[] (0) Allow non-wall-clock clocks for media playback, since in pract…

…ice UAs sync things to the soundcard's ring buffer, or similar, to avoid stuttering. Fixing http://www.w3.org/Bugs/Public/show_bug.cgi?id=12339 git-svn-id: http://svn.whatwg.org/webapps@5976 340c8d12-0b0e-0410-8428-c7bf67bfef74
whatwg · Apr 8, 2011 · 92cf98c · 92cf98c
1 parent 54096b4
commit 92cf98c
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diff --git a/complete.html b/complete.html
@@ -27150,6 +27150,17 @@ <h5 id=offsets-into-the-media-resource><span class=secno>4.8.10.6 </span>Offsets
   possible position</a> (as defined below) using the established
   <a href=#media-timeline>media timeline</a>, is greater than or equal to zero.</p>
 
+  <p>The <a href=#media-timeline>media timeline</a> also has an associated clock.
+  Which clock is used is user-agent defined, and may be <a href=#media-resource>media
+  resource</a>-dependent, but it should approximate the user's wall
+  clock.</p>
+
+<!--CONTROLLER-->
+  <p class=note>All the <a href=#media-element title="media element">media
+  elements</a> that share <a href=#current-media-controller>current media controller</a> use
+  the same clock for their <a href=#media-timeline>media timeline</a>.</p>
+<!--CONTROLLER-->
+
   <p><a href=#media-element title="media element">Media elements</a> have a
   <dfn id=current-playback-position>current playback position</dfn>, which must initially (i.e. in
   the absence of <a href=#media-data>media data</a>) be zero seconds. The
@@ -27881,7 +27892,7 @@ <h5 id=playing-the-media-resource><span class=secno>4.8.10.8 </span>Playing the
   <a href=#fully-active>fully active</a> <code><a href=#document>Document</a></code>, its <a href=#current-playback-position>current
   playback position</a> must increase monotonically at
   <a href=#effective-playback-rate>effective playback rate</a> units of media time per unit time
-  of wall clock time.</p> <!--XXX will change with bug 12339 -->
+  of the <a href=#media-timeline>media timeline</a>'s clock.</p>
 
   <p class=note>The <a href=#effective-playback-rate>effective playback rate</a> can be 0.0,
   in which case the <a href=#current-playback-position>current playback position</a> doesn't

diff --git a/index b/index
@@ -27130,6 +27130,17 @@ interface <dfn id=htmlaudioelement>HTMLAudioElement</dfn> : <a href=#htmlmediael
   possible position</a> (as defined below) using the established
   <a href=#media-timeline>media timeline</a>, is greater than or equal to zero.</p>
 
+  <p>The <a href=#media-timeline>media timeline</a> also has an associated clock.
+  Which clock is used is user-agent defined, and may be <a href=#media-resource>media
+  resource</a>-dependent, but it should approximate the user's wall
+  clock.</p>
+
+<!--CONTROLLER-->
+  <p class=note>All the <a href=#media-element title="media element">media
+  elements</a> that share <a href=#current-media-controller>current media controller</a> use
+  the same clock for their <a href=#media-timeline>media timeline</a>.</p>
+<!--CONTROLLER-->
+
   <p><a href=#media-element title="media element">Media elements</a> have a
   <dfn id=current-playback-position>current playback position</dfn>, which must initially (i.e. in
   the absence of <a href=#media-data>media data</a>) be zero seconds. The
@@ -27861,7 +27872,7 @@ interface <dfn id=htmlaudioelement>HTMLAudioElement</dfn> : <a href=#htmlmediael
   <a href=#fully-active>fully active</a> <code><a href=#document>Document</a></code>, its <a href=#current-playback-position>current
   playback position</a> must increase monotonically at
   <a href=#effective-playback-rate>effective playback rate</a> units of media time per unit time
-  of wall clock time.</p> <!--XXX will change with bug 12339 -->
+  of the <a href=#media-timeline>media timeline</a>'s clock.</p>
 
   <p class=note>The <a href=#effective-playback-rate>effective playback rate</a> can be 0.0,
   in which case the <a href=#current-playback-position>current playback position</a> doesn't

diff --git a/source b/source
@@ -29334,6 +29334,17 @@ interface <dfn>HTMLAudioElement</dfn> : <span>HTMLMediaElement</span> {};</pre>
   possible position</span> (as defined below) using the established
   <span>media timeline</span>, is greater than or equal to zero.</p>
 
+  <p>The <span>media timeline</span> also has an associated clock.
+  Which clock is used is user-agent defined, and may be <span>media
+  resource</span>-dependent, but it should approximate the user's wall
+  clock.</p>
+
+<!--END w3c-html--><!--CONTROLLER-->
+  <p class="note">All the <span title="media element">media
+  elements</span> that share <span>current media controller</span> use
+  the same clock for their <span>media timeline</span>.</p>
+<!--START w3c-html--><!--CONTROLLER-->
+
   <p><span title="media element">Media elements</span> have a
   <dfn>current playback position</dfn>, which must initially (i.e. in
   the absence of <span>media data</span>) be zero seconds. The
@@ -30221,7 +30232,7 @@ interface <dfn>HTMLAudioElement</dfn> : <span>HTMLMediaElement</span> {};</pre>
   <span>fully active</span> <code>Document</code>, its <span>current
   playback position</span> must increase monotonically at
   <span>effective playback rate</span> units of media time per unit time
-  of wall clock time.</p> <!--XXX will change with bug 12339 -->
+  of the <span>media timeline</span>'s clock.</p>
 
   <p class="note">The <span>effective playback rate</span> can be 0.0,
   in which case the <span>current playback position</span> doesn't