This makes use of the new Gfx::Path::text() to handle SVG text elements,
with this text is just a regular path, and can be manipulated like any
other graphics element.
This removes the SVGTextPaintable and makes both <text> and geometry
elements use a new (shared) SVGPathPaintable. This is identical to the
old SVGGeometryPaintable. This simplifies painting as once something is
resolved to a Gfx::Path, the painting logic is the same.
This patch just adds the new root paintable and updates the tests
expectations. The next patch will move painting logic from the layout
viewport to the paint viewport.
Using fixed-point saturated arithmetics for CSSPixels allows to avoid
accumulating floating-point errors.
This implementation is not complete yet: currently saturated
arithmetics implemented only for addition. But it is enough to not
regress any of layout tests we have :)
See https://github.com/SerenityOS/serenity/issues/18566
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.
There are a couple of things that went into this:
- We now calculate the intrinsic width/height and aspect ratio of <svg>
elements based on the spec algorithm instead of our previous ad-hoc
guesswork solution.
- Replaced elements with automatic size and intrinsic aspect ratio but
no intrinsic dimensions are now sized with the stretch-fit width
formula.
- We take care to assign both used width and used height to <svg>
elements before running their SVG formatting contexts. This ensures
that the inside SVG content is laid out with knowledge of its
viewport geometry.
- We avoid infinite recursion in tentative_height_for_replaced_element()
by using the already-calculated used width instead of calling the
function that calculates the used width (since that may call us right
back again).
