When encountering a @font-face rule, StyleComputer will now fire off
a resource request and download the first source URL specified.
Once downloaded, we try to parse it as a TrueType font file, and if it
works, it's added to a cache in StyleComputer. This effectively makes
fonts per-document since every document has its own StyleComputer.
This is very unoptimized and could definitely use some caching, etc.
But it does work on Acid3. :^)
This gets us a bit closer to the recommended algorithms in CSS 2.2 and
CSS Table Module 3.
A couple of table heavy websites (e.g. news.ycombinator.com,
html5test.com, etc.) now look quite okay. :^)
Previously, the whitespace collapsing code had a parameter telling it
whether the previous text node ended in whitespace. This was not
actually necessary, so let's get rid of it.
This patch reimplements inset property resolution based on the new
CSS Positioned Layout specification. Nothing should change for
left/right insets, but we gain support for top/bottom. :^)
Relatively positioned boxes should not affect the *layout* of their
siblings. So instead of applying relative inset as a layout-time
translation on the box, we now perform the adjustment at the paintable
level instead.
This makes position:relative actually work as expected, and exposes some
new bugs we need to take care of for Acid2. :^)
Before this the flex layout didn't take into account the applied
borders or padding while laying out the items.
The child's top and left borders would get painted over the
parent's borders, also due to it not taking borders into account,
children with borders would overlap each other.
Due to it not taking padding into account, the children would get
drawn outside the parent element.
If a C++ object already has a JS wrapper, we don't need to go through
the expensive type checks to figure out which kind of wrapper to create.
Instead, just return the wrapper we already have!
This gives a noticeable increase in smoothness on Acid3, where ~10% of
CPU time was previously spent doing RTTI type checks in wrap(). With
these changes, it's down to ~1%.
...but never allow the resulting height to become negative. This solves
an issue seen on Acid3 where elements with negative vertical margins
expanded the size of their height:auto container instead of shrinking
it, which is the correct behavior. This now works :^)
CSS 2.2 says "Horizontal margins never collapse."
So instead of collapsing them, we now add them together, which makes
negative margins between floating boxes work beautifully.
Instead of TextNode::ChunkIterator having two bool members to remember
things across calls to next(), this patch reorganizes the loop in next()
so that preserved newline/whitespace chunks are emitted right away
instead of in an awkward deferred way.
Instead of emitting a Text item with the "should_force_break" flag set
to true, newlines in newline-preserving text content now timply turn
into ForcedBreak items. This makes the <pre> element work again.
From the HTML spec:
Modulo platform conventions, it is suggested that the following
elements should be considered as focusable areas and be sequentially
focusable:
...
- button elements
- select elements
- textarea elements
...
Also add a spec link to the existing HTMLAnchorElement::is_focusable().
Note that this still doesn't allow triggering keyboard-focused buttons,
checkboxes, or radio buttons - we don't seem to run the expected
activation behavior for any of them.
From the HTML spec:
Modulo platform conventions, it is suggested that the following
elements should be considered as focusable areas and be sequentially
focusable:
...
- input elements whose type attribute are not in the Hidden state
...
I believe this is all of them, but I may have missed some.
Several properties technically do not allow negative numbers but the
description says to accept these as valid, and then clamp them
afterwards to the desired range. As such, we don't reject them during
parsing.
This might not be entirely correct, but neither was using the completely
ad-hoc parse_html_length(), and this is the last user of that API so
let's move off of it.
For layers that require indirect painting (due to opacity, transform,
etc.) we create a nested PaintContext. Until now, that PaintContext
was created fresh without transferring all the state from the parent
PaintContext.
