* Closes https://github.com/emilk/egui/issues/3816

Turn off with `style.interaction.multi_widget_text_select`.
There is an API for this in `LabelSelectionState`, but it's pretty
bare-bones.
This became really hairy implementation-wise, but it works decently
well.
# Limitations
* Drag-select to scroll doesn't work
* A selection disappears if you scroll past one of its end-points
* Only the text of labels and links are selectable
## TODO
* [x] An option to turn it off
* [x] An API for querying about the selected text, and to deselect it.
* [x] Scrolling past selection behaves weird
* [x] Shift-click to select a range
* Closes https://github.com/emilk/egui/issues/3804
Add ability to select the text in labels with mouse-drag, double-click,
and keyboard (once clicked).
Hit Cmd+C to copy the text. If everything of a label with elided text is
selected, the copy command will copy the full non-elided text. IME and
accesskit _should_ work, but is untested.
You can control wether or not text in labels is selected globally in
`style.interaction.selectable_labels` or on a per-label basis in
`Label::selectable`. The default is ON.
This also cleans up the `TextEdit` code somewhat, fixing a couple
smaller bugs along the way.
This does _not_ implement selecting text across multiple widgets. Text
selection is only supported within a single `Label`, `TextEdit`, `Link`
or `Hyperlink`.

## TODO
* [x] Test
Apparently the font implementation uses a distance check to decide if
the font(or whatever) need recalculations, after dpi changed:
8d4de866d4/crates/epaint/src/text/fonts.rs (L381-L382)
This leads to warnings when the pixel_per_point diff is very low and
spams the log. (<- this happens for me if i resize my window on kwin,
e.g. maximize it)
(I don't want to debate if the float difference generally makes sense,
so if you want to rework that instead just close this pr)
The ignored characters are used in some custom fonts.
for example: the \u{F0FF} is used as `cleaning_services` in
MaterialIcons-Regular.ttf
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Closes <https://github.com/emilk/egui/issues/THE_RELEVANT_ISSUE>.
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
This introduces a special `Color32::PLACEHOLDER` which, during text
painting, will be replaced with `TextShape::fallback_color`.
The fallback color is mandatory to set in all text painting. Usually
this comes from the current visual style.
This lets users color only parts of a `WidgetText` (using e.g. a
`LayoutJob` or a `Galley`), where the uncolored parts (using
`Color32::PLACEHOLDER`) will be replaced by a default widget color (e.g.
blue for a hyperlink).
For instance, you can color the `⚠️`-emoji red in a piece of text red
and leave the rest of the text uncolored. The color of the rest of the
text will then depend on wether or not you put that text in a label, a
button, or a hyperlink.
Overall this simplifies a lot of complexity in the code but comes with a
few breaking changes:
* `TextShape::new`, `Shape::galley`, and `Painter::galley` now take a
fallback color by argument
* `Shape::galley_with_color` has been deprecated (use `Shape::galley`
instead)
* `Painter::galley_with_color` has been deprecated (use
`Painter::galley` instead)
* `WidgetTextGalley` is gone (use `Arc<Galley>` instead)
* `WidgetTextJob` is gone (use `LayoutJob` instead)
* `RichText::into_text_job` has been replaced with
`RichText::into_layout_job`
* `WidgetText::into_text_job` has been replaced with
`WidgetText::into_layout_job`
* eframe README: explain how to enable copy/paste
* Implement Debug for a couple of structs
* Code cleanup
* Better docs
* profile ron serialization
* CI: Allow "exclude from changelog" as the only label
* Add Row::text
* Rename elide_at_width -> truncate_at_width
* Move text layout tests to own module
* Add test to check that elision character is always included
* Include elision character in more circumstances
* Append overflow character if we can't replace
* Always append … when eliding
* Add a secondary text to the text layout demo
* Silence a few clippy warnings
* Use named threads
* Remove some deprecated functions
* Document Context and Ui fully
* Use `parking_lot::Mutex` in `eframe`
* Expand clippy.toml files
* build fix
* Add `TextFormat::extra_letter_spacing`
* Add control of line height
* Add to text layout demo
* Move the text layout demo to its own window in the demo app
* Fix doclink
* Better document points vs pixels
* Better documentation and code cleanup
* Add option to clip text to wrap width
* Spelling
* Better naming, and report back wether the text was elided
* Improve docstrings
* Simplify
* Fix max_rows with multiple paragraphs
* Add note
* Typos
* fix doclink
* Add `Label::elide`
* Label: show full non-elided text on hover
* Add demo of `Label::elide`
* Call it `Label::truncate`
* Clarify limitations of `break_anywhere`
* Better docstrings
* use font metrics in layout
* properly center scaled fonts
* adjust docs
* fix raised text
* fix easymark viewer small text alignment
caused by variable row heights
* squash before rebase
* Update AccessKit, introducing support for editable spinners on Windows and an important fix for navigation order on macOS
* Restore support for increment and decrement actions in DragValue
* Avoid VoiceOver race condition bug
* fix clippy lint
* Tell AccessKit that the default action for a text edit (equivalent to a click) is to set the focus. This matters to some platform adapters.
* Refactor InputState functions for AccessKit actions
* Support the AccessKit SetValue for DragValue; this is the only way for a Windows AT to programmatically adjust the value
* Same for Slider
* Properly associate the slider label with both the slider and the drag value
* Lazily activate egui's AccessKit support
* fix clippy lint
* Update AccessKit
* More documentation, particularly around lazy activation
* Tweak one of the doc comments
* See if I can get AccessKit exempted from the 'missing backticks' lint
* Make PlatformOutput::accesskit_update an Option
* Refactor lazy activation
* Refactor node mutation (again)
* Eliminate the need for an explicit is_accesskit_active method, at least for now
* Fix doc comment
* More refactoring of tree construction; don't depend on Arc::get_mut
* Override a clippy lint; I seem to have no other choice
* Final planned refactor: a more flexible approach to hierarchy
* Last AccessKit update for this PR; includes an important macOS DPI fix
* Move and document the optional accesskit dependency
* Fix comment typo
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* reformat
* More elegant code for conditionally creating a node
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* Set step to 1.0 for all integer sliders
* Add doc example for Response::labelled_by
* Clarify a TODO comment I left for myself
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* eframe web: Add WebInfo::user_agent
* Deprecate `Modifier::ALT_SHIFT`
* Add code for formatting Modifiers and Key
* Add type KeyboardShortcut
* Code cleanup
* Add Context::os/set_os to query/set what OS egui believes it is on
* Add Fonts::has_glyph(s)
* Add helper function for formatting keyboard shortcuts
* Faster code
* Add way to set a shortcut text on menu buttons
* Cleanup
* format_keyboard_shortcut -> format_shortcut
* Add TODO about supporting more keyboard sumbols
* Modifiers::plus
* Use the new keyboard shortcuts in emark editor demo
* Explain why ALT+SHIFT is a bad modifier combo
* Fix doctest
Closes https://github.com/emilk/egui/issues/2068
Before this PR, the default font, Ubuntu-Light, was ~11% smaller
than it should have been, and the default monospace font, Hack,
was ~14% smaller. This means that setting the font size `12` in egui
would yield smaller text than using that font size in any other app.
Ooops!
The change is that this PR now takes into account the ttf properties
`units_per_em` and `height_unscaled`.
If your egui application has specified you own font sizes or text styles
you will see the text in your application grow
larger, unless you go in and compensate by dividing all font sizes by
~1.21 for Ubuntu-Light/Proportional and ~1.16 for Hack/Monospace,
and with something else if you are using a custom font!
This effects any use of `FontId`, `RichText::size`, etc.
This PR changes the default `Style::text_styles` to compensate,
so the default egui style should look the same before and after this PR.