This commit un-deprecates DeprecatedString, and repurposes it as a byte
string.
As the null state has already been removed, there are no other
particularly hairy blockers in repurposing this type as a byte string
(what it _really_ is).
This commit is auto-generated:
$ xs=$(ack -l \bDeprecatedString\b\|deprecated_string AK Userland \
Meta Ports Ladybird Tests Kernel)
$ perl -pie 's/\bDeprecatedString\b/ByteString/g;
s/deprecated_string/byte_string/g' $xs
$ clang-format --style=file -i \
$(git diff --name-only | grep \.cpp\|\.h)
$ gn format $(git ls-files '*.gn' '*.gni')
Previously, we determined the positions of glyphs for each text run at
the time of painting, which constituted a significant portion of the
painting process according to profiles. However, since we already go
through each glyph to figure out the width of each fragment during
layout, we can simultaneously gather data about the position of each
glyph in the layout phase and utilize this information in the painting
phase.
I had to update expectations for a couple of reference tests. These
updates are due to the fact that we now measure glyph positions during
layout using a 1x font, and then linearly scale each glyph's position
to device pixels during painting. This approach should be acceptable,
considering we measure a fragment's width and height with an unscaled
font during layout.
This change separates a part of the `draw_text_run()` function, which
is responsible for calculating the positions for glyphs that need to be
painted, into a separate function called `get_glyph_run()`.
It is a part of the preparation for text run painting using OpenGL,
where we can't immediately blit glyph bitmaps but instead need to
prepare a sequence of quads for them in advance.
Currently, we compute the width of text one code point at a time. This
ignores grapheme clusters (emoji in particular). One effect of this is
when highlighting a multi-code point emoji. We will errantly increase
the highlight rect to the sum of all code point widths, rather than
just the width of the resolved emoji bitmap.
This is achieved by simplifying the logic in TextLayout. We get rid
of all the various ways that the layout bounding rect can get cropped.
Then we make sure to use the right pixel metrics.
Finally we use the font's own line gap metrics instead of hard-coding 4.
The end result is that text painted with vector fonts now gets pretty
reasonable vertical alignment in most cases.
This will make it easier to support both string types at the same time
while we convert code, and tracking down remaining uses.
One big exception is Value::to_string() in LibJS, where the name is
dictated by the ToString AO.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).
No functional changes.
This was previously required because the whitespace was consumed and
manually added back after the fact, but now that we preserve whitespace,
this breaks wrapping of text with whitespace after it.
This converts the TextLayout algorithm from handling just words to
handling blocks of strings. With this model, whitespace is preserved
and inserted as-is, rather than being eaten and then replaced with a
single space (or none, if the whitespace was at the start of the word).
Closes#9032.
This class now contains all the fun bits about laying out text in a
rect. It will handle line wrapping at a certain width, cutting off lines
that don't fit the given rect, and handling text elision.
Painter::draw_text now internally uses this.
Future work here would be not laying out text twice (once actually
preparing the lines to be rendered and once to get the bounding box),
and possibly adding left elision if necessary.
Additionally, this commit makes the Utf32View versions of
Painter::draw_text convert to Utf8View internally. The intention is to
completely remove those versions, but they're kept at the moment to keep
the scope of this PR small.