- From: Elika Etemad via cvs-syncmail <cvsmail@w3.org>
- Date: Tue, 07 Jun 2011 04:03:42 +0000
- To: public-css-commits@w3.org
Update of /sources/public/csswg/css3-writing-modes
In directory hutz:/tmp/cvs-serv21527
Modified Files:
Overview.src.html
Log Message:
Clean up prose relating to vertical typesetting.
Index: Overview.src.html
===================================================================
RCS file: /sources/public/csswg/css3-writing-modes/Overview.src.html,v
retrieving revision 1.169
retrieving revision 1.170
diff -u -d -r1.169 -r1.170
--- Overview.src.html 7 Jun 2011 03:17:10 -0000 1.169
+++ Overview.src.html 7 Jun 2011 04:03:40 -0000 1.170
@@ -1127,14 +1127,10 @@
and sets the orientation of the line. Current values only
have an effect in vertical writing modes.
- <p id=grapheme-cluster>In this section only, the term <dfn>character</dfn>
- is defined as <em>extended grapheme cluster</em> per [[!UAX29]]. It is
- roughly equivalent to what a language user considers to be a character
- or a basic unit of the script (which might not be a single Unicode
- codepoint).
- The UA may further tailor the definition as allowed by Unicode.
- See <a href="#character-properties">Character Properties</a> for detailed
- information on determing character properties.
+ <p>For readability, the term <i>character</i> is used in place of
+ <em>extended grapheme cluster</em> in this section.
+ See <a href="#character-properties">Characters and Properties</a>
+ for further details.
<p>Values have the following meanings:</p>
@@ -1217,6 +1213,21 @@
(writing-mode is vertical-rl)</p>
</div>
+ <p>The orientation of characters belonging to the Common, Inherited, and Unknown
+ script categories may be UA- or font-dependent in vertical typographic
+ modes:
+ <ul>
+ <li><p>If the font and font system support mixed-orientation typesetting
+ (e.g. the OpenType font used has the <code>vrt2</code>), the
+ UA should rely on that feature to set ''vertical-right'' text. Similarly
+ if the font and font system support upright typesetting
+ (e.g. the OpenType font used has the <code>vert</code> feature) then the
+ UA should rely on that feature to set ''upright'' text.
+ <li><p>If the UA needs to synthesize such features,
+ then the settings in <a href="#vertical-typesetting-details">Appendix C</a>
+ are recommended.
+ </ul>
+
<div class="example">
<p>In the following example, the root element of a horizontal-only document
is set to use ''sideways''. In the rest of the document, the author
@@ -1230,32 +1241,6 @@
</pre>
</div>
-<h4 id="vertical-typesetting">
-Vertical Typesetting</h4>
-
- <p>In vertical typographic modes, any character belonging to a
- vertical script <em>must</em> be set using its base character's
- intrinsic orientation. (See <a href="#script-orientations">Appendix B</a>.)
- Characters belonging to horizontal-only scripts must set sideways
- (for ''vertical-right'') or set upright (for ''upright'') depending on the
- 'text-orientation' property.
-
- <p>The orientation of characters belonging to the Common, Inherited, and Unknown
- script categories may be UA- or font-dependent in vertical typographic
- modes:
-
- <ul>
- <li><p>If the font and font system support mixed-orientation typesetting, the
- UA should rely on that feature to set ''vertical-right'' text. Similarly
- if the font and font system support upright typesetting then the UA should
- rely on that feature to set ''upright'' text.
-
- <li><p>If the UA needs to synthesize such features (e.g. if an OpenType font
- has only the <code>vert</code> but not the <code>vrt2</code> feature),
- then the settings in <a href="#vertical-typesetting-details">Appendix C</a>
- are recommended.
- </ul>
-
<h2 id="abstract-box">
Abstract Box Terminology</h2>
@@ -2228,6 +2213,38 @@
{ unicode-bidi: isolate; }
</pre>
+<h2 id="character-properties" class="no-num">Appendix Q
+Characters and Properties</h2>
+
+ <p>Unicode defines three character-level properties that are referenced
+ in CSS Writing Modes:
+ <dl>
+ <dt><a href="http://www.unicode.org/reports/tr11/#Definitions">East Asian width</a>
+ <dd>Defined in [[!UAX11]] and given as the East_Asian_Width property.
+ <dt><a href="http://www.unicode.org/reports/tr44/#General_Category_Values">General Category</a>
+ <dd>Defined in [[!UAX44]] and given as the General_Category property.
+ <dt><a href="http://www.unicode.org/reports/tr24/#Values">Script property</a>
+ <dd>Defined in [[!UAX24]] and given as the Script property. (UAs should
+ include any ScriptExtensions.txt assignments in this mapping.)
+ </dl>
+
+ <p id=grapheme-cluster>In several sections (as noted), the term
+ <dfn>character</dfn> is defined as <em>extended grapheme cluster</em>
+ per [[!UAX29]]. It is roughly equivalent to what a language user
+ considers to be a character or a basic unit of the script (which
+ might not be a single Unicode codepoint).
+ The UA may further tailor this definition as allowed by Unicode.
+
+ <p>Unicode defines properties for characters, but for 'text-orientation' and
+ <a href="vertical-typesetting-details">Vertical Typesetting Synthesis</a>,
+ it is necessary to determine the properties of a grapheme cluster.
+ For the purposes of CSS Writing Modes, the properties of a grapheme
+ cluster are given by its base character—except in one case:
+ grapheme clusters formed with an Enclosing Mark (Me) of the Common
+ script are considered to be Other Symbols (So) in the Common script.
+ They are assumed to have the same Unicode properties as the
+ Replacement Character U+FFFD.
+
<h2 class="no-num" id="script-orientations">Appendix B:
Bi-orientational Transformations</h2>
<p><em>This section is normative.</em></p>
@@ -2277,6 +2294,14 @@
<p><em>This appendix is non-normative.</em></p>
+ <p>This section defines an algorithm for automatic typesetting of
+ vertical text.
+
+ For readability, the term <i>character</i> is used in place of
+ <em>extended grapheme cluster</em> in this section.
+ See <a href="#character-properties">Characters and Properties</a>
+ for further details.
+
<p class="issue">This section needs careful review.</p>
<p>When 'text-orientation' is either ''vertical-right'' or ''upright'',
@@ -2296,7 +2321,7 @@
font settings if possible).
<li>Set any other characters that are assigned to a script
(i.e. do not belong to the Common, Inherited, or Unknown scripts)
- <a href="#vertical-typesetting">as required by 'text-orientation'</a>.
+ as required by 'text-orientation' and <a href="#script-orientations">Appendix B</a>.
</ol>
<p>When 'text-orientation' is ''vertical-right'', the following settings
@@ -2352,30 +2377,6 @@
If any of these are present, the font is considered to have vertical
font settings available.
-<h2 id="character-properties" class="no-num">Appendix Q
-Characters and Properties</h2>
-
- <p>Unicode only defines properties for characters, but in the definition
- of 'text-orientation' and in
- <a href="vertical-typesetting-details">Vertical Typesetting Synthesis</a>,
- it is necessary to determine the properties of a grapheme cluster.
- For the purposes of CSS Writing Modes, the properties of a grapheme
- cluster are given by its base character—except in one case:
- grapheme clusters formed with an Enclosing Mark (Me) of the Common
- script are considered to be Other Symbols (So) in the Common script
- having the same Unicode properties as the Replacement Character U+FFFD.
-
- <p>Unicode defines three properties that are referenced here:
- <dl>
- <dt><a href="http://www.unicode.org/reports/tr11/#Definitions">East Asian width</a>
- <dd>Defined in [[UAX11]] and given as the East_Asian_Width property.
- <dt><a href="http://www.unicode.org/reports/tr44/#General_Category_Values">General Category</a>
- <dd>Defined in [[UAX44]] and given as the General_Category property.
- <dt><a href="http://www.unicode.org/reports/tr24/#Values">Script property</a>
- <dd>Defined in [[UAX24]] and given as the Script property. (UAs should
- include any ScriptExtensions.txt assignments in this mapping.)
- </dl>
-
<h2 id="intrinsic-sizing" class="no-num">Appendix D:
Intrinsic Dimensions</h2>
Received on Tuesday, 7 June 2011 04:03:43 UTC