hixie: Add a note about HAVE_METADATA vs HAVE_CURRENT_DATA (whatwg r6177)

hixie: Add a note about HAVE_METADATA vs HAVE_CURRENT_DATA (whatwg
r6177)

http://dev.w3.org/cvsweb/html5/spec/Overview.html?r1=1.4950&r2=1.4951&f=h
http://html5.org/tools/web-apps-tracker?from=6176&to=6177

===================================================================
RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.4950
retrieving revision 1.4951
diff -u -d -r1.4950 -r1.4951
--- Overview.html 2 Jun 2011 23:49:02 -0000 1.4950
+++ Overview.html 2 Jun 2011 23:53:50 -0000 1.4951
@@ -23609,7 +23609,11 @@
    playback rate</a>, would not overtake the available data before
    playback reaches the end of the <a href="#media-resource">media resource</a>.</dd>
 
-  </dl><div class="impl">
+  </dl><p class="note">In practice, the difference between <code title="dom-media-HAVE_METADATA"><a href="#dom-media-have_metadata">HAVE_METADATA</a></code> and <code title="dom-media-HAVE_CURRENT_DATA"><a href="#dom-media-have_current_data">HAVE_CURRENT_DATA</a></code> is
+  negligible. Really the only time the difference is relevant is when
+  painting a <code><a href="#the-video-element">video</a></code> element onto a <code><a href="#the-canvas-element">canvas</a></code>,
+  where it distinguishes the case where something will be drawn (<code title="dom-media-HAVE_CURRENT_DATA"><a href="#dom-media-have_current_data">HAVE_CURRENT_DATA</a></code> or
+  greater) from the case where nothing is drawn (<code title="dom-media-HAVE_METADATA"><a href="#dom-media-have_metadata">HAVE_METADATA</a></code> or less).<div class="impl">
 
   <p>When the ready state of a <a href="#media-element">media element</a> whose <code title="dom-media-networkState"><a href="#dom-media-networkstate">networkState</a></code> is not <code title="dom-media-NETWORK_EMPTY"><a href="#dom-media-network_empty">NETWORK_EMPTY</a></code> changes, the
   user agent must follow the steps given below:</p>

Received on Friday, 17 June 2011 09:55:20 UTC