usepackage{texnansi}
+
+This will call the fontenc package, as above, to set up the LY1
+encoding but then make further changes to the uppercase and
+lowercase tables. Note that LaTeX does not need these changes to
+correctly uppercase text as its \MakeUppercase and \MakeLowercase
+commands only require the uppercase and lower case codes of the
+letters a-z.
+
+So for most purposes it is better to use the call to fontenc
+rather than use the `texnansi' package. Then, if you pass the
+file to a site using T1 (Cork) encoded fonts the line can more
+easily be changed to
+
+ \usepackage[T1]{fontenc}
+
+The texnansi package has a package option `ansinew` which
+modifies the LY1 encoding to refer to that MS Windows
+encoding. However you should only do this if your TeX system
+can not reencode fonts to support T1 or LY1. The `ansinew`
+treatment of the left quote ` as a grave accent makes it
+rather unsuitable for TeX use. It also lacks several useful
+glyphs. However if you need to, you can do:
+
+ \usepackage[ansinew]{texnansi}
+
+The other possible reason for using the `texnansi` package
+relates to the use of the lowercase table in the hyphenation
+algorithm. This is described below, but it is unfortunately
+of necessity rather technical, and you may want to stop
+reading at that point.
+
+LY1 matches OT1 well enough that you can usually use it in that role
+also. You can `\input` texnansi if you want this to work exactly even
+in plain TeX.
+
+Having declared the LY1 encoding to LaTeX, LaTeX will need to
+know the fonts that are available in this encoding. This
+distribution includes TeX metrics, font definition files and
+map files for the common "Standard PostScript" fonts.
+
+For each encoding LaTeX needs to know an `error font` which is
+its fall back in the case that the font substitution system
+can find nothing better to do. ly1enc.def specifies that the
+Error Font for LY1 is Adobe Times-Roman. Any PostScript
+interpreter must be able to provide Times-Roman, so it seems a
+good choice as the error font. Yet you may wish to change
+this for any reason; just edit the lines
+
+ \DeclareErrorFont{LY1}{ptm}{m}{n}{10}
+ \DeclareFontSubstitution{LY1}{ptm}{m}{n}
+
+at the top of ly1enc.def to refer to some other font set. For example
+if you have Y&Y TeX's "Lucida Bright" distribution you could change the
+two occurrences of `{ptm}` to `{hlh}` to make LaTeX fall back on Lucida
+Bright if all else fails. Please follow the LPPL and do not
+capriciously alter ly1enc.def in other ways.
+
+For more information on LY1 encoding and see Y&Y's WWW page:
+
+ <http://www.tug.org/yandy/usely1.htm>
+
+
+A Note on Lowercase Codes and Hyphenation Tables
+================================================
+
+The lowercase table is used by TeX's hyphenation algorithm, so
+in principle one would need to change the lowercase table to
+match the encoding used. However, it should not be changed
+mid paragraph as all words, whatever font encoding they are
+set in, are lowercased using the table current at the *end* of
+the paragraph before being checked for hyphenation. Because
+of these limitations in TeX's hyphenation algorithm, LaTeX
+does not support changing the lowercase table mid document, so
+if the `texnansi` package is used then the `texnansi`
+lowercase table will be used for all fonts (whether or not LY1
+encoded) and conversely if it is not used, the T1 table will
+be used, even for LY1 encoded fonts. The reason why this
+problem is not as serious as it may at first appear is that
+the majority of letters (as opposed to ligatures, and symbols)
+that occur in LY1 occur in the same place in T1.
+
+The only letters that might possibly appear in a hyphenation
+table that are in different positions in T1 and LY1 are:
+
+```
+\oe (low position OT1 high new)
+\ss (low position OT1 high new)
+\v{s}
+\v{z}
+\l
+\i OT1 (although *composites* such as \'\i are in T1 position
+ so this will only affect languages (Turkish?) that use
+ an unaccented \i)
+\"{y}
+```
+
+It should be noted that for those symbols that occur twice in
+LY1, the "high" copy is used if it coincides with the position
+used in T1 (as in the case of \ae, \o) otherwise the "low"
+copy will be used which will coincide with the OT1 position
+(\oe, \ss). (Unless the setup for ansinew is enabled in which
+case the high position is always used.)
+
+Fortunately most hyphenation files for Western European
+languages (I checked French, German and Danish) duplicate all
+the hyphenation patterns using these letters so that the
+tables work with both T1 and OT1 (and hence LY1) encoded
+fonts. However if you are using a language that makes use of
+say, \ss, but the hyphenation patterns just refer to \ss as
+^^ff then you will need to copy the hyphenation file and edit
+all occurrences of ^^ff to refer to the new position; either
+^^19 (for texnansi) or ^^df (for ansinew).
+
+The remaining letters that are in different positions, such as
+s caron, may be dealt with similarly, although they are mainly
+used in Eastern European languages. The LY1 encoding does not
+have as many glyphs for Eastern European languages as T1, so
+for those languages most likely this encoding is not suitable.
+(Of course TeX can produce all the accented letters required,
+but the hyphenation algorithm can not work with such
+constructed composites it can only work with composite letters
+that actually occur in the font.)
+
+It would be a good thing if hyphenation tables did not refer
+to any explicit character positions using the ^^ab notation,
+but rather always accessed characters by control sequences
+such as \ss. This would allow the remapping to be done via
+inputting a file such as ly1enc.def rather than by editing the
+hyphenation file. However currently most of the publicly
+available hyphenation tables unfortunately do "hard wire" the
+T1 character codes in this way.
+
+
+Copyright 1997 David Carlisle
+(Updated Feb. 2001 Walter Schmidt)
+(Updated Jun. 2010 Karl Berry)
+(Updated Oct. 2010 Karl Berry -- Times small caps faked as intended.)
+(Updated Jan. 2011 Karl Berry
+ -- missing map entries for ptmrr8ye and ptmr8yn.
+ -- irrelevant {phvl*,psyr,pzdr}.tfm removed.
+ -- relevant ptm{b,r}c8y.vf included, and corresponding ptm{b,r}c8y.tfm.
+ Thanks to Bruno Voisin for much research and debugging.
+)
+(Updated June 2022 David Carlisle )
+
+All the files in this directory may be redistributed and/or modified
+under the terms of the LaTeX Project Public License
+http://www.latex-project.org/lppl/
+either version 1 of the License, or (at your option) any later version.