[html5] r5976 - [] (0) Allow non-wall-clock clocks for media playback, since in practice UAs syn [...]

[whatwg at whatwg.org]

Author: ianh
Date: 2011-04-08 00:01:00 -0700 (Fri, 08 Apr 2011)
New Revision: 5976

Modified:
   complete.html
   index
   source
Log:
[] (0) Allow non-wall-clock clocks for media playback, since in practice 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

Modified: complete.html
===================================================================
--- complete.html	2011-04-08 06:53:56 UTC (rev 5975)
+++ complete.html	2011-04-08 07:01:00 UTC (rev 5976)
@@ -27150,6 +27150,17 @@
   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 @@
   <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

Modified: index
===================================================================
--- index	2011-04-08 06:53:56 UTC (rev 5975)
+++ index	2011-04-08 07:01:00 UTC (rev 5976)
@@ -27130,6 +27130,17 @@
   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 @@
   <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

Modified: source
===================================================================
--- source	2011-04-08 06:53:56 UTC (rev 5975)
+++ source	2011-04-08 07:01:00 UTC (rev 5976)
@@ -29334,6 +29334,17 @@
   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 @@
   <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