[css-text] Clean up paragraph about applying letter-spacing to cursive scripts.

Author: fantasai

css-text/Overview.html

@@ -2813,17 +2813,14 @@ <h3 id=letter-spacing><span class=secno>8.2. </span> Tracking: the ‘<a
    an “fi” ligature should not be used as it will prevent even spacing of
    the text.
 
-  <p>UAs may apply letter-spacing to cursive scripts. In this case, UAs
-   should extend the space between disjoint characters as specified above
-   <em>and</em> extend the visible connection between cursively connected
-   characters by the same amount (rather than leaving a gap). The UA may use
-   glyph substitution or other font capabilities to spread out the letters.
-   If the UA cannot expand a cursive script without breaking the cursive
-   connections, it should not apply letter-spacing between characters of that
-   script at all.
-
-  <p class=issue>Current UAs just put gaps between joined letters in cursive
-   scripts.
+  <p>If it is able, the UA <em>may</em> apply letter-spacing to <a
+   href="#cursive-scripts"><i>cursive scripts</i></a> by translating the
+   total spacing distributed to a run of such <a
+   href="#letter0"><i>letters</i></a> into some form of cursive elongation
+   for that run. Otherwise, if the UA cannot expand text from a <i>cursive
+   script</i> without breaking its cursive connections, it <em>must not</em>
+   apply spacing between any pair of that script's <a
+   href="#letter0"><i>letters</i></a> at all.
 
   <h2 id=edge-effects><span class=secno>9. </span> Edge Effects</h2>
 

css-text/Overview.src.html

@@ -2084,15 +2084,13 @@ <h3 id="letter-spacing">
       an “fi” ligature should not be used
       as it will prevent even spacing of the text.
 
-    <p>UAs may apply letter-spacing to cursive scripts. In this case, UAs
-      should extend the space between disjoint characters as specified above
-      <em>and</em> extend the visible connection between cursively connected
-      characters by the same amount (rather than leaving a gap). The UA may
-      use glyph substitution or other font capabilities to spread out the
-      letters. If the UA  cannot expand a cursive script without breaking
-      the cursive connections, it should not apply letter-spacing between
-      characters of that script at all.</p>
-    <p class="issue">Current UAs just put gaps between joined letters in cursive scripts.
+    <p>If it is able, the UA <em>may</em> apply letter-spacing to <i>cursive scripts</i>
+    by translating the total spacing distributed to a run of such <i>letters</i>
+    into some form of cursive elongation for that run.
+    Otherwise, if the UA cannot expand text from a <i>cursive script</i>
+    without breaking its cursive connections,
+    it <em>must not</em> apply spacing
+    between any pair of that script's <i>letters</i> at all.
 
 <h2 id="edge-effects">
   Edge Effects</h2>

css-writing-modes/Overview.src.html

@@ -2209,30 +2209,28 @@ <h3 id="text-combine-horizontal">
   Value: none | all | [ digits &lt;integer>? ]
   Initial: none
   Applies to: non-replaced inline elements
-  Inherited: <a href="http://lists.w3.org/Archives/Public/www-style/2013Jul/0154.html" class="issue">???</a>
+  Inherited: yes
   Percentages: n/a
   Media: visual
   Computed value: specified keyword, plus integer if ''digits''
   Animatable: no
   Canonical order: n/a
   </pre>
 
-  <p>This property allows the combination of multiple characters into the
-    space of a single character. This property only has an effect
-    in vertical writing modes. Values have the following meanings:</p>
+  <p>This property specifies the combination of multiple characters into the space of a single character.
+    If the combined text is wider than 1em, the UA must fit the contents within 1em, see below.
+    The resulting composition is treated as a single glyph for the purposes of layout and decoration.
+    This property only has an effect in vertical writing modes. Values have the following meanings:
 
   <dl>
     <dt><dfn value for=text-combine-horizontal>none</dfn>
     <dd>No special processing.</dd>
 
     <dt><dfn value for=text-combine-horizontal>all</dfn>
     <dd>In vertical writing modes,
-      attempt to display the text contents of the element horizontally within the vertical line box.
-      If the contents are wider than 1em, the UA must fit the contents within 1em, see below.
-      The resulting composition is treated as a single glyph for the purposes
-      of layout and decoration.
-      If the content contains any element boundaries this is treated as
-      ''text-combine-horizontal: none'' on the element and any descendants.
+      attempt to typeset all consecutive <i>characters</i> within the element
+      horizontally within the vertical line box,
+      such that they take up the space of a single character.
 <!--
     <dt><dfn value for=text-combine-horizontal>numeric</dfn>
     <dd>Within the element, each sequence of consecutive horizontal numbers
@@ -2245,9 +2243,9 @@ <h3 id="text-combine-horizontal">
 -->
     <dt><dfn value for=text-combine-horizontal>digits <var>&lt;integer></var>?</dfn>
     <dd>Within the element, each maximal sequence of consecutive ASCII digits (U+0030&ndash;U+0039)
-      that has as many or fewer characters than the integer given is treated
-      as if it were in an anonymous inline box with
-      ''text-combine-horizontal: all''.
+      that has as many or fewer characters than the integer given
+      is typeset horizontally within the vertical line box,
+      such that it takes up the space of a single character.
       When the integer is omitted, 2 is used.
       Integers outside the range 2-4 are invalid.
 <!--
@@ -2314,6 +2312,30 @@ <h3 id="text-combine-horizontal">
       <p class="caption">Example of mis-applied <i lang="ja" title=''>tate-chu-yoko</i></p>
     </div>
   </div>
+<!--
+<h4 id="text-combine-runs">
+Text Run Rules</h4>
+
+  <p>This feature can only combine plain text,
+  therefore each combined text run must contain only text: no element boundaries.
+  Because the property inherits,
+  the UA must ensure that the contents of the element effecting the combination
+  are not part of a sequence of the specified character pattern
+  that happens to begin or end outside the element;
+  if so, then the text is laid out normally, as if 'text-combine-horizontal' were ''none''.
+
+  <div class="example">
+    <p>For example, the following sequence of “1234” would be combined:
+    <pre>&lt;tcy>&lt;span>1234&lt;/span>&lt;/tcy></pre>
+    <p>However, the next example would not result in any combined text,
+    even though the inner span (which has inherited a value of ''digits 4'') contains only text,
+    because “12“ and “34” are both part of the larger sequence “1234”
+    <pre>&lt;tcy>12&lt;span>34&lt;/span>&lt;/tcy></pre>
+    <p>Similarly,
+  </div>
+-->
+<h4 id="text-combine-compression">
+Compression Rules</h4>
 
   <p>In order to preserve typographic color when compressing the text to 1em,
     when the combined text consists of more than one <i>character</i>,
@@ -2469,9 +2491,9 @@ <h3 class="no-num" id="changes-201211">
   2012 CSS Writing Modes Module Level 3 <abbr title="Working Draft">WD</abbr></a></h3>
   <ul>
     <li>Added back ''digits'' value of 'text-combine-horizontal' and tightened up rules for compressing text.
+    <li>Defined better analysis of text to be combined.
     <li>Various fixes/clarifications to orthogonal flows.
     <li>Updated references to UTR50 and how this specification use its values.
-    <li>Removed interaction of 'text-combine-horizontal' and 'font-variant: full-width' and added a note instead.
   </ul>
 
   <h3 class="no-num" id="changes-201205">