This change is a reworking of the shaping code and simplification of the
`GlyphRun` data structure.
The shaper was written between 2012 and 2014 against an early version of
Rust. It was originally written to have a single glyph entry per UTF-8
code point. This is useful when you always need to iterate through
glyphs based on UTF-8 code points. Unfortunately, this required a
tri-level data structure to hold detailed glyphs and meant that CJK
characters took over 3x the memory usage of ASCII characters. In
addition, iterating through glyphs (the most common and basic operation
on shaped text) required doing a lookup involving a binary search for
detailed glyphs (ones that had large advances or mapped to more or less
than a single UTF-8 code point).
The new design of the `GlyphStore` is instead based on `chars` in the
input string. These are tracked during layout so that the resulting
glyph output can be interpreted relatively to its original character
offset in the containing IFC. We are already dealing with IFC text on a
per-character basis for a variety of reasons (such as text
transformation and whitespace collapse). In addition, we will now able
to
implement mapping between the character offsets before and after layout
transformations of the original DOM string.
Now the penalty of more complex glyph iteration is only paid when
transforming glyph offsets to character offsets. Currently this is only
done for selections and clicking in text boxes, both of which are much
less common than layout.
This change does not properly handle selections in RTL text, though
rendering and basic selection and visual movement works (though buggy).
It does not seem like this affects the performance of shaping based on
measurement using the text shaping performance counters. This likely
means that the performance of shaping is dominated on our machines by
HarfBuzz. We noticed no performance degradation in Speedometer when run
on a M3 Mac.
Followup work:
- Properly handle selection in RTL text.
- Support mapping from original DOM character offsets to offsets in
layout after text transformation and whitespace collapse. This is now
possible.
Testing: This causes some tests to pass and a few to fail. This is
likely
due to the fact that we are handling glyphs more consistently while
shaping. Of the new failures:
- `letter-spacing-bengali-yaphala-001.html`,
`letter-spacing-cursive-001.html`, `font-feature-settings-tibetan.html`
where passing before probably because we were not applying letter
spacing to detailed glyphs. These scripts should not have letter spacing
applied to them, because they are cursive -- which we never implemented
properly. It will be handled in a a followup.
- `shaping-arabic-diacritics-001.html`: This was a false pass. The tests
verifies that Arabic diacritics are applied to NBSP. This wasn't
happening before nor after this change, but the results matched anyway.
Now they don't, but before and after are equally broken.
-
Fixes: #216
Part of #35540.
---------
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This change adds basic support for selecting text via dragging the mouse
in text inputs. This is currently handled entirely inside of text
inputs, but will be integrated into a more global drag handler when that
is implemented in the `DocumentEventHandler`. This means that events
that happen outside of the text input currently don't update the
selection.
Testing: This adds Servo-specific WPT-style tests. There are WPT tests
that test this sort of behavior, but I believe they rely on selection
events, which we have no implemented yet (we will soon).
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Instead of handling selection in text input during box tree / fragment
tree construction, fully handle it during display list construction.
This means that when the selection changes in script, it updates
automatically in the `FragmentTree` and only a new display list is
necessary. This avoids a layout while changing the selection in text
fields.
Testing: This fixes a few rendering issues, but these are very hard
to isolate and test for. It causes one test to start failing, but this
is
because a cursor that wasn't rendered properly now starts showing
up.
Fixes: #41920.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
In text inputs, the edit point can be equal to a non-`None` selection
origin for a variety of reasons such as when the selection is set by a
DOM API or when a composition event inserts a zero length string. In
both of these cases, we should treat the selection as collapsed. It is
important to do this because for the purposes of arrow key movement and
context menu entries, we should think of the text input as not having a
selection at all.
Testing: This change adds a Servo-specific WPT test, as key press
behavior is
platform specific.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This constructors takes more arguments than it needs to. The three
arguments removed are almost always the default values. The exception is
in the unit tests. In this change those calls are modified to use
`set_max_length` like is done in the actual script code.
Testing: This is just a simplification of the code, so should be covered
by existing tests.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This change adds support for updating the selection when double and
triple clicking in text fields. Double clicking selects the most
relevant word while triple clicking selects the entire line.
Testing: This change adds unit tests for `Rope` as well as a
Servo-specific WPT style test. These behaviors are platform
dependent.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This change moves all single versus multiline input handling to script.
It didn't really belong in `Rope`. In addition, it ensures that all
insertions into single line text boxes are sanitized by replacing
linebreaks with spaces.
Testing: As pasting is hard to test with a WPT-style test, this changes
includes new unit tests.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This change updates and implements the old `query_text_index` layout
query to properly look for the glyph index of a point within a node's
`Fragment`s. This should work properly with the shadow DOM of both
`<input>` and `<textarea>` elements. In particular, multiple lines are
supported.
Caveats:
- `<input>` and `<textarea>` that are transformed are currently not
supported. This will happen in a followup.
- For multi-line inputs, we should be finding the text offset of the
nearest line that is within the block range of the click. This will
happen in a followup.
Testing: This change adds two Servo-specific WPT-style tests. These are
Servo-specific because the behavior of clicking in text fields isn't
fully specified.
Fixes: #35432Fixes: #10083
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Josh Matthews <josh@joshmatthews.net>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This change makes it so that all form controls are implemented with
shadow DOM, completely removing the legacy text content and selection
code paths for form controls. The motivation for this change is:
- to allow properly hit testing against the text nodes of `<textarea>`
and other widgets. This is important for implementing mouse-based
selection on the page.
- to simplify the way that form controls are implemented in general and
to prepare the way for proper implementations of the user interface of
other controls.
Testing: This should not change observable behavior at the moment,so
should be covered by existing WPT tests.
---------
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
`TextInput` internally stores a rope of text content, one segment for
each line. This change separates out the rope into a separate `Rope`
data structure that can be shared with other parts of Servo.
`TextInput` needs to move through text content in a variety of ways,
depending on the keys pressed when interacting with a text area. This
change provides a unified movement API in both `Rope` and in
`TextInput` ensuring that selection is handled consistently (apart from
a few minor quirks [^1]). This simplifies the code an improves
interactive behavior.
[^1]: One of these quirks is that the edit point will move to
directional end of the motion when collapsing a selection, but only when
moving by grapheme or word (and not by line). These quirks existed in an
undocumented way previously and they are preserved with code comments.
Testing: This is covered by existing unit tests (updated for the new
API) and
the WPT suite.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
DOM APIs for interacting with selection and text in text inputs
`<input type=text>` and `<textarea>` all accept offsets and lengths in
UTF-16 code units. Servo was not converting all of these offsets into
UTF-8 code units. This change makes it so that this conversion is done
more thoroughly and makes it clear when the code is dealing with UTF-8
offsets and UTF-16 offsets.
Helper functions are added for doing this conversion in both directions
as it is necessary. In addition, a `char` iterator is added for
`TextInput` as it is useful for doing this conversion. It will be used
more completely in the future when a `Rope` data structure is extracted
from `TextInput`.
Finally, specification text is added to all of the DOM implementation
touched here.
Testing: This change includes a new WPT crash test as well as a series
of unit
tests to verify conversion between UTF-8 and UTF-16 offsets.
Fixes#36719.
Fixes#20028.
Fixes#39184.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This moves the Unicode offset types to the `base` crate and makes them
generally more usable throughout the Servo codebase. In addition, they
are renamed to use Rust naming and to be a bit more consistent:
- `UTF8Bytes` -> `Utf8CodeUnitLength`
- `UTF16CodeUnits` -> `Utf16CodeUnitLength`
There is also a bit more documentation explaining their use.
This is preparation for fixing issues with UTF-16 offsets in editable
text fields.
Testing: This does not change behavior so existing WPT tests should
suffice.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
When for example changing the hover state of an element, we were
dirtying it with ContentOrHeritage damage, which forced it to be laid
out again.
This was added in #39102 in order to fix#38989, but for the most part
it's no longer needed.
However, we will now dirty when a `<textarea>` or `<input>` which can be
selected gets or loses focus. This is to ensure that the caret or
selections get correctly updated.
Testing: Manually tested that #38989 is not regressing
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Add context menu options for images, links, and editable text areas. In
addition add the ability to show menu options that are disabled. This
also improves the visual style of the context menu in egui as part of
supporting disabled options.
Testing: This has been manually tested, but we could we should be able
to
easily add unit tests when enriching the API with information about the
active element under context menus.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
For some specific cases (one of them see below) where are requirement to
identify the reason of the attribute mutation (by whom/why it was
changed - by cloning, parser or directly), so the following `reason`
parameter was added to `AttributeMutation::Set` option.
Note that for the HTMLMediaElement the internal `muted` state should be
set to true when the element is created and the element has a `muted`
content attribute specified (should be done once on the first attribute
mutation caused by parser or cloning).
See https://html.spec.whatwg.org/multipage/#dom-media-muted
Testing: Improvements in the following tests
-
html/semantics/embedded-content/media-elements/user-interface/muted.html
Signed-off-by: Andrei Volykhin <andrei.volykhin@gmail.com>
Use `InputEvent` for text input and set appropriate values for the
`composed`, `data`, `isComposing`, and `inputType` attributes. Use a
placeholder for `dataTransfer` attribute and `getTargetRanges` function,
as they are only applicable to contenteditable, which isn't implemented.
Testing: I added two tests under `tests/wpt/mozilla/tests/input-events`
based on the similarly named ones for contenteditable under
`tests/wpt/tests/input-events`.
Fixes: https://github.com/servo/servo/issues/36398
---------
Signed-off-by: Excitable Snowball <excitablesnowball@gmail.com>
This PR adds context menu support with clickable menu items in the
Minibrowser. The menu appears on right click and supports basic
navigation actions (Back, Forward, Reload).
Testing: We already have tests for ContextMenu in WebView API test.
Signed-off-by: atbrakhi <atbrakhi@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Removes some unneeded lints, especially `#[allow(unsafe_code)]`.
Testing: Refactor
Part of: #40383
Signed-off-by: WaterWhisperer <waterwhisperer24@qq.com>
Servo has a lot of comments like this:
```rust
// https://example-spec.com/#do-the-thing
fn do_the_thing() {}
```
and I keep turning these into doc comments whenever I'm working close to
one of them. Doing so allows me to hover over a function call in an IDE
and open its specification without having to jump to the function
definition first. This change fixes all of these comments at once.
This was done using `find components -name '*.rs' -exec perl -i -0777
-pe 's|^([ \t]*)// (https?://.*)\n\1(fn )|\1/// <$2>\n\1$3|mg' {} +`.
Note that these comments should be doc comments even within trait `impl`
blocks, because rustdoc will use them as fallback documentation when the
method definition on the trait does not have documentation.
Testing: Comments only, no testing required
Preparation for https://github.com/servo/servo/pull/39552
---------
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
script: add CanGc as argument to VirtualMethods::children_changed
Testing: These changes do not require tests because they are a refactor.
Addresses part of https://github.com/servo/servo/issues/34573
Signed-off-by: Yerkebulan Tulibergenov <yerkebulan@gmail.com>
Input methods are very similar to other kinds of embedder controls such
as file selection boxes, so merge them into the same libservo API. This
simplfiies the API surface a bit.
Testing: This change comes with a new unit test.
---------
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This implements LazyDOMString (from now on DOMString) as outlined in
https://github.com/servo/servo/issues/39479.
Constructing from a *mut JSString we keep the in a
RootedTraceableBox<Heap<*mut JSString>> and transform
the string into a rust string if necessary via the `make_rust_string`
method.
Methods used in script are implemented on this string. Currently we
transform the string at all times.
But in the future more efficient implementations are possible.
We implement the safety critical sections in a separate module
DOMStringInner which allows simple constructors, `make_rust_string` and
the `bytes` method.
This method returns the new type `EncodedBytes` which contains the
reference to the underlying string in either format.
Testing: WPT tests still seem to work, so this should test this
functionality.
---------
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
This is part of the future work of implementing LazyDOMString as
outlined in https://github.com/servo/servo/issues/39479.
We use str() method or direct implementations on DOMString for these
methods. We also change some types.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
Testing: This is essentially just renaming a method and a type and
should not change functionality.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
This PR **removes** `ScriptToConstellationMessage::ForwardToEmbedder`,
and replaces it with an explicit `ScriptToEmbedderChannel`. This new
channel is based on `GenericCallback` and in single-process mode will
directly send the message the to the embedder and wake it. In
multi-process mode, the message is routed via the ROUTER, since waking
is only possible from the same process currently. This means in
multi-process mode there are likely no direct perf benefits, since we
still need to hop the message over the ROUTER (instead of over the
constellation).
In single-process mode we can directly send the message to the embedder,
which should provide a noticable latency improvement in all cases where
script is blocked waiting on the embedder to reply.
This does not change the way the embedder receives messages - the
receiving end is unchanged.
## How was sending messages to the embedder working before?
1. Script wraps it's message to the embedder in
`ScriptToConstellationMessage::ForwardToEmbedder` and sends it to
constellation.
2. The [constellation event loop] receives the message in
[handle_request]
3. If deserialization fails, [an error is logged and the message is
ignored]
4. Since our message came from script, it is handle in
[handle_request_from_script]
5. The message is logged with trace log level
6. If the pipeline is closed, [a warning is logged and the message
ignored]
7. The wrapped `EmbedderMsg` [is forwarded to the embedder]. Sending the
message also invokes `wake()` on the embedder eventloop waker.
[constellation event loop]:
2e1b2e7260/components/constellation/constellation.rs (L755)
[handle request]:
2e1b2e7260/components/constellation/constellation.rs (L1182)
[an error is logged and the message is ignored]:
2e1b2e7260/components/constellation/constellation.rs (L1252)
[handle_request_from_script]:
https://github.com/servo/servo/blob/main/components/constellation/constellation.rs#L1590
[a warning is logged and the message ignored]:
2e1b2e7260/components/constellation/constellation.rs (L1599)
[is forwarded to the embedder]:
2e1b2e7260/components/constellation/constellation.rs (L1701)
Testing: Communication between Script and Embedder is extensive, so this
should be covered by existing tests.
Signed-off-by: Jonathan Schwender <schwenderjonathan@gmail.com>
