CSS WG Blog – Minutes Seattle F2F Part V: 2014-01-29 AM – Page Selectors and Page Groups, Seoul F2F, CSS2.1, Region Styling, Scroll Snap Points, will-change, Blending and Compositing

Minutes Seattle F2F Part V: 2014-01-29 AM – Page Selectors and Page Groups, Seoul F2F, CSS2.1, Region Styling, Scroll Snap Points, will-change, Blending and Compositing

By Dael Jackson February 22, 2014 (Permalink)
Categories: resolutions

Page Selectors and Page Groups

Resolved: page: name is not inheritable, creates a group, but does not force page breaks between groups of the same name (for compat). First page of the group might be the last of another group. Delete the page-group property.
Resolved: Keep :nth() as the name, but extend functionality like L4 :nth-child() to solve the “first of group” problem.
Resolved: Add :first(A) to select first page of an A group. (A:first only selects a first page of the doc that also happens to be named A).

Full Minutes || Spec Referenced

Seoul F2F

Dates are May 19 to 21 hosted by Samsung. Meetup on May 22.

Full Minutes

CSS2.1

Resolved: Change to MAY on default object size shrinking from 300×150 for small devices.

Full Minutes

Region Styling

Resolved: Shift Region Styling out of Regions, merge with page-based and overflow-fragment-based styling (which will all use the same basic syntax and cascade rules), put into CSS4 Cascade for now.

Full Minutes || Specs Referenced: Regions, CSS4 Cascade

Scroll Snap Points

Microsoft presented its proposal for CSS scroll-snapping properties. There was a lot of feedback.

Some use cases presented:
- Scrolling through a photo album, wanting to snap each photo to the center of the window, or slightly offset from the center of the window.
- Scrolling through photos filmstrip style, wanting to snap to every 5 photographs.
- Scrolling in 2D: snapping to faces in a photo or points on a map.
- Effect of zooming on the use cases; whether properties set for one zoom level will still work in larger/smaller viewports than expected.
Some structural concerns:
- Removing the ‘elements’ value and just merging lists of snap points.
- Having the elements within a scroller, not the scroller, determine scroll-snapping behaviors.
- Syntactic concerns (consistency with the rest of CSS on capitalization and hyphenation, use of commas).
- Discussion of -x/-y properties and/or use of position.
- Multiple snap points per element.
- Interaction with box-sizing vs. using box-sizing keywords.
Behavioral concerns:
- Distinguishing mandatory vs. proximity behavior. Possibly mixing the two within a scroller.
- Snapping points vs. snapping areas.
- Distinguishing various snapping behaviors, e.g. accelerating towards a snap position vs. resisting leaving a snap position.

Microsoft will draw up a new draft for review by the WG after considering all feedback; currently withholding FWPD until the draft better represents the views of the WG.

Full Minutes

`will-change`

Discussed will-change proposal, interaction with performance and optimization, and effects on stacking context generation. Tab was tasked with taking the proposal to the Performance WG for feedback. Holding off on FPWD for feedback on general approach.
Resolved: Publish will-change in the CSS WG repo as an Unofficial Draft

Full Minutes