- From: Patrick H. Lauke <redux@splintered.co.uk>
- Date: Wed, 11 Jan 2017 09:08:02 +0000
- To: Gregg C Vanderheiden <greggvan@umd.edu>
- Cc: GLWAI Guidelines WG org <w3c-wai-gl@w3.org>
On 11/01/2017 05:04, Gregg C Vanderheiden wrote: > > >> On Jan 10, 2017, at 6:46 PM, Patrick H. Lauke >> <redux@splintered.co.uk> wrote: >> >> I'm failing to see why the "33% of any 10 degree visual field on >> the screen" has the issues (1 and 2) you noted, but the existing >> ".006 steradians within any 10 degree visual field on the screen >> (25% of any 10 degree visual field on the screen) " from WCAG 2.0's >> current definition for general flash and red flash thresholds >> doesn't? >> >> Does "visual field on the screen" not, in essence, mean the full >> size of the screen/viewport? And if not, isn't the general >> flash/red flash definition not also fundamentally flawed as it >> can't take into account physical screen size / viewing distance / >> etc, regardless of the existence of a "tool"? > > Hi Patrick > > I said that it DID have the same problems — and worse. But there was > a tool that did the measurement automatically — so no one had to > figure out the bits. So you'd agree that rephrasing both the general flash and red flash measurement in WCAG 2.0 and the proposed animation measures as something more in the format "1/3 of the viewport" (or whatever the most appropriate fraction of the visible viewport works best / approximates the existing "25% of any 10 degree visual field on the screen") or similar would be possible? Doing that would demystify the baffling measurement. If there's then also a tool that helps with the calculations, even better, but it would make the measurement as written in the spec a lot less obscure. > And I suggested you might look at that approach here too. And gave > other advice that related to the flash work. Read my comments > again. Maybe I didnt write them clearly enough. I think I initially talked across purposes https://lists.w3.org/Archives/Public/w3c-wai-gl/2017JanMar/0160.html ... apologies. P -- Patrick H. Lauke www.splintered.co.uk | https://github.com/patrickhlauke http://flickr.com/photos/redux/ | http://redux.deviantart.com twitter: @patrick_h_lauke | skype: patrick_h_lauke
Received on Wednesday, 11 January 2017 09:08:32 UTC