- From: Dean Jackson <dino@apple.com>
- Date: Thu, 21 Apr 2011 05:12:39 +1000
- To: "Tab Atkins Jr." <jackalmage@gmail.com>
- Cc: public-fx@w3.org
On 20/04/2011, at 11:44 AM, Tab Atkins Jr. wrote: > On Tue, Apr 19, 2011 at 6:14 PM, Dean Jackson <dino@apple.com> wrote: >> Then I was thinking that these generator effects are similar to other parts of CSS, in particular gradients. There have been some proposals in this area. For example: >> >> - WebKit's -webkit-canvas value, which allows an element to use a canvas element as an image in background, border, whatever. >> - Mozilla's -moz-element, which does the same but with the rendering of any element >> >> Examples of generators may be: >> >> - checkerboards >> - stripes >> - noise >> - star shines >> >> They don't sound too useful in isolation, but graphics artists may feel otherwise. Anyway, the important part of this message is the 3rd paragraph. I don't want to complicate the syntax or implementations. "SVG" filters provide the functionality, so it definitely isn't essential. > > Yup, these are just generated images, and should probably be defined > in the Image Values module. Excellent. Are you responsible for that spec? And will you take this on - whatever that means, maybe an email to www-style? > > Of the existing Filter primitives that do this, feFlood is already > doable with the image() function (just doing "image(blue)" produces a > pure-blue image, because it's the fallback color for an empty list of > image declarations). feImage is done with the url() function. > feTurbulence is something we should add, as perlin noise is really > useful to add a bit of non-uniformity to designs (I've seen a lot of > recent stuff where a design is done just with gradients, but with a > noise image laid on top); it should probably be a perlinnoise() > function or something. I think noise() or turbulence() are good names. I don't see a need to be so exact unless we're going to add multiple algorithms. > > Stripes are already doable with linear gradients. It turns out that > you can get a checkerboard with just two linear gradients combined > together <http://leaverou.me/css3patterns/>. I'd suggest a new value for this. Just because it is possible doesn't mean we should encourage it. Do you see a chessboard and think "oh, overlapping rotated repeating gradients with hard edges"? > I dunno about > haloes/star shines, but I'm not averse to them if they're useful. It's not terribly common, but I can imagine people wanting to bling-up their site header with a little sunburst (which animates across the text as the drop shadow moves in sync). Or use <blink>. But I'm a big fan of starting small, especially if you know that you're not making enhancements hard to add at a later stage. So probably no need for this now. Dean
Received on Wednesday, 20 April 2011 19:13:09 UTC