hixie: Mention the case of getContext('webgl') returning null due to hardware limitations. (whatwg r6130)

hixie: Mention the case of getContext('webgl') returning null due to
hardware limitations. (whatwg r6130)

http://dev.w3.org/cvsweb/html5/spec/Overview.html?r1=1.4929&r2=1.4930&f=h
http://html5.org/tools/web-apps-tracker?from=6129&to=6130

===================================================================
RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.4929
retrieving revision 1.4930
diff -u -d -r1.4929 -r1.4930
--- Overview.html 12 May 2011 06:05:28 -0000 1.4929
+++ Overview.html 12 May 2011 06:58:13 -0000 1.4930
@@ -356,11 +356,12 @@
    <h2 class="no-num no-toc" id="a-vocabulary-and-associated-apis-for-html-and-xhtml">A vocabulary and associated APIs for HTML and XHTML</h2>
    <h2 class="no-num no-toc" id="w3c-working-draft-24-may-2011">W3C Working Draft 24 May 2011</h2>
    <dl><dt>This Version:</dt>
-    <dd><a href="http://www.w3.org/TR/2011/LC-html5-20110524/">http://www.w3.org/TR/2011/LC-html5-20110524/</a></dd>
+    <dd><a href="http://www.w3.org/TR/2011/WD-html5-20110524/">http://www.w3.org/TR/2011/LC-html5-20110524/</a></dd>
     <dt>Latest Published Version:</dt>
     <dd><a href="http://www.w3.org/TR/html5/">http://www.w3.org/TR/html5/</a></dd>
     <dt>Latest Editor's Draft:</dt>
     <dd><a class="latest-link" href="http://dev.w3.org/html5/spec/Overview.html">http://dev.w3.org/html5/spec/Overview.html</a></dd>
+
     <dt>Previous Versions:</dt>
     <dd><a href="http://www.w3.org/TR/2011/WD-html5-20110405/">http://www.w3.org/TR/2011/WD-html5-20110405/</a></dd>
     <dd><a href="http://www.w3.org/TR/2011/WD-html5-20110113/">http://www.w3.org/TR/2011/WD-html5-20110113/</a></dd>
@@ -27153,9 +27154,21 @@
   <ol><li><p>Let <var title="">contextId</var> be the first argument to
    the method.</li>
 
-   <li><p>If <var title="">contextId</var> is not the name of a
-   context supported by the user agent, return null and abort these
-   steps.</li>
+   <li>
+
+    <p>If <var title="">contextId</var> is not the name of a context
+    supported by the user agent, return null and abort these
+    steps.</p>
+
+    <p class="note">An example of this would be a user agent that
+    theoretically supports the "<code title="canvas-context-webgl">webgl</code>" 3D context, in the case
+    where the platform does not have hardware support for OpenGL and
+    the user agent does not have a software OpenGL implementation.
+    Despite the user agent recognising the "<code title="canvas-context-webgl">webgl</code>" name, it would return
+    null at this step because that context is not, in practice,
+    supported at the time of the call.</p>
+
+   </li>
 
    <li><p>If the element has a <a href="#primary-context">primary context</a> and that
    context's entry in the <a href="http://wiki.whatwg.org/wiki/CanvasContexts">WHATWG Wiki

Received on Thursday, 12 May 2011 07:15:53 UTC