Spec: http://dev.w3.org/csswg/css-device-adapt/
Currently, the actual viewport is used by the layout task as part of the reflow, and the compositor uses the zoom constraints. I'm not sure if anywhere else currently needs access to the constraints (i.e. there's no CSSOM as far as I can tell).
I did not implement sections 9 (viewport <META>) or 10 (handling 'auto' for 'zoom').
Source-Repo: https://github.com/servo/servo
Source-Revision: ccf1e6b9a701cf4ff010fa1f1b4ba9d656d962af
There are several optimizations here:
* We make font families atoms, to allow for quicker comparisons.
* We precalculate an FNV hash of the relevant fields of the font style
structure.
* When obtaining a platform font group, we first check pointer equality
for the font style. If there's no match, we go to the FNV hash. Only
if both caches miss do we construct and cache a font group. Note that
individual fonts are *also* cached; thus there are two layers of
caching here.
15% improvement in total layout thread time for Facebook Timeline.
r? @glennw (since you last worked on `get_layout_font_group_for_style()` IIRC)
Source-Repo: https://github.com/servo/servo
Source-Revision: ba0d28e0023fce2003d64b9caf97fcdbeb7cdb28
(Still off by default. Enable with `RUST_LOG=style`.)
r? @mbrubeck
Source-Repo: https://github.com/servo/servo
Source-Revision: 172aed535be3c34775824dac64ad2b91fc379ad5