- From: Connor Brewster via GitHub <sysbot+gh@w3.org>
- Date: Thu, 13 Jun 2019 16:51:27 +0000
- To: public-fxtf-archive@w3.org
cbrewster has just created a new issue for https://github.com/w3c/fxtf-drafts:
== [filter-effects-1] feDropShadowElement definition does not match implementations ==
Spec: https://drafts.fxtf.org/filter-effects/#feDropShadowElement
According to the spec for `<feDropShadow>`, it's result should be equivalent to a combination of other filter primitives; however, this is not always the case in browser implementations.
Example Case:
```html
<svg xmlns="http://www.w3.org/2000/svg" viewbox="0 0 1024 1024">
<defs>
<filter id="specDropShadow">
<feGaussianBlur in="SourceAlpha" stdDeviation="30"/>
<feOffset dx="50" dy="50" result="offsetblur"/>
<feFlood flood-color="green" flood-opacity="1"/>
<feComposite in2="offsetblur" operator="in"/>
<feMerge>
<feMergeNode/>
<feMergeNode in="SourceGraphic"/>
</feMerge>
</filter>
<filter id="dropShadow">
<feDropShadow stdDeviation="30" dx="50" dy="50" flood-color="green"/>
</filter>
</defs>
<circle fill="yellow" cx="75" cy="75" r="70" filter="url(#specDropShadow)" />
<circle fill="yellow" cx="250" cy="75" r="70" filter="url(#dropShadow)" />
</svg>
```
Result (Firefox; Safari and Chrome produce a similar result):
In this example case, the left circle is the drop shadow using a combination of filter primitives defined by the spec to be equivalent to the `feDropShadow` primitive and the right circle is using the actual `feDropShadow` primitive.
Clipping occurs after the first `feGaussianBlur`, which becomes visible after the blur has been offset; however, most browser implementations don't appear to clip the blur before offsetting.
Please view or discuss this issue at https://github.com/w3c/fxtf-drafts/issues/343 using your GitHub account
Received on Thursday, 13 June 2019 16:51:29 UTC