Reduction of bug:
```html
<!DOCTYPE html><style>
html {
overflow-x: hidden;
overflow-y: scroll;
}
div {
background: orange;
height: 1000px;
width: 500px;
}
</style><body><div>
```
Fixes https://github.com/SerenityOS/serenity/issues/21690 and painting
on many other websites (null.com, servo.org).
Representing a text run panting command as a vector of glyphs, rather
than as a string simplifies collecting of unique glyphs which is a
prerequisite for `prepare_glyphs_texture()` call.
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.
In the upcoming changes, Painter will be used to store the state of
OpenGL context. For example, if Painter is aware of the shader that
have already been loaded, it will be possible to reuse them across
repaints. Also, it would be possible to manage state of loaded textures
and add/remove them depending on which ones are present in the next
sequence of painting commands.
Previously we didn't always set the bitmap_intersect correctly when
applying an object-position. This lead to images not correctly being
centered when the axis that it should move along was not the specified
axis.
Previously, all SVG <text> elements were zero-sized boxes, that were
only actually positioned and sized during painting. This led to a number
of problems, the most visible of which being that text could not be
scaled based on the viewBox.
Which this patch, <text> elements get a correctly sized layout box,
that can be hit-tested and respects the SVG viewBox.
To share code with SVGGeometryElement's the PathData (from the prior
commit) has been split into a computed path and computed transforms.
The computed path is specific to geometry elements, but the computed
transforms are shared between all SVG graphics elements.
This removes the awkward hack to recompute the layout transform at paint
time, and makes it possible for path sizes to be computed during layout.
For example, it's possible to use relative units in SVG shapes (e.g.
<rect>), which can be resolved during layout, but would be hard to
resolve again during painting.
The postitioning enum values are used by the position CSS property.
Unfortunately, the prior naming clashes with the CSS Values-4 type
named position, which will be implemented in a later commit.
This change makes RecordingPainter to emit a FillRect command instead
of FillRectWithRoundedCorners if all corners have a radius = 0.
`fill_rect_with_rounded_corners()` in LibGfx already has a similar
optimization. But now when we also have LibAccelGfx, which does not
support painting rectangles with rounded corners yet, it makes sense to
emit FillRect whenever possible.
After 4318bcf447 RecordingPainter
is suppoed to write commands in coordinate system of stacking context.
This commit adds missing translation for FillRect command.
Fixes regression introduced in 4318bcf447
`shadow_bounding_rect` is used on bitmap allocated for shadow and is
not supposed to be in coordinate system of stacking context. Same for
`text_rect`.
Fixes https://github.com/SerenityOS/serenity/issues/21587
Removing State and Restore reduces painting commands count by 30-50%
on an average website.
Due to this change, it was also necessary to replace AddClipRect with
SetClipRect command.
By storing painting command coordinates relative to the nearest
stacking context we can get rid of the Translate command.
Additionally, this allows us to easily check if the bounding
rectangles of the commands cover or intersect within a stacking
context. This should be useful if we decide to optimize by avoiding
the execution of commands that will be overpainted by the results of
subsequent commands.
With the recording painter the actual painting operations are delayed,
so now if multiple corner clippers are constructed, and they use a
shared bitmap they can interfere with each other. The use of this shared
bitmap was somewhat questionable anyway, so this is not much of a loss.
This fixes the border-radius.html test page.
This change separates the box outer shadow metrics calculations into a
separate function. This function is then used to obtain the shadow
bounding rectangle and skip painting if the entire shadow is outside
of the viewport.
This modification introduces a new layer to the painting process. The
stacking context traversal no longer immediately calls the
Gfx::Painter methods. Instead, it writes serialized painting commands
into newly introduced RecordingPainter. Created list of commands is
executed later to produce resulting bitmap.
Producing painting command list will make it easier to add new
optimizations:
- It's simpler to check if the painting result is not visible in the
viewport at the command level rather than during stacking context
traversal.
- Run painting in a separate thread. The painting thread can process
serialized painting commands, while the main thread can work on the
next paintable tree and safely invalidate the previous one.
- As we consider GPU-accelerated painting support, it would be easier
to back each painting command rather than constructing an alternative
for the entire Gfx::Painter API.
This commit removes DeprecatedString's "null" state, and replaces all
its users with one of the following:
- A normal, empty DeprecatedString
- Optional<DeprecatedString>
Note that null states of DeprecatedFlyString/StringView/etc are *not*
affected by this commit. However, DeprecatedString::empty() is now
considered equal to a null StringView.
Instead of resolving lengths used in the backdrop-filter during
painting, we can do that earlier in apply_style().
This change moves us a bit closer to the point when the stacking
context tree will be completely separated from the layout tree :)
This allows applying SVG <mask>s to elements. It is only implemented for
the simplest (and default) case:
- mask-type = luminance
- maskContentUnits = maskContentUnits
- maskUnits = objectBoundingBox
- Default masking area
It should be possible to extend to cover more cases. Though the layout
for maskContentUnits = objectBoundingBox will be tricky to figure out.
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 fixes an issue where the value would be out of sync with reality
in anonymous wrapper block boxes, since we forgot to compute m_visible
after assigning the computed values to them.
Fixes#21106
d06d4eb made the `clip` property apply to children of an absolute-
positioned element, but caused it not to be applied to the element the
property was applied to directly.
To fix this, apply the clip in new `before_paint()` and `after_paint()`
functions. Doing so keeps painter state from leaking from `paint()`,
but still allows subclasses of `PaintableBox` clip their contents
correctly without repeating the application of the clip rectangle.
