This change fixes a problem that we should not call `to_px()` to
resolve any length or percentage values during paintables traversal
because that is supposed to happen while performing layout.
Also it improves performance because before we were resolving border
radii during each painting phase but now it happens only once during
layout.
Currently, in CPU painter, border painting is implemented by building
a Gfx::Path that is filled by Gfx::AntiAliasingPainter. In the GPU
painter, we will likely want to do something different, and with a
special command, it becomes possible.
Also, by making this change, the CPU executor also benefits because now
we can skip building paths for borders that are out of the viewport.
By consistently accepting only device pixel values instead of a mix of
CSSPixels and DevicePixels values, we can simplify the implementation
of paint_border() and paint_all_borders().
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 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 function is used to calculate a matching radius that goes inside or
outside of the border. For example, if the border-radius is 10px and we
are 5px further out, the radius needs to be 15px to look right.
However, if the radius is 0 it isn't rounded, and we want to keep the
same sharp corner no matter how far we go.
This makes our outline rendering better match Chrome and Firefox.
Build a grid snapped to device pixels and use it to construct the
rectangles for the cell edges, same as for collapsed borders. This is
especially important when border-spacing is set to 0 since it avoids
gaps between adjacent cells which have borders set.
...along with `outline-color`, `outline-style`, and `outline-width`.
This re-uses the existing border-painting code, which seems to work well
enough!
This replaces the previous code for drawing focus-outlines, with generic
outline painting for any elements that want it. Focus outlines are now
instead supported by this code in Default.css:
```css
:focus-visible {
outline: auto;
}
```
The refactor of the border painting mainly to handle:
1. Single border with minor border radius.
2. Different border widths and border colors joined situations.
This refactor only apply to solid border.
The main differece is to use Path.fill to paint each border,
not fill_rect anymore. There's a special case need to consider.
The Path.fill will leave shared edge blank between two borders.
To handle this, we decide to combine the borders with same color
to paint together.
This commit reimplements the (normally) 45 degree (depends on
the widths) connection between to adjacent borders. Which is
needed to paint the 'caret' icon seen in a few buttons on GitHub.
The issue of overlapping pixels while painting this has also
been solved for the 45 degree case (the the most likely case,
the other cases only occur of mixed-with borders).
This commit adds some much nicer border painting, which now supports:
- Elliptical corners
- Blending between different border thicknesses, with rounded corners
- Anti-aliasing
There are some little TODOs left to tackle:
- Painting the corners with line styles other than solid
- Blending between colors on the corners (see comments)
The painting requires allocating a small bitmap, that only fits the
corners (so in most cases this is very small).
This bitmap is then cached so for all paints but the first there will
be no further allocations.
The logic here is needed by InlineNode too. Moving it into a
`paint_all_borders()` function makes it available to them both, as well
as anyone else who wants it. :^)
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
