- From: Tab Atkins Jr. <jackalmage@gmail.com>
- Date: Tue, 27 Jul 2010 07:50:23 -0700
- To: Sylvain Galineau <sylvaing@microsoft.com>
- Cc: Brad Kemper <brad.kemper@gmail.com>, Dennis Amrouche <dennis@screenlabor.de>, Brian Manthos <brianman@microsoft.com>, Aryeh Gregor <Simetrical+w3c@gmail.com>, "L. David Baron" <dbaron@dbaron.org>, Simon Fraser <smfr@me.com>, Brendan Kenny <bckenny@gmail.com>, www-style list <www-style@w3.org>
On Mon, Jul 26, 2010 at 8:58 PM, Sylvain Galineau <sylvaing@microsoft.com> wrote: >> From: www-style-request@w3.org [mailto:www-style-request@w3.org] On >> Behalf Of Tab Atkins Jr. > > >> So, yeah, like Brad says, if the "range of pixels within which the >> shadow becomes effectively invisible to the human eye" is a bit off at >> very high shadow blur lengths, you'll never notice. It's a pretty >> unimportant point. > > To the human eye, sure. Now, can we talk about testing implementations > for conformance ? I've suggested precisely what I think the criteria should be already. The shadow must approximate a gaussian blur with a stdev equal to half the length, with each pixel being within 5% (of the whole color space, so about 12 "color units" to each side) of the color that a true gaussian would be. That should fix behavior sufficiently to make everyone that conforms "look the same", while allowing enough wiggle room for the current approximations to a gaussian (triple box blur, generally) to fit. The Skia blur that Chrome uses on some platforms will not be conformant. ~TJ
Received on Tuesday, 27 July 2010 14:59:26 UTC