- From: Sylvain Galineau <sylvaing@microsoft.com>
- Date: Fri, 15 Jan 2010 23:32:36 +0000
- To: "public-css-testsuite@w3.org" <public-css-testsuite@w3.org>
At least two CSS3 Color testcases compare an RGB foreground color with an RGBA equivalent: http://www.w3.org/Style/CSS/Test/CSS3/Color/current/html4/t040202-rgba-a0-6-a.htm http://www.w3.org/Style/CSS/Test/CSS3/Color/current/html4/t0302-opacity-basic-0-6-a.htm Both testcases verify that rgb(102,102,102) looks like either rgba(0,0,0,0.6) or rgb(0,0,0) with 0.6 opacity. This works fine with background colors but may be problematic for UAs that apply anti-aliasing and other font smoothing algorithms since the output of the latter will vary depending on the text color. In this case, the rgba() version of the text may end up looking darker than expected since the font smoothing code will initially run on black text against a white background. Subsequently applying alpha on the smoothed text will thus not look identical to smoothing rgba(102,102,102,1) text.
Received on Friday, 15 January 2010 23:33:13 UTC