[css3-fonts] editorial fixes in cluster matching section

Author: John Daggett

css-fonts/Fonts.html

@@ -3143,10 +3143,25 @@ <h3 id=font-style-matching><span class=secno>5.2 </span>Matching font
    with the appropriate style based on other font properties and then
    determining whether a glyph exists for the given character. This is done
    using the <dfn id=character-map>character map</dfn> of the font, data
-   which maps characters to the default glyph for that character. Codepoint
-   sequences consisting of a base character followed by a sequence of
-   combining characters are treated slightly differently, see the section on
-   <a href="#cluster-matching">cluster matching</a> below.
+   which maps characters to the default glyph for that character. A font is
+   considered to <dfn id=support>support</dfn> a given character if (1) the
+   character is contained in the font's <a
+   href="#character-map"><em>character map</em></a> and (2) if required by
+   the containing script, shaping information is available for that
+   character.
+
+  <p>Some legacy fonts may include a given character in the <a
+   href="#character-map"><em>character map</em></a> but lack the shaping
+   information (e.g. <a
+   href="http://www.microsoft.com/typography/otspec/ttochap1.htm">OpenType
+   layout tables</a> or <a
+   href="http://scripts.sil.org/cms/scripts/page.php?site_id=projects&amp;item_id=graphite_techAbout">Graphite
+   tables</a>) necessary for correctly rendering text runs containing that
+   character.
+
+  <p>Codepoint sequences consisting of a base character followed by a
+   sequence of combining characters are treated slightly differently, see the
+   section on <a href="#cluster-matching">cluster matching</a> below.
 
   <p>For this procedure, the <dfn id=default-face>default face</dfn> for a
    given font family is defined to be the face that would be selected if all
@@ -3329,31 +3344,18 @@ <h3 id=font-style-matching><span class=secno>5.2 </span>Matching font
 
   <h3 id=cluster-matching><span class=secno>5.3 </span>Cluster matching</h3>
 
-  <p>When text contains characters such as combining diacritics, ideally the
-   base character should be rendered using the same font as the diacritic,
-   this assures proper placement of the diacritic. For this reason, the font
-   matching algorithm for clusters is more specialized than the general case
-   of matching a single character by itself. For sequences containing
-   variation selectors, which indicate the precise glyph to be used for a
-   given character, user agents always attempt <a
-   href="#system-font-fallback"><em>system font fallback</em></a> to find the
-   appropriate glyph before using the default glyph of the base character.
-
-  <p>A font is considered to <em>support</em> a given character if (1) the
-   character is contained in the font's <a
-   href="#character-map"><em>character map</em></a> and (2) if required by
-   the containing script, shaping information is available for that
-   character. Some legacy fonts may include a given character in the <a
-   href="#character-map"><em>character map</em></a> but lack the shaping
-   information (e.g. <a
-   href="http://www.microsoft.com/typography/otspec/ttochap1.htm">OpenType
-   layout tables</a> or <a
-   href="http://scripts.sil.org/cms/scripts/page.php?site_id=projects&amp;item_id=graphite_techAbout">Graphite
-   tables</a>) necessary for correctly rendering text runs containing that
-   character.
-
-  <p>A sequence of codepoints containing combining diacritics or other
-   modifiers is termed a grapheme cluster (see <a href="#CSS3TEXT"
+  <p>When text contains characters such as combining marks, ideally the base
+   character should be rendered using the same font as the mark, this assures
+   proper placement of the mark. For this reason, the font matching algorithm
+   for clusters is more specialized than the general case of matching a
+   single character by itself. For sequences containing variation selectors,
+   which indicate the precise glyph to be used for a given character, user
+   agents always attempt <a href="#system-font-fallback"><em>system font
+   fallback</em></a> to find the appropriate glyph before using the default
+   glyph of the base character.
+
+  <p>A sequence of codepoints containing combining mark or other modifiers is
+   termed a grapheme cluster (see <a href="#CSS3TEXT"
    rel=biblioentry>[CSS3TEXT]<!--{{CSS3TEXT}}--></a> for a more complete
    description). For a given cluster containing a base character, <em>b</em>
    and a sequence of combining characters <em>c1, c2…</em>, the entire
@@ -3367,27 +3369,33 @@ <h3 id=cluster-matching><span class=secno>5.3 </span>Cluster matching</h3>
       completely supported by the font, select this font for the sequence.
 
      <li>If a sequence of multiple codepoints is canonically equivalent to a
-      single character and the font supports that character, select this font
-      for the sequence.
+      single character and the font <a href="#support"><em
+      title=support>supports</em></a> that character, select this font for
+      the sequence.
     </ol>
 
    <li>If no font was found in the font list in step 1:
     <ol>
      <li>If <em>c1</em> is a variation selector, system fallback must be used
-      to find a font that supports the full sequence of <em>b + c1</em>. If
-      no font on the system supports the full sequence, match the single
+      to find a font that <a href="#support"><em
+      title=support>supports</em></a> the full sequence of <em>b + c1</em>.
+      If no font on the system <a href="#support"><em
+      title=support>supports</em></a> the full sequence, match the single
       character <em>b</em> using the normal procedure for matching single
       characters and ignore the variation selector. Note: a sequence with
-      more than one variation selector is treated as an encoding error and
-      the trailing selectors are ignored.
+      more than one variation selector must be treated as an encoding error
+      and the trailing selectors must be ignored. <a href="#UNICODE6"
+      rel=biblioentry>[UNICODE6]<!--{{!UNICODE6}}--></a>
 
      <li>Otherwise, the user agent may optionally use system font fallback to
-      match a font that supports the entire cluster.
+      match a font that <a href="#support"><em
+      title=support>supports</em></a> the entire cluster.
     </ol>
 
    <li>If no font is found in step 2, use the matching sequence from step 1
-    to determine the longest sequence that is completely matched by a font in
-    the font list and attempt to match the remaining combining characters
+    to determine the longest sequence that is completely <a
+    href="#support"><em title=support>supported</em></a> by a font in the
+    font list and attempt to match the remaining combining characters
     separately using the rules for single characters.
   </ol>
 
@@ -4225,7 +4233,7 @@ <h3 id=font-variant-caps-prop><span class=secno>6.6 </span>Capitalization:
    <pre>blockquote            { font-style: italic; }
 blockquote:first-line { font-variant: small-caps; }
 
-&lt;blockquote><a href="http://lists.w3.org/Archives/Public/www-style/2009Dec/0036.html" style="text-decoration: none">I'll be honor-bound to slap them like a haddock.</a>&lt;/blockquote>
+&lt;blockquote><a href="http://lists.w3.org/Archives/Public/www-style/2009Dec/0036.html" style="text-decoration: none; border: none;">I'll be honor-bound to slap them like a haddock.</a>&lt;/blockquote>
 </pre>
   </div>
   <!-- prop: font-variant-numeric -->
@@ -6737,6 +6745,8 @@ <h2 class=no-num id=index>Index</h2>
 
    <li>super, <a href="#super" title=super><strong>6.5</strong></a>
 
+   <li>support, <a href="#support" title=support><strong>5.2</strong></a>
+
    <li>swash, <a href="#swash" title=swash><strong>6.8</strong></a>
 
    <li>system font fallback, <a href="#system-font-fallback" title="system