windows: fix line height handling
hi there!
on windows, this change properly scales a font's line height by its size.
previously, line height was not scaled to the font's size at all, which meant line heights become worse and worse the further you scaled away from the font's design size (in either direction, larger or smaller).
this change makes the `line_gap` ratio and size scale with the font size. i've hand checked that the new computed `line_gap` matches the effective heights in chrome and firefox when `line-height = normal` for a bunch of system fonts. (servo's rendering quality on windows is a different story, though).
i believe this also solves #16476.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
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Avoid panic when reloading a page with mouse event handlers
This PR fixes issue #16057, by nullifying `topmost_mouse_over_target` inside of the `handle_exit_pipeline_msg` method, in case owner document is the same as the pipeline document that is being destroyed.
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
Testing was done manually, by running `./mach run (-r|-d) "http://localhost:8000/minimal.html" `, where `minimal.html` contains `<div onmouseover="location.reload()" onmouseout="this.clientLeft">hi there</div>`.
r?@jdm
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Now we have AnimatableLonghand (to do with animatability) and
TransitionProperty (to do with transitionability), we should move
nscssproperty_id_is_animatable to be part of the former group.
Currently properties that are discretely animated cannot be
transitioned. Now that TransitionProperty should only be used for
transitions, we can redefine it to treat non-transitionable properties
as unsupported. This should allow us to simplify the code and make it
more self-documenting (e.g. making TransitionProperty actually relate to
transitions).
In the next few patches we move all non-transition related code over to
using AnimatableLonghand instead of TransitionProperty. This will allow
us to re-purpose TransitionProperty to represent only properties that
can be transitioned (i.e. excluding discrete properties) as well as
simplifying the code by removing the need to deal with shorthands and
the "all" value in places that do not need to handle those values.
I saw this function appear in the profiles at #17329.
It was under set_device, which isn't a Stylo path, but probably worth there
anyway.
This reduces the reported overhead of RulesIterator::next in perf from ~8% to
0.46%
This type, which we will use in the next patch in this series, can
represent only longhands whose animation type is not "none". By
introducing this type, we can later restrict the meaning of
TransitionProperty to only cover properties whose animation type is not
"none" OR "discrete" (since currently CSS transitions should not animate
properties whose animation type is discrete). Doing so will also mean
that CSS transitions ignore the 'display' property by default.
Furthermore, introducing this type will allow the animation code to
clearly document when a property is allowed to be a shorthand or
unanimatable property and when it is expected to be an animatable
longhand. This, in turn, will allow us to remove a few
no-longer-necessary checks and simplify the code.
This allows simplifying the code somewhat and means we can ignore
unanimated shorthands a little sooner. Furthermore, it removes the odd
inconsistency where TransitionProperty only included animatable
longhands but allowed all shorthands regardless of whether or not they
were animatable.
style: Avoid quadratic time serialization of a declaration block.
At least when the longhands aren't custom properties.
We should also look into not serializing the style attribute eagerly when it's
not needed... But a lot of code currently rely on attribute values being
dereferenciables to &str, so that's harder to fix.
We should really look into all those vectors around too, but that's probably
less urgent.
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By looking at the shorthands, not the other way around, given a longhand uses to
not appear in multiple longhands.
This makes the testcase go to 430ms on my machine.
This could be even faster having a static LonghandIdSet per shorthand, I guess,
but this is not done in this PR.
Concretely we avoid allocating and scanning a temporary vector of longhands not
yet serialized for each shorthand.
This doesn't save a lot of time in Linux, but I bet it's somewhat important on
OSX.
At least when the longhands aren't custom properties.
We should also look into not serializing the style attribute eagerly when it's
not needed... But a lot of code currently rely on attribute values being
dereferenciables to &str, so that's harder to fix.
We should really look into all those vectors around too, but that's probably
less urgent.
