- From: Dirk Schulze <dschulze@adobe.com>
- Date: Sun, 4 Jun 2017 08:19:18 +0000
- To: Tab Atkins Jr. <jackalmage@gmail.com>
- CC: Amelia Bellamy-Royds <amelia.bellamy.royds@gmail.com>, Chris Lilley <chris@w3.org>, public-fx <public-fx@w3.org>
> On 15. Mar 2016, at 01:52, Tab Atkins Jr. <jackalmage@gmail.com> wrote: > > On Mon, Feb 1, 2016 at 2:25 PM, Amelia Bellamy-Royds > <amelia.bellamy.royds@gmail.com> wrote: >> On 1 February 2016 at 15:02, Chris Lilley <chris@w3.org> wrote: >>> The ED of filters says that the lacuna value for the grayscale filter is >>> zero. >>> https://drafts.fxtf.org/filters/#FilterProperty >>> >>> However: >>> >>> - the syntax does not seem to allow the argument to be omitted so how >>> can the lacuna value be used >>> - if it did, then 0 is an odd value >>> >>> 0 means no change. Thus seems unintuitive. I would expect grayscale() >>> to be equivalent to grayscale(100%) which is likely what authors would >>> expect and would be convenient for the most common use case "make this >>> grayscale". >>> >>> Suggested fix: >>> >>> - change the grayscale filter syntax to make the argument optional >>> - change the lacuna value to 1 >>> >>> Btw I added some tests for grayscale since there was only one (100%) >>> so I added 1, 0, 0% and 300% as well. >> >> For what it's worth, this seems to be how -webkit-filter is implemented. In >> other words, -webkit-filter: grayscale() applies 100% grayscale filter (in >> Chrome anyway, haven't tested Safari). >> >> For implementers of the standard property, neither Edge nor Firefox >> currently support the function without a parameter, so changing the lacuna >> value would not break anything that isn't already broken. >> >> I also agree that it is more useful/logical to have the default function be >> complete grayscale. > > Yes, it should be omittable. All of the functions need similar edits. > > I'm not even sure what "the lacuna value for interpolation" *is*. > First, "Lacuna value" is an SVG-ism defined in that spec; CSS specs > instead use normal English and talk about what to do when something is > omitted. ^_^ Second, this is the default value *in general*; I don't > know what this has to do with interpolation. Values had been optional in the past but after explicit requests from the CSS WG were made required. I am fine with making them optional again but that should be decided and recorded in a WG meeting IMO. Greetings, Dirk > > ~TJ >
Received on Sunday, 4 June 2017 08:19:56 UTC