- From: poot <cvsmail@w3.org>
- Date: Tue, 5 Aug 2008 19:00:02 +0900 (JST)
- To: public-html-diffs@w3.org
How to handle transparent images for toDataURL(). Just allow the UA to
premultiply the alpha and output that whie dropping the alpha channel,
instead of worrying about the background color or whatnot. It's up to
authors to make the background color non-transparent. (whatwg r2004)
toDataURL(type)
http://people.w3.org/mike/diffs/html5/spec/Overview.1.1193.html#todataurl0
http://people.w3.org/mike/diffs/html5/spec/Overview.diff.html
http://dev.w3.org/cvsweb/html5/spec/Overview.html?r1=1.1192&r2=1.1193&f=h
http://html5.org/tools/web-apps-tracker?from=2003&to=2004
===================================================================
RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.1192
retrieving revision 1.1193
diff -u -d -r1.1192 -r1.1193
--- Overview.html 5 Aug 2008 09:29:05 -0000 1.1192
+++ Overview.html 5 Aug 2008 09:57:10 -0000 1.1193
@@ -20827,6 +20827,11 @@
or even maybe <code>image/svg+xml</code> if the implementation actually
keeps enough information to reliably render an SVG image from the canvas.
+ <p>For image types that do not support an alpha channel, the image must be
+ composited onto a solid black background using the source-over operator,
+ and the resulting image must be the one used to create the <code
+ title="">data:</code> URL.
+
<p>Only support for <code>image/png</code> is required. User agents may
support other types. If the user agent does not support the requested
type, it must return the image using the PNG format.
Received on Tuesday, 5 August 2008 10:00:39 UTC