[This is ./doc/fonts/ibycus4/tex/README
 12 July, 1997.  [For some of the previous history see the 
	final notes on Ibycus 3, from May 30, 1966 in README.ibycus3]
	
		( THIS IS A TDS-CONFORMANT PACKAGE )

BE SURE THAT ibycus4.map HAS BEEN MADE ACCESSIBLE AS DESCRIBED BELOW

FOR INCOMPATIBILITIES WITH IBYCUS3, SEARCH FOR %%%%%%%%%%%% on page 3.

Like its predecessors, Ibycus4 is based on Silvio Levy's
realization of a classic Didot cut of Greek type from around 1800.	
Ibycus4 is as close as possible to Ibycus3 in all possible
respects, but there are some improved set widths and pair-kernings
which might clobber old carefully adjusted text spacings
such as Alexandrian shaped poetry.

A sample input file is provided in iby4text.tex or ibycus4.ltx

PLAIN TeX USAGE:   \input iby4text

	then: \setgreek10/12 (or other reasonable combination 
				of pointsize and leading)

	then: Latin text \GK{}a)rxai=a gra'mmata\RM{} Latin again.

		NOTE that the ) is a smooth breathing, not a parenthesis.

LaTeX2e USAGE:  \usepackage{ibycus4}

	then: Latin text {\greek{a)rxai=a gra'mmata}} Latin again.
		(Note the double braces, there is a font change here.)

	change font size with the \fontsize macro, thus:
 		
		\fontsize{14}{17pt}\selectfont
        

The TeX files in $TEXMF/tex/generic/ibycus4 together with the METAFONT
files in $TEXMF/fonts/source/public/ibycus4 {\em especially
ibycus4.map} are intended to provide a reasonable degree of
compatibility between David Packard Jr.'s Ibycus/TLG system, and the
TeX and METAFONT environment.  If you are not using Karl Berry's
path-searching or its equivalent, these TeX files may have to be moved
to an appropriate branch directory of $TEXMF/tex/
                                                               continues . . .

                                                              README Page 2

The TeX files are:

	1.  $TEXMF/tex/generic/ibycus4/ibycus4.tex 
	
	    The driver file for this package (in plain tex).

        1a. $TEXMF/tex/generic/ibycus4/ibycus4.sty

	    The driver file for this package (in LaTeX2e).

	2.  $TEXMF/tex/generic/ibycus4/setiby4.tex 

	    Included by ibygrk.tex unless newnep format is running

	3.  $TEXMF/tex/generic/ibycus4/tlgsqq.tex

	    The name suggests the association with coding of the 
	    Thesaurus Linguae Graecae.

	This file provides uniquely named macros for all combinations
	of letter and accent, so that any invocation of the macro will
	produce a sequence of characters corresponding with the
	entries put into the TFM ligature table.  These sequences may
	always be used to generate accented characters.  They are
	based, with some slight modifications where David Packard's Ibycus
	input coding seems too misleading, on the Ibycus adaptation of
	TLG beta-code.  
	
	For input coding, the parentheses, ) and ( are used for
	breathings, ' (ASCII char '047--acute or single quote) and `
	(ASCII char '140--grave) are used for oxytone and barytone (to
	avoid preemption of the usual TeX excape character) and =
	(ASCII char '075) is used for perispomenon to avoid preemption
	of the active tie character in plain.tex.  + is used for
	dieresis after u or i and for some other special characters.
	| is used for iota subscript and ! (ASCII char '041--\bang) is
	used to call out the "dot-under" convention for partially
	preserved letters in manuscript or epigraphical texts.  Order
	is significant.  Breathings or diereses come first, after the
	affected letter, then accents, then iota subscript or \bang.
	These codings represent the input coding convention, not the
	mapping in the font itself.

	The digraphs, trigraphs etc. can be read from tlgsqq.tex
	Postpositives fall into three order-dependent and 
	exclusive classes--only one from each class may be used
	in any single accented cluster. 

               1                     2                  3	
	      nil                   nil                nil
               ( [asper]             ' [oxytone]        | [iota subscript]
               ) [lenis]             ` [barytone]       ! [dot below letter]
               + [other]             = [perispomene]                 

                                                               continues . . .

                                                              README Page 3

	Some special digraphs are K+ Koppa, k+ koppa, C+ lunate Cigma,
	c+ lunate cigma, s+ sampi (lowercase late form only) and s| which
	forces a medial sigma.
	<< and >> give guillemets (not guillemots as Adobe
	ornithologically supposes) and (( )) give single parentheses
	though care must be taken that the first ( or ) is not
	interpreted as a breathing.  {((} and {))} are safe.

	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	NOTE: THE FOLLOWING CODINGS ARE NOT COMPATIBLE WITH IBYCUS3
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	I have tried to keep incompatible codings to the minimum
	but the ibycus3 versions of the following were extremely
	undesirable.  These are all simplifications of ibycus3 coding.
        %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	The mark of elision is ' or {'} (the form in braces may be
	needed to prevent ' from being read as an accent).
	Single quotes may be provided by ` {`} and ' {'}, (isolate them 
        in braces if necessary). Double quotes are `` {``} and
	'' {''} (isolate in braces if necessary).  < and > are the
	angle brackets used for conjectural supplements. 
        %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	4. ibycus4.map  

	This is {\em exactly} the same file as is used by METAFONT.
	Copy $TEXMF/fonts/source/public/ibycus4/ibycus4.map 
	to the same directory as ibycus4.tex
	or, even better, link it with a symbolic link.
	It is so structured that it can be read by either
	TeX or Metafont.  The mapping is very close to that of GreekKeys,
	which is distributed for the Macintosh by the American
	Philological Association. Other mappings can be created
	in the same manner.

        5. $TEXMF/tex/generic/ibycus4/Uibycus4.fd

	Supporting fd file for LaTeX2e.

	6. $TEXMF/tex/generic/ibycus4/iby4extr.tex

	Access to some editorial symbols for classical editions.

                                                               continues . . .

                                                              README Page 4

	7. $TEXMF/tex/generic/ibygrk/ibycus4.ltx
	   $TEXMF/tex/generic/ibygrk/iby4text.tex
	The exquisite little poem by Ibycus of Rhegium, until recently
	almost the only thing known by him.  (The Ibycus system
	developed by David Packard is only indirectly named after
	the poet.  The direct inspiration was Packard's cat.)

                          M E T A F O N T

The METAFONT part of the package consists of a set of files which use
the original characters of Silvio Levy's greek fonts and combine them
in ways which reflect the increased capabilities of TeX and METAFONT
developed since Levy did the original greek for TeX. The Levy source
files can be got from one of the CTAN archives and placed in
$TEXMF/fonts/source/public/levy
                                where they will automatically become
accessible if you are using a TeX Directory Structure [TDS] layout of
files.  If you are not using a file searching system like Karl Berry's
"kpathsea", see $TEXMF/fonts/source/public/ibycus4/ibycus4.mf for
hints on making the Levy source available.  For directions on the
use and management of Karl Berry's path searching, consult "The TeX
Live Guide, version 2" by Sebastian Rahtz and Michael Goosens, in
{\it TUGboat}. Volume 18 (1997). Pages 81-112, especially pp. 87--9.
Web2c TeX for Unix systems, Thomas Esser's teTeX, and the Solaris package
referenced at http://smc.vnet.net/solaris_2.5.html all use Karl
Berry's path searching.

Ibycus4 METAFONT files are in $TEXMF/fonts/source/public/ibycus4

The most significant changes are:

	1.  The large repertory of initial/medial sigma + letter pairs
	is suppressed from the new fonts, and the new enhanced TFM
	ligature scheme is used instead to provide for the automatic
	differentiation between medial and final sigma.

	2.  The cells thus opened up in the font mapping are used for
	a variety of additional characters:

		a.  A full repertory of vowels with breathings and
		barytone accents (many of these were absent from the
		original).  The various forms of long epsilon and
		omicron with perispomene accent needed for early Attic
		and similar local scripts are provided.

		b.  Lunate sigma, digamma, koppa and sampi are
        	provided (the last in its lowercase late form
		only, since earlier forms are rather problematic
		and are virtually unused even in epigraphical texts).  
	
		c.  A simple iota subscript in a 0.5em character space
		is provided at position '174 for use in unusual

                                                               continues . . .

                                                              README Page 5
	
		groupings.  For all normal usages three additional
		occurences of the glyph are kerned (in the traditional
		sense) far to the left so that they will fit under
		alpha, eta and omega respectively.  These characters
		are called out automatically through the TeX TFM
		ligature system, for which see below.  The glyph under
		eta is shortened slightly to give better clearance
		under the left stem of lowercase eta.  The iota
		subscript glyph retains its simple form in 300dpi
		renditions, and in any bitmap which drops below
		500dpi, but it thins out and develops a slight
		rightward hook at 600dpi and above.

		d. The mechanism of drastic left kerning is also used
		to set dots under letters which cannot be read
		completely from the manuscript or stone.  These dota
		are likewise called out automatically through the TFM
		ligature system.  A final ! {\bang} after any letter
 		or letter with postpositive accents (except those
		with iota subscripts) will produce the dotted form.

        	e.  Angle brackets, half brackets, double quotes, braces,
		a dagger and a doubledagger are now provided (see 
        	iby4extr.tex).

	3.  All characters have been named.  The constructs
	ASCII"A" and oct"000" appear only at lower levels 
	of programming.

	4.  Character spacing has been adjusted through kerning tables,
	particularly around lowercase iota (file ibylig4.mf).
	There is better separation between breathings and accents
	(this has required a redesign of almost all accents) and
	clearance between accent and base letter has been increased.
	The perispomene has been restored to its traditional form with
	a thick center and tapered ends, and the breathings have been
	given shorter, tapered tails.  The deep ink trap between the
	bulb and tail of the breathings has been eliminated.  Accents
	over epsilon have been raised and slightly shortened to give
	better clearance. The accents with diaeresis have been shifted
        up and laterally to clear the dot they lean toward.  

	5.  Font mapping is specified independently of other
 	parameters, in a distinct and separate file (file ibycus4.map).
	In some cases it may be more effective to remap the font
	than to struggle with TeX remapping.  

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                                                              README Page 6

	6.  A programming error which produced the wrong displacement
	value with free-standing accents has been corrected.  Accents
	before uppercase vowels are kerned (in the traditional sense)
	out left to a negative left side bearing of about one unit
	(1/18em) unit so that their escapement does not leave
	excessive space after the preceding word or at the start of a
	line.  They have also been properly pair-kerned with the
	uppercase vowels.

A new naming convention uses "ibycus4" wherever possible, and
the shorter string "iby4" where that would lead to ambiguity.
some of the individual METAFONT character files are simply
taged with the number 4.  8+3 filename compatibility is preserved.
(under protest and with difficulty).   

The names of PK and TFM files follow Karl Berry's font name convention
( 84 is the encoding for Ibycus 4).

Foundry   Facename    Weights   Variants    Encoding_Variants  DesignSize
 
f            ib      [r], b      r, o          84              [10], 9, 8
 
fibr84 fibo84 fibb84 
 
   with METAFONT design-size additions
fibr848 fibo848 fibb848 
fibr849 fibo849 fibb849 
 
Driver files for the Bold Oblique variant can be provided but their use
is discouraged.  These Didot-derived characters do not stand up well
to either boldfacing or obliqueing, and the combination is quite
unfortunate. The typewriter style originally offered with these
designs is quietly forgotten, although the code for it is still
embedded in Silvio Levy's source.	

	Also in the works, a type1 version.

Pierre A. MacKay
Department of Classics
University of Washington
mackay@cs.washington.edu
