Note that these aren't full implementations of the bindings. This
mostly implements the low hanging fruit (namely, basic reflections)
There are some attributes that should be USVString instead of
DOMString. However, USVString is a slightly different definition
of DOMString, so it should suffice for now.
LibWeb keeps growing and the Web namespace is filling up fast.
Let's put DOM stuff into Web::DOM, just like we already started doing
with SVG stuff in Web::SVG.
This commit starts adding a basic SVG element. Currently, svg elements
have support for the width and height properties, as well as the stroke,
stroke-width, and fill properties. The only child element supported
is the path element, as most other graphical elements are just shorthand
for paths.
If we know the width, but not the height, we have to *divide* with the
intrinsic ratio to get the height (not multiply.) :^)
This makes things like <img width=300 src=image.png> work right.
Images were added before replaced element layout knew about intrinsic
sizes, so this was a bit backwards. We now instead transfer the known
intrinsic sizes from the ImageLoader to the LayoutImage.
We now remember the last candidate fragment when hit testing past the
right end of text and use that as the fallback result if nothing else
matches. This makes it possible to drag-select outside the line boxes
in a way that feels mostly natural. :^)
We use this to ensure that we're always working with a selection where
the start() is before the end() in document order. That simplifies all
the logic around this.
Text selection currently works at the LayoutNode level. The root of the
layout tree has a LayoutRange selection() which in turn has two
LayoutPosition objects: start() and end().
A LayoutPosition is a LayoutNode + a text offset into that node.
We handle the selection painting in LayoutText::paint_fragment(), after
the normal painting is finished. The basic mechanism is that each
LayoutFragment is queried for its selection_rect(), and if a non-empty
rect is returned, we clip to it and paint the text once more.
Sometimes people make tables with a specific width. In those cases,
we can't just use the auto-sizing algorithm, but instead have to
respect whatever width the content specifies.
This is a bit rickety right now, since we don't implement generation
of anonymous table boxes.
The basic mechanism here is that block layout (which table-cell uses)
now has a virtual way of asking for the width of the logical containing
block. This is necessary as table-row does not produce a block-level
element and so was previously unable to provide a containing block
width for table-cell layout.
If the table has a non-auto specified width, we now interpret that as
a request to use fixed table layout. This will evolve over time. :^)
Margin collapsing is a bit confusing, but if I understand correctly,
when collapsing a box's top margin with the vertically adjacent
sibling box above, we should "skip over" empty (0-height) boxes and
collapse their margin with *their* vertically adjacent sibling box
above, etc. Iterating until we hit the first non-empty in-flow block.
This pulls up the bottom part of the face on ACID2. :^)
We could previously place a box next to a preceding sibling with
position:fixed, which is wrong since fixed-position elements are taken
out of the normal flow.
When highlighting a node in the inspector, we now paint three overlays:
- The content box (magenta)
- The padding box (cyan)
- The margin box (yellow)
This makes it a lot easier to debug layout issues.
Sometimes we end up with an empty line box at the bottom of a block.
Instead of worrying about this in all the places we split into lines,
just remove the trailing box (if any) after splitting is finshed.
To make this possible, I also had to give each LayoutNode a Document&
so it can resolve document-specific colors correctly. There's probably
ways to avoid having this extra member by resolving colors later, but
this works for now.
This patch also adds the ability for Length to contain percentage
values. This is a little off-spec, but will make storing and dealing
with lengths a lot easier.
To resolve a Length to a px-or-auto Length, there are now helpers
for that. After calling them, you no longer have to think about
em, rem, %, and such things.
StyleProperties is really only the specified "input" to what eventually
becomes the used/computed style we use for layout and painting.
Unlike StyleProperties, LayoutStyle will have strongly typed values for
everything it contains (i.e no CSS::ValueID or strings, etc.)
This first patch moves z-index into LayoutStyle.
This avoids having to query the StyleProperties hash map whenever we
need to know if an element is absolutely positioned. This was extremely
hot in interactive window resize profiles.
In this case, we need to undo the right-side offsetting, since the
width computation algorithm will already have stretched the width to
accomodate both the side constraints.
