-/***@page m17nDatabaseFormat DatabaseFormat
+/***@page m17nDatabaseFormat Data Format of the m17n database
-This section describes the data formats used in the m17n database.
+This section describes formats of data in the m17n database.
@section dbformat General format
-The mdatabase_load () function receives a set of tags and returns the
-contents of database in the form of plist. The keys of the returned
-plist are limited to <tt>Minteger</tt>, <tt>Msymbol</tt>,
-<tt>Mtext</tt>, and <tt>Mplist</tt>. The type of the value is
-unambiguously determined by the corresponding key. If the key is
-<tt>Minteger</tt>, the value is an integer. If the key is
-<tt>Msymbol</tt>, the value is a symbol. And so on.
-
-A number of character representations are possible to represent a
-plist. For instance, we can use the form <tt>(K1:V1, K2:V2,
-... ,Kn:Vn)</tt> to represent a plist whose first property key and
-value are K1 and V1, second key and value are K2 and V2, and so on.
-However, we can use a simpler notation here because the types of
-plists used in the m17n database are fairly restricted.
-
-Hereafter, we use a character representation, which is similar to
-S-expression, to represent a plist. (Actually, the default database
-loader of the m17n library is designed to read data files written in
-this format.)
-
-The representation consists of one or more <i>elements</i>. Each
-element represents a property, i.e. a single element of a plist.
+The mdatabase_load () function returns the data specified by tags in
+the form of plist if the first tag is not @c Mchartable nor @c
+Mcharset. The keys of the returned plist are limited to
+<tt>Minteger</tt>, <tt>Msymbol</tt>, <tt>Mtext</tt>, and
+<tt>Mplist</tt>. The type of the value is unambiguously determined by
+the corresponding key. If the key is <tt>Minteger</tt>, the value is
+an integer. If the key is <tt>Msymbol</tt>, the value is a symbol.
+And so on.
+
+A number of expressions are possible to represent a plist. For
+instance, we can use the form <tt>(K1:V1, K2:V2, ..., Kn:Vn)</tt> to
+represent a plist whose first property key and value are K1 and V1,
+second key and value are K2 and V2, and so on. However, we can use a
+simpler expression here because the types of plists used in the m17n
+database are fairly restricted.
+
+Hereafter, we use an expression, which is similar to S-expression, to
+represent a plist. (Actually, the default database loader of the m17n
+library is designed to read data files written in this expression.)
+
+The expression consists of one or more <i>elements</i>. Each element
+represents a property, i.e. a single element of a plist.
Elements are separated by one or more <i>whitespaces</i>, i.e. a space
(code 32), a tab (code 9), or a newline (code 10). Comments begin
An element that matches the regular expression
<tt>[^-0-9(]([^\\()]|\\.)+</tt> represents a property whose key is
-<tt> Msymbol</tt>. In the element, <tt>\\t</tt> , <tt>\\n</tt>,
+<tt> Msymbol</tt>. In the element, <tt>\\t</tt>, <tt>\\n</tt>,
<tt>\\r</tt>, and <tt>\\e</tt> are replaced with tab (code 9), newline
(code 10), carriage return (code 13), and escape (code 27)
respectively. Other characters following a backslash is interpreted
EXAMPLE
-Here is an example of plist that is written in our S-expression like
-representation.
+Here is an example of plist that is written in the expression
+explained above.
@verbatim
abc 123 (pqr 0xff) "m\"text" (_\\_ ("string" xyz) -456)
@verbatim
FONT-ENCODING ::=
- '(' PER-FONT-INFO * ')'
+ PER-FONT-INFO *
PER-FONT-INFO ::=
'(' FONT-SPEC ENCODING ')'
should be applied to all fonts whose family is "alice0 lao", and
registry is "iso8859-1".
-@c ENCODING is a charset symbol. A font matching @c FONT-SPEC
-supports all characters of the charset, and a character code is mapped
-to the corresponding glyph code of the font by this charset.
+@c ENCODING is a symbol representing a charset. A font matching @c
+FONT-SPEC supports all characters of the charset, and a character code
+is mapped to the corresponding glyph code of the font by this charset.
+
@section fontsize Font Resizing
In some case, a font contains incorrect information about its size
-(typically in the case of a hacked TrueType font), and results in a
+(typically in the case of a hacked TrueType font), which results in a
bad text layout when such a font is used in combination with the other
fonts. To overcome this problem, the m17n library loads information
about font-size correction from the m17n database by the tags \<font,
@verbatim
FONT-RESIZE ::=
- '(' PER-FONT-INFO * ')'
+ PER-FONT-INFO *
PER-FONT-INFO ::=
'(' FONT-SPEC RESIZE-RATIO ')'
@verbatim
FONTSET ::=
- '(' PER-SCRIPT + ')'
+ PER-SCRIPT * PER-CHARSET * FALLBACK *
PER-SCRIPT ::=
'(' SCRIPT PER-LANGUAGE + ')'
PER-LANGUAGE ::=
'(' LANGUAGE FONT-SPEC-ELEMENT + ')'
+PER-CHARSET ::=
+ '(' CHARSET FONT-SPEC-ELEMENT + ')'
+
+FALLBACK ::=
+ FONT-SPEC-ELEMENT
+
FONT-SPEC-ELEMENT ::=
'(' FONT-SPEC [ FLT-NAME ] ')'
')'
@endverbatim
-@c SCRIPT is a symbol of script name (e.g. latin, han), or @c nil. @c
+@c SCRIPT is a symbol of script name (e.g. latin, han) or @c nil. @c
LANGUAGE is a two-letter symbol of language name code defined by ISO
639 (e.g. ja, zh) or @c nil. The meanings of @c FOUNDRY to @c
REGISTRY are the same as @e Font @e Encoding. @c FLT-NAME is a name
"jisx0208.1983-0" for a "han" character that has @c Mlanguage text
propert "ja" if the character is in the repertories of such fonts.
Otherwise, try a font of registry "gb2312.1980-0" or "big5-0". If a
-"han" character doesn not have @c Mlangauge text property, try all
+"han" character does not have @c Mlangauge text property, try all
three fonts.
@section flt Font Layout Table
-Usually, the rendering engine converts character codes of a text into
-glyph codes one by one by consulting information about encoding of
-each selected font. But, for rendering a text that requires
-complicated layouting (e.g. Thai and Indic), such an one to one
-conversion is not sufficient. In addition, some glyphs must be
-shifted 2-dimensionally on the screen. For such a case, a font layout
-table (FLT in short) must be used.
-
-A FLT can contain all the information in OpenType Layout Table (CMAP,
-GSUB, and GPOS) in addition to the information about how to extract a
-grapheme cluster and how to re-order characters.
+Usually, the rendering engine converts character codes of into glyph
+codes one by one by consulting information about encoding of each
+selected font. But, for rendering a text that requires complicated
+layouting (e.g. Thai and Indic), such an one to one conversion is not
+sufficient. In addition, some glyphs must be shifted 2-dimensionally
+on the screen. For such a case, a font layout table (FLT in short)
+must be used.
+
+A FLT can contain the information equivarent to OpenType Layout Table
+(CMAP, GSUB, and GPOS) in addition to the information about how to
+extract a grapheme cluster and how to re-order characters.
The m17n library loads a FLT from the m17n database by the tags
\<font, layouter, FLT-NAME\>. The plist format of the data is as