- From: Calvin Walton via GitHub <sysbot+gh@w3.org>
- Date: Tue, 25 Jul 2023 19:29:08 +0000
- To: public-fxtf-archive@w3.org
According to https://github.com/w3c/fxtf-drafts/issues/517#issuecomment-1572623758 there already exist some browsers on macOS which perform compositing in the `display-p3` colourspace if the display is capable. Adding wording to the specification to state that "legacy" compositing/blending must be performed in sRGB would mean that current browsers which are capable of displaying colours outside the sRGB gamut are not in compliance with the specification. So the "status quo" statement would be to say that "legacy" compositing/blending happens in an implementation-defined colourspace, which will typically be the colourspace of the system's display output. The specification should also note that "legacy" compositing/blending is performed without gamma correction (i.e. without first converting to a linear light or perceptual colourspace). Note that for "Simple alpha compositing" (where the alpha channel of a sample is a value indicating the ratio within the sample coverage area of opaque colour vs full transparency), performing the compositing in linear light is generally considered to be correct. The blending of opaque colours in other blend modes is typically used for artistic effect, and the colour space that they are performed in should be selectable since it will give noticeably different results; a non-linear or perceptual space might be preferred over linear. -- GitHub Notification of comment by kepstin Please view or discuss this issue at https://github.com/w3c/fxtf-drafts/issues/427#issuecomment-1650412640 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Tuesday, 25 July 2023 19:29:09 UTC