- From: Brad Kemper <brad.kemper@gmail.com>
- Date: Sat, 17 Jul 2010 11:54:10 -0700
- To: Tab Atkins Jr. <jackalmage@gmail.com>
- Cc: 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 Jul 16, 2010, at 3:30 PM, Tab Atkins Jr. wrote: > On Fri, Jul 16, 2010 at 3:14 PM, Aryeh Gregor <Simetrical+w3c@gmail.com> wrote: >> On Thu, Jul 15, 2010 at 5:41 PM, Tab Atkins Jr. <jackalmage@gmail.com> wrote: >>> ?_? That sounds plenty testable to me. Grab the pixels, verify they >>> form a gradient, then check where the 99% point is hit. Sounds easy >>> to me. >> >> What algorithm do you propose to "verify they form a gradient"? Other >> than specifying a canonical type of gradient (say, Gaussian) and just >> comparing against that? > > By "forms a gradient" I mean "creates a monotonic transition from one > color to another". That's easy to verify by just walking the pixels. More accurately, it is from one _opacity_ (the shadow color's Alpha component) to another (transparent). It does look like 'one color to another' if it is a single shadow against a solid-color background, with no other elements overlapping it. But that isn't always the case.
Received on Saturday, 17 July 2010 18:54:52 UTC