- From: Jake Archibald via GitHub <sysbot+gh@w3.org>
- Date: Wed, 15 Mar 2023 12:55:36 +0000
- To: public-css-archive@w3.org
Summary for CSSWG: We use `mix-blend-mode: plus-lighter` on the old & new views, plus `isolation: isolate` on the image-pair, in order to create a true cross-fade. Isolation isn't free performance-wise. Some transition groups only have an old view, or only new view. This happens when an element with a particular `view-transition-name` only exists on one side of the transition. Isolation is unnecessary in these cases. ## Option 1: Apply isolation & blend mode styles only when both old & new views are present This would be observable in `getComputedStyle`. It would also result in a different rendering if the developer gives the image-pair a background color, since some contents will plus-lighter blend with that background, and others wouldn't. However, if you set a background on the image-pair, it like that you'd want to set blending to normal anyway. We already apply lots of styles dynamically in a view transition, such as width, height, transform etc of transition groups. ## Option 2: Optimise internally for cases where isolation and blending is unnecessary `getComputedStyle` would still see isolation and plus-lighter, but the rendering engine would avoid rendering to another buffer in cases where doing so would have no visual effect. It's unclear how tricky this would be. -- GitHub Notification of comment by jakearchibald Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/7814#issuecomment-1469957527 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Wednesday, 15 March 2023 12:55:37 UTC