The idea here is to let us decide ahead of time what components to paint
depending on the size available. We currently paint each component left-
to-right, until we run out of room. This implicitly gives priority to
the left-most components.
We will soon paint volume controls on the right-side of the timeline.
Subjectively, they should have a higher priority than, say, the timeline
scrubbing bar (i.e. it's more important to be able to mute audio than to
seek). By computing these components before painting, we can more easily
allocate sections to the components in priority order, until the area
remaining has been depleted.
It can take some time to download / decode a media resource. During this
time, its duration is set to NaN. The media control box would then have
some odd rendering glitches as it tried to treat NaN as an actual time.
Once we do have a duration, we also must ensure the media control box is
updated.
Previously, all StackingContexts which were scaled using CSS transforms
were hard-coded to use BilinearBlend. This fix maps specified
image-rendering properties to reasonable ScalingModes for painting.
This moves the painting of the media timeout out of VideoPaintable into
a base MediaPaintable. This is to allow re-using the same timeline logic
and controls for audio elements.
Although DistinctNumeric, which is supposed to abstract the underlying
type, was used to represent CSSPixels, we have a whole bunch of places
in the layout code that assume CSSPixels::value() returns a
floating-point type. This assumption makes it difficult to replace the
underlying type in CSSPixels with a non-floating type.
To make it easier to transition CSSPixels to fixed-point math, one step
we can take is to prevent access to the underlying type using value()
and instead use explicit conversions with the to_float(), to_double(),
and to_int() methods.
Previously, we did an evenodd fill for everything which while for most
SVGs works, it is not correct default (it should be nonzero), and broke
some SVGs. This fixes a few of the icons on https://shopify.com/.
The implementation of painting for SVG text follows the same pattern
as the implementation of painting for SVG geometries. However, instead
of reusing the existing PaintableWithLines to draw text, a new class
called SVGTextPaintable is introduced. because everything that is
painted inside an SVG is expected to inherit from SVGGraphicsPaintable.
Therefore reusing the text painting from regular text nodes would
require significant refactoring.
The spec for the `<use>` element requires a shadow tree for the
rendered content, so we need to be able to escape shadow trees when
rendering svg content.
This makes it possible to set a pseudo-element as the inspected node
using Document::set_inspected_node(), Document then provides
inspected_layout_node() for the painting related functions.
These markers are rendered as equilateral triangles pointing right and
down respectively. As we currently don't implement writing-mode the
closed marker does not respect it.
Stacking contexts are sorted after building a tree of them. They are
sorted by z-index first, DOM tree order second.
Sorting was previously *very* slow on pages with many stacking contexts.
That was because the sort() function used Node::is_before() in the
quick_sort comparator to see if one StackingContext was before another.
is_before() does tree traversal and can take quite a long time per call.
This patch avoids all that by letting StackingContext know its index
among all StackingContexts within the same document in tree order.
There's a noticeable snappiness increase on the CSS-FLEXBOX-1 spec page,
for instance. :^)
Somewhere the path bounding box in the layout and the actual draw path
are getting slightly mismatched. This results in partly clipped bits of
SVGs. The paths are already clipped to the containing SVG, and the size
of the path in the layout is computed from the bounding box, so it is
probably safe just to remove this clipping for now.
This fixes a plethora of rounding problems on many websites.
In the future, we may want to replace this with fixed-point arithmetic
(bug #18566) for performance (and consistency with other engines),
but in the meantime this makes the web look a bit better. :^)
There's a lot more things that could be converted to doubles, which
would reduce the amount of casting necessary in this patch.
We can do that incrementally, however.
This avoids a ton of work when painting large documents. Even though it
would eventually get clipped by the painter anyway, by bailing out
earlier, we avoid a lot more work (UTF-8 iteration, OpenType lookups,
etc).
It would be even nicer if we could skip entire line boxes, but we don't
have a fast way to get the bounding rect of a line box at the moment.
Previously, calling `.right()` on a `Gfx::Rect` would return the last
column's coordinate still inside the rectangle, or `left + width - 1`.
This is called 'endpoint inclusive' and does not make a lot of sense for
`Gfx::Rect<float>` where a rectangle of width 5 at position (0, 0) would
return 4 as its right side. This same problem exists for `.bottom()`.
This changes `Gfx::Rect` to be endpoint exclusive, which gives us the
nice property that `width = right - left` and `height = bottom - top`.
It enables us to treat `Gfx::Rect<int>` and `Gfx::Rect<float>` exactly
the same.
All users of `Gfx::Rect` have been updated accordingly.
Avoid possible null optional dereference when creating border radius
clipper, and avoid creating clipper if the clip rect is empty (which
prevents some debug spam). Also remove an unnecessary lambda.
This allows the painting subsystem to request a bitmap with the exact
size needed for painting, instead of being limited to "just give me a
bitmap" (which was perfectly enough for raster images, but not for
vector graphics).
This implements the stop-opacity, fill-opacity, and stroke-opacity
properties (in CSS). This replaces the existing more ad-hoc
fill-opacity attribute handling.
After finishing layout, iframe layout boxes (FrameBox) get notified
about their new size by LayoutState::commit(). This information is
forwarded to the nested browsing context, where it can be used for
layout of the nested document.
The problem here was that we notified the FrameBox twice. Once when
assigning the used offset to its paintable, and once when assigning its
size. Because the offset was assigned first, we ended up telling the
FrameBox "btw, your size is 0x0". This caused us to throw away all
the layout information we had for the nested document.
We'd then say "actually, your size is 300x200" (or something) but by
then it was already too late, and we had to do a full relayout.
This caused iframes to flicker as every time their containing document
was laid out, we'd nuke the iframe layout and redo it (on a zero timer).
The fix is pleasantly simple: we didn't need to inform the nested
document of its offset in the containing document's layout anyway. Only
its size is relevant. So we can simply remove the first call, which
removes the bogus 0x0 temporary size.
Note that iframes may still flicker if they change size in the
containing document. That's a separate issue that will require more
finesse to solve. However, this fixes a very noticeable common case.
We achieve this by adding a new Layout::ImageProvider class and having
both HTMLImageElement and HTMLObjectElement inherit from it.
The HTML spec is vague on how object image loading should work, which
is why this first pass is focusing on image elements.
Previously, Frames could set both these properties along with a
thickness to confusing effect: Most shapes of the same shadowing only
differentiated at a thickness >= 2, and some not at all. This led
to a lot of creative but ultimately superfluous choices in the code.
Instead let's streamline our options, automate thickness, and get
the right look without so much guesswork.
Plain shadowing has been consolidated into a single Plain style,
and 0 thickness can be had by setting style to NoFrame.
This bit is mostly ad-hoc for now. This simply turns fill: url(#grad1)
into document().get_element_by_id('grad1') then resolves the gradient.
This seems to do the trick for most use cases, but this is not
attempting to follow the spec yet to keep things simple.
This will be needed by the layout node, which may change what is painted
when the position of the frame image is not the same as the element's
current time.
