This allows SVG mask elements to have layout computed, but not connected
to the main paint tree. They should only be reachable if (and painted)
if referenced by the "mask" attribute of another element.
This is controlled by the forms_unconnected_subtree() function on the
paintable, which (if it returns true) prevents the paintable from being
added as a child to what would be its parent.
This doesn't seem to actually have fixed any bugs, as having
FillOpacity instead of StrokeOpacity in the call to parse_css_value
doesn't seem to have actually been causing bugs. But, I still think it's
worthwhile correcting.
The reason that it wasn't causing bugs is that having FillOpacity
instead of StrokeOpacity in the call to parse_css_value means that when
parsing the value is compared to the acceptable values for that property
(for example the value can only be a percentage, or a number, etc.). In
this case both FillOpacity and StrokeOpacity seem to accept the same
values.
The SVG G container should have the same size as its children. This
fixes a bug when there was an opacity value on the G element, as in
StackingContext it would try and get a bitmap of the element which would
be empty due to it having no size.
Return error when input svg is not valid and SVGSVGElement is not
present in the tree instead of doing svg_root nullptr dereference.
Fixes crash on https://apps.kde.org/en-gb/
The fix here has two parts:
1. Don't use the fallback viewBox at all if we're not in SVG-as-image.
2. Don't make a fallback viewBox with zero width and/or height.
This fixes a crash on Bandcamp pages. Thanks Tim Flynn for reporting!
When embedding an SVG in an img element, if the external SVG's root
element has both width and height attributes, but no viewBox attribute,
we now create a fallback viewBox with "0 0 width height".
This appears to match the behavior of other browsers. Inspired by
discussion on Mozilla's bug tracker:
https://bugzilla.mozilla.org/show_bug.cgi?id=614649
The spec says the result of this algorithm is undefined in such cases,
and it appears that other engines yield a zero size.
More importantly, this prevents us from leaking a non-finite value into
the layout tree.
This was crashing on google.com with the linux chrome user agent,
interestingly it seems like this behavior may have been accidental as
only two of the three `parse_number()` were changed in f7dbcb6
SVG presentation attributes are parsed as CSS values, so we also need to
handle CSS variable expansion when handling them.
This (roughly) matches the behavior of other engines. It's also used on
the web, for example on https://stripe.com/ :^)
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).
This is far from perfect, but let's at least make an attempt at laying
out <svg> when encountering it inside another <svg>.
This makes https://awesomekling.substack.com actually load and render
instead of asserting. :^)
Per SVG2, any coordinate pairs following a moveto command should be
treated as implicit lineto commands with the same absoluteness as the
moveto command.
