[fxtf-drafts] [filter-effects] Allow intermediate negative colour values

• From: Conrad Irwin via GitHub <sysbot+gh@w3.org>
• Date: Wed, 06 Sep 2017 01:32:04 +0000
• To: public-fxtf-archive@w3.org
• Message-ID: <issues.opened-255454407-1504661515-sysbot+gh@w3.org>

ConradIrwin has just created a new issue for https://github.com/w3c/fxtf-drafts:

== [filter-effects] Allow intermediate negative colour values ==
ref. https://www.w3.org/TR/SVG11/filters.html#feColorMatrixElement

I'm trying to invert the colour of a page (white background -> black background) but preserve the color of images. A naive solution is to do this:

```
body {
  filter: invert(1) hue-rotate(180deg);
}
img {
  filter: hue-rotate(180deg) invert(1);
}
```

But this doesn't quite work because the channel outputs of the first hue-rotate is truncated to [0..255], this causes the two hue-rotates (which should be a no-op) to lose information.

Please view or discuss this issue at https://github.com/w3c/fxtf-drafts/issues/221 using your GitHub account

Received on Wednesday, 6 September 2017 01:32:00 UTC