- From: Lea Verou <leaverou@gmail.com>
- Date: Sun, 19 Feb 2012 18:31:52 +0200
- To: Rik Cabanier <cabanier@gmail.com>
- CC: public-fx@w3.org
On 19/2/12 17:48, Rik Cabanier wrote:
> Hi Lea,
> I can see how this would be very useful.
> It would also allow people to create libraries with filters that
could be used as short hands.
Exactly! This is one of the benefits I mentioned ;)
> Can you write out a complete example of such a filter?
> Rik
Sure. My imagination is running kinda low at the moment, so lets assume
hue-rotate wasn't already in the draft.
An author would include this filter in an SVG called filterlib.svg
(which could obviously include other filters as well):
<filter id="hue-rotate">
<feColorMatrix type="hueRotate" values="param(angle) 0"/>
</filter>
Note that the syntax of param() and its default value (of 0 here) is
defined in SVGParam [1].
And then would define it as a function in their CSS like so:
@filter {
src: url(/path/to/filterlib.svg#hue-rotate);
name: hue-rotate;
parameters: angle;
default: 0;
}
And then they'd be able to use hue-rotate() as is currently defined by
the Filter Effects draft.
An alternative syntax could include the function name outside the
braces, @keyframes-style:
@filter hue-rotate {
src: url(/path/to/filterlib.svg#hue-rotate);
parameters: angle;
default: 0;
}
`default` isn't really needed in this case, as the SVG already defines a
default, so it could be omitted.
[1]: http://www.w3.org/TR/SVGParam/
--
Lea Verou (http://lea.verou.me | @LeaVerou)
Received on Sunday, 19 February 2012 16:32:25 UTC