--- a/webvtt/webvtt.html Sun Aug 11 17:40:05 2013 +1000
+++ b/webvtt/webvtt.html Mon Aug 12 11:17:58 2013 +1000
@@ -613,6 +613,10 @@
relative to the width of the video, and <a title="text track cue text position">text
position</a> and <a title="text track cue size">size</a> percentages are relative to
the height of the video.</p>
+
+ <p>The <a title="text track cue writing direction">writing direction</a> defaults to
+ <a title="text track cue horizontal writing direction">horizontal</a>.</p>
+
</dd>
<dt><dfn title="text track cue snap-to-lines flag">A snap-to-lines flag</dfn>
@@ -626,6 +630,9 @@
title-safe area on user agents that use overscan. Cues with the flag unset will be positioned as
requested (modulo overlap avoidance if multiple cues are in the same place).</p>
+ <p>By default, the <a title="text track cue snap-to-lines flag">snap-to-lines flag</a>
+ is set to 'true'.</p>
+
</dd>
<dt><dfn title="text track cue line position">A line position</dfn>
@@ -634,7 +641,7 @@
the <a title="text track cue writing direction">writing direction</a> and <a
title="text track cue snap-to-lines flag">snap-to-lines flag</a> of the cue, or the special
value <dfn title="text track cue automatic line position">auto</dfn>, which means the position
- is to depend on the other active tracks.</p>
+ is to depend on the other active cues.</p>
<p>A <a>text track cue</a> has a <dfn>text track cue computed line position</dfn> whose
value is that returned by the following algorithm, which is defined in terms of the other
@@ -683,39 +690,67 @@
</dd>
- <dt><dfn title="text track cue text position">A text position</dfn>
- <dd>
- <p>A number giving the position of the text of the cue within each line. If the cue is not within a region, to be interpreted as a percentage of the video, as defined by the <span title="text track cue writing direction">writing direction</span>, otherwise to be interpreted as a percentage of the region width.</p>
- </dd>
-
<dt><dfn title="text track cue size">A size</dfn>
<dd>
<p>A number giving the size of the box within which the text of each line of the cue is to be
- aligned, to be interpreted as a percentage of the video, as defined by the <a title="text
- track cue writing direction">writing direction</a>.</p>
+ rendered, to be interpreted as a percentage of the video, as defined by the <a title="text
+ track cue writing direction">writing direction</a>. This box is called the <dfn>cue box</dfn>.</p>
</dd>
+ <dt><dfn title="text track cue text position">A text position</dfn>
+ <dd>
+ <p>A number giving the position of the text within the <a>cue box</a>. If the cue is not within
+ a region, the value is to be interpreted as a percentage of the box's
+ <a title="text track cue size">size</a>, otherwise as a percentage of the region width.</p>
+
+ <p>A <a>text track cue</a> has a default <a>text track cue text position</a>, which is defined
+ in terms of the value of the <a>text track cue alignment</a>:</p>
+
+ <ol>
+
+ <li>For <a title="text track cue start alignment">start aligned</a> cues: 0%.</li>
+
+ <li>For <a title="text track cue middle alignment">middle aligned</a> cues: 50%.</li>
+
+ <li>For <a title="text track cue end alignment">end aligned</a> cues: 100%.</li>
+
+ <li>For <a title="text track cue left alignment">left aligned</a> cues with left-to-right
+ <i>paragraph direction</i> <a href="#refsBIDI">[BIDI]</a>: 0%, otherwise 100%.</li>
+
+ <li>For <a title="text track cue right alignment">right aligned</a> cues with left-to-right
+ <i>paragraph direction</i> <a href="#refsBIDI">[BIDI]</a>: 100%, otherwise 0%.</li>
+
+ </ol>
+
+ <p class="note">Since the default value of the <a>text track cue text position</a> is
+ <a title="text track cue middle alignment">middle</a>, if there is no
+ <a>text track cue alignment</a> setting for a cue, the <a>text track cue text position</a>
+ defaults to 50%.</p>
+
+ </dd>
+
+
<dt><dfn title="text track cue alignment">An alignment</dfn>
<dd>
- <p>An alignment for the text of each line of the cue, one of:</p>
+ <p>An alignment for all lines of text within the <a>cue box</a>, one of:</p>
<dl>
<dt><dfn title="text track cue start alignment">Start alignment</dfn></dt>
- <dd>The text is aligned towards its start side.</dd>
+ <dd>The text is aligned towards the box's start side.</dd>
<dt><dfn title="text track cue middle alignment">Middle alignment</dfn></dt>
- <dd>The text is aligned centered between its start and end sides.</dd>
+ <dd>The text is aligned centered between the box's start and end sides.</dd>
<dt><dfn title="text track cue end alignment">End alignment</dfn></dt>
- <dd>The text is aligned towards its end side.</dd>
+ <dd>The text is aligned towards the box's end side.</dd>
<dt><dfn title="text track cue left alignment">Left alignment</dfn></dt>
- <dd>The text is aligned to the left.</dd>
+ <dd>The text is aligned to the box's left side.</dd>
<dt><dfn title="text track cue right alignment">Right alignment</dfn></dt>
- <dd>The text is aligned to the right.</dd>
+ <dd>The text is aligned to the box's right side.</dd>
</dl>
@@ -723,6 +758,40 @@
the <a title="text track cue writing direction">writing direction</a>. <a
href="#refsBIDI">[BIDI]</a></p>
+ <p>By default, the value of the <a>text track cue alignment</a> is
+ <a title="text track cue middle alignment">middle aligned</a>.</p>
+
+ <p>A <a>text track cue</a> has a <dfn>computed text position anchor point</dfn>,
+ which signifies the point in the text whose position within the <a>cue box</a> can be manipulated
+ through the <a title="text track cue text position">text position</a> cue setting. The value of
+ the <a>computed text position anchor point</a> is set as follows:</p>
+
+ <ol>
+
+ <li>For <a title="text track cue start alignment">start aligned</a> cues: the first character
+ of each line of text is positioned at the <a>text track cue text position</a> point within
+ the <a>cue box</a>.</li>
+
+ <li>For <a title="text track cue middle alignment">middle aligned</a> cues: the middle character
+ of each line of text is positioned at the <a>text track cue text position</a> point within
+ the <a>cue box</a>.</li>
+
+ <li>For <a title="text track cue end alignment">end aligned</a> cues: the last character
+ of each line of text is positioned at the <a>text track cue text position</a> point within
+ the <a>cue box</a>.</li>
+
+ <li>For <a title="text track cue left alignment">left aligned</a> cues with left-to-right
+ <i>paragraph direction</i> <a href="#refsBIDI">[BIDI]</a>: the first character of each line of
+ text is positioned at the <a>text track cue text position</a> point within the <a>cue box</a>,
+ otherwise the last character is positioned there.</li>
+
+ <li>For <a title="text track cue right alignment">right aligned</a> cues with left-to-right
+ <i>paragraph direction</i> <a href="#refsBIDI">[BIDI]</a>: the last character of each line of
+ text is positioned at the <a>text track cue text position</a> point within the <a>cue box</a>,
+ otherwise the first character is positioned there.</li>
+
+ </ol>
+
</dd>
<dt><dfn title="text track cue region identifier">A region identifier</dfn></dt>
@@ -1474,10 +1543,10 @@
<ul class="brief">
<li>A <a>WebVTT vertical text cue setting</a>.</li> <!-- vertical:rl/lr -->
<li>A <a>WebVTT line position cue setting</a>.</li> <!-- line:100% line:1 line:-1 -->
- <li>A <a>WebVTT text position cue setting</a>.</li> <!-- position:100% -->
<li>A <a>WebVTT size cue setting</a>.</li> <!-- size:100% -->
+ <li>A <a>WebVTT text position cue setting</a>.</li> <!-- position:100% -->
<li>A <a>WebVTT alignment cue setting</a>.</li> <!-- align:start/middle/end/left/right -->
- <li>A <a>WebVTT region cue setting</a>.</li> <!-- region:fred -->
+ <li>A <a>WebVTT region cue setting</a>.</li> <!-- region:fred -->
</ul>
<p class="note">A <a>WebVTT cue settings list</a> gives configuration
@@ -1534,6 +1603,26 @@
line is numbered 0), negative line numbers from the bottom of the
frame (the bottom line is numbered −1).</p>
+ <p>A <dfn>WebVTT size cue setting</dfn> consists of the
+ following components, in the order given:</p>
+
+ <ol>
+ <li><p>The string "<code title="">size</code>" as the <a>WebVTT cue setting name</a>.</p></li>
+ <li><p>A U+003A COLON character (:).</p></li>
+ <li>As the <a>WebVTT cue setting value</a>:
+ <ol>
+ <li>One or more <a>ASCII digits</a>.</li>
+ <li>A U+0025 PERCENT SIGN character (%).</li>
+ </ol>
+ </li>
+ </ol>
+
+ <p class="note">A <a>WebVTT size cue setting</a> configures
+ the size of the <a>cue box</a> in the same direction as the <a>WebVTT text
+ position cue setting</a>. For horizontal cues, this is the width
+ of the <a>cue box</a>. It is given as a percentage of the width of the
+ frame.</p>
+
<p>A <dfn>WebVTT text position cue setting</dfn> consists of the
following components, in the order given:</p>
@@ -1553,29 +1642,9 @@
the <a>WebVTT line position cue setting</a>. For horizontal
cues, this is the horizontal position. The <a>WebVTT text
position cue setting</a> is given as a percentage, calculated
- from the edge of the frame that the text begins (so for
+ from the edge of the <a>cue box</a> that the text begins (so for
left-to-right English text, the left edge).</p>
- <p>A <dfn>WebVTT size cue setting</dfn> consists of the
- following components, in the order given:</p>
-
- <ol>
- <li><p>The string "<code title="">size</code>" as the <a>WebVTT cue setting name</a>.</p></li>
- <li><p>A U+003A COLON character (:).</p></li>
- <li>As the <a>WebVTT cue setting value</a>:
- <ol>
- <li>One or more <a>ASCII digits</a>.</li>
- <li>A U+0025 PERCENT SIGN character (%).</li>
- </ol>
- </li>
- </ol>
-
- <p class="note">A <a>WebVTT size cue setting</a> configures
- the size of the cue in the same direction as the <a>WebVTT text
- position cue setting</a>. For horizontal cues, this is the width
- of the cue. It is given as a percentage of the width of the
- frame.</p>
-
<p>A <dfn>WebVTT alignment cue setting</dfn> consists of the
following components, in the order given:</p>