Follows the same approach as #8261: replaces Ubuntu-Light with a
variable font hinted via ttfautohint, updates fallback references,
loosens a couple of tests that hard-coded font-specific pixel values,
and regenerates all visual snapshots.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
<!--
Please read the "Making a PR" section of
[`CONTRIBUTING.md`](https://github.com/emilk/egui/blob/main/CONTRIBUTING.md)
before opening a Pull Request!
* Keep your PR:s small and focused.
* The PR title is what ends up in the changelog, so make it descriptive!
* If applicable, add a screenshot or gif.
* If it is a non-trivial addition, consider adding a demo for it to
`egui_demo_lib`, or a new example.
* Do NOT open PR:s from your `master` branch, as that makes it hard for
maintainers to test and add commits to your PR.
* Remember to run `cargo fmt` and `cargo clippy`.
* Open the PR as a draft until you have self-reviewed it and run
`./scripts/check.sh`.
* When you have addressed a PR comment, mark it as resolved.
Please be patient! I will review your PR, but my time is limited!
-->
# What it does
Addition of a new system of theme plugins which allow the user to use
different rules engine to compute the style for the available
specialised widget style.
# How to use
Create a engine implementing the trait `ThemePlugin` and `ThemeStyle<S:
StyleStruct>` and implement the necessary methods, then register this
way (example for `ButtonStyle`):
```ui.add_theme::<ButtonStyle>(&mycustomengine);```
Now all button will call the `ThemeStyle<ButtonStyle>` method to compute the correct style and later use the cached value to avoid the costly computation.
If no valid `ThemeStyle<S>` or engine is available then it fallback to the default style.
* Closes part of <https://github.com/emilk/egui/issues/3284>
* [x] I have followed the instructions in the PR template
---------
Co-authored-by: adrien <221212@umons.ac.be>
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Lucas Meurer <hi@lucasmerlin.me>
The Debug-formatting of `Id` in debug-builds now contain the full
lineage:
```rs
#[test]
fn with_chain() {
let id = Id::new("a").with("b").with("c").with(7_i32);
assert_eq!(
format!("{id:?}"),
r#"Id::new("a").with("b").with("c").with(7)"#
);
}
```
## Related
* https://github.com/emilk/egui/pull/5851
* https://github.com/emilk/egui/pull/7988
<!--
Please read the "Making a PR" section of
[`CONTRIBUTING.md`](https://github.com/emilk/egui/blob/main/CONTRIBUTING.md)
before opening a Pull Request!
* Keep your PR:s small and focused.
* The PR title is what ends up in the changelog, so make it descriptive!
* If applicable, add a screenshot or gif.
* If it is a non-trivial addition, consider adding a demo for it to
`egui_demo_lib`, or a new example.
* Do NOT open PR:s from your `master` branch, as that makes it hard for
maintainers to test and add commits to your PR.
* Remember to run `cargo fmt` and `cargo clippy`.
* Open the PR as a draft until you have self-reviewed it and run
`./scripts/check.sh`.
* When you have addressed a PR comment, mark it as resolved.
Please be patient! I will review your PR, but my time is limited!
-->
* [x] I have followed the instructions in the PR template
At low apha values, premultiplied colors lose precision.
This PR makes the color picker use unmultiplied colors internally.
Before:
https://github.com/user-attachments/assets/4617a355-daa9-4911-86e6-518ac6867014
After:
https://github.com/user-attachments/assets/d9681b01-50d8-418e-b5a5-79b4bd1bbddf
* Closes https://github.com/emilk/egui/pull/7254
You can now drag-to-close a panel. Also drag-to-expand panels.
This is a breaking change: the animated panel functions now take a
`open: &mut bool` instead of `open: bool`.
This is only enabled for resizable panels
## Related
* https://github.com/emilk/egui/pull/5851
* https://github.com/emilk/egui/pull/7988
## What
We want to make it easier to understand the lineage of a `Id` (which is
the parent `Id`, and the parent of that, etc?)
As a first step of that, we want to clarify the different between a
globally unique `Id`, and an `IdSalt`
I also introduced the `AsId` and `AsIdSalt` traits, which are
implemented of anything that implements `Hash` and `Debug`. The `Debug`
half of that is unused here, but will later be used in `Debug` builds to
produce a proper tree.
* Part of https://github.com/emilk/egui/issues/8180
So far, you've been able to move any `egui::Window` by dragging anywhere
on it. This makes sense on touch screens with thick fingers, but less so
on non-touch-screens.
With this PR, you can now control it with a new enum `WindowDrag`
* part of #7264
* based on https://github.com/emilk/egui/pull/8152
The resize fix allows use to really simplify how the Window Titlebar is
rendered. Previously it was using some complex flow to calculate and
allocate the height first and then render it later once we knew the
windows final width.
Since now windows can't shrink past their minimum content widths, I can
just show the titlebar inline with the regular content, just outside of
the `Resize` container so that it is always visible.
This does change what the size of a window means. Before, size was just
the size of the contents, while now size (e.g. via min_height) will
include the Frames margin and outline, title bar and the contents.
Also, the window label now truncates as you shrink the window (meaning
windows can now be smaller than their label allows).
---------
Co-authored-by: lucasmerlin <8009393+lucasmerlin@users.noreply.github.com>
A couple improvements to centered and right-aligned text edits:
- Fix text selection in centered and right aligned text edits
(ironically, this broke in #8076)
- Fix cursor movement in centered and right aligned text edits
(horizontal cursor position will be retained on vertical movement)
- Multiline text edit exceeding available width if there are atoms
- Added atoms & alignment options to text edit demo
- Improve how vertical_align and horizontal_align are applied
- Textedit atom is grow now, removing the need for the extra seperate
grow atom
- This allows us to apply the `align` on the text edit atom instead of
the whole AtomLayout
- Fixes https://github.com/emilk/egui/pull/8022
- Fixes https://github.com/emilk/egui/issues/7999
* Related to #56 (Improve text — tracking issue)
## Summary
This PR integrates [harfrust](https://crates.io/crates/harfrust) (a
pure-Rust port of HarfBuzz) into epaint's text layout pipeline,
replacing the character-by-character glyph positioning with proper
OpenType text shaping.
### What this enables
- **GPOS kerning**: most modern fonts only ship kerning in GPOS tables
(not the legacy `kern` table). Pairs like "AV", "VA", "AT" are now
properly tightened.
- **GSUB substitutions**: ligatures (fi, fl), contextual alternates, and
other OpenType features.
- **Combining marks**: diacritics (e.g. ɔ̃) are positioned via anchor
tables instead of being rendered as standalone replacement glyphs.
### Before/After
#### Kerning, etc.
<img width="838" height="726" alt="before_main"
src="https://github.com/user-attachments/assets/f0f26d5f-b117-43a6-b39c-ea40d2e73836"
/>
<img width="838" height="726" alt="after_harfrust"
src="https://github.com/user-attachments/assets/d983e5da-486c-4f39-bd4f-5782a90c6b39"
/>
#### Ligatures
<img width="1117" height="698" alt="before_closeup"
src="https://github.com/user-attachments/assets/7a3b08b4-cf6f-45b7-98ba-07c473cd3b02"
/>
<img width="1117" height="698" alt="after_closeup"
src="https://github.com/user-attachments/assets/6cfc5f21-d32f-4f09-be0c-59c8c553d44f"
/>
### Architecture
The shaping integrates into the existing pipeline without changing the
public API:
1. **`Font::segment_into_runs`** — segments text into contiguous runs by
font face (grapheme-cluster aware, never splits combining sequences)
2. **`FontFace::shape_text`** — calls harfrust to shape each run,
returning glyph IDs + positioned advances/offsets
3. **`layout_shaped_run`** — emits `Glyph` structs from the shaping
output, with NOTDEF fallback to other font faces for missing glyphs
4. **Buffer recycling** — `FontsImpl` pools a `harfrust::UnicodeBuffer`
to avoid per-layout allocations
### Disclaimer
I'm far from being a good Rust programmer. Claude Code did most of the
heavy lifting here. I did my best and used my limited knowledge to avoid
making too many mistakes. If this PR isn't up to quality standards,
please don't hesitate to close it.
## Test plan
- [x] `cargo test -p epaint` — all 18 text tests pass, including 6 new
ones
- [x] `cargo clippy -p epaint --all-features` — clean
- [x] `cargo fmt` — clean
- [ ] Snapshot tests need regeneration (expected: shaping changes glyph
positions)
- New tests added:
- `test_gpos_kerning` — verifies GPOS kerning tightens "AV", "VA", "AT"
pairs
- `test_combining_diacritics` — combining tilde doesn't add extra width
- `test_shaping_basic_latin` — sanity check for Latin text
- `test_shaping_empty_string` — empty input doesn't panic
- `test_shaping_multiple_newlines` — newline splitting works correctly
- `test_shaping_mixed_font_fallback` — Latin + emoji in same string
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
- fix for https://github.com/rerun-io/reality/pull/1075
The galleys row size was calculated by looking at the last glyphs pos_x,
which got changed to be rounded to integers when we added subpixel
binning. This introduced a subtle bug which caused the width of galleys
to be slightly off.
This PR fixes this by looking at the actual cursor position instead,
which is not rounded.
Also added a test to ensure this is correct. Previously, for the second
and last line, the `x` was too close to the `0`.
<img width="48" height="67" alt="image"
src="https://github.com/user-attachments/assets/a69a4cc3-b3f3-4553-ab92-73cb2e7a358c"
/>
---------
Co-authored-by: lucasmerlin <8009393+lucasmerlin@users.noreply.github.com>
* Part of https://github.com/emilk/egui/issues/3524
This is a breaking change, as it changes the how embedded viewports
work.
Before it was up to the user to display a `egui::Window` if they wanted.
Now egui creates an `egui::Window` for you, so you only need to add the
contents.
To signal this change in behavior, `ViewportClass::Embedded` is gone and
is now called `ViewportClass::EmbeddedWindow`.
<!--
Please read the "Making a PR" section of
[`CONTRIBUTING.md`](https://github.com/emilk/egui/blob/main/CONTRIBUTING.md)
before opening a Pull Request!
* Keep your PR:s small and focused.
* The PR title is what ends up in the changelog, so make it descriptive!
* If applicable, add a screenshot or gif.
* If it is a non-trivial addition, consider adding a demo for it to
`egui_demo_lib`, or a new example.
* Do NOT open PR:s from your `master` branch, as that makes it hard for
maintainers to test and add commits to your PR.
* Remember to run `cargo fmt` and `cargo clippy`.
* Open the PR as a draft until you have self-reviewed it and run
`./scripts/check.sh`.
* When you have addressed a PR comment, mark it as resolved.
Please be patient! I will review your PR, but my time is limited!
-->
* Closes N/A
* [x] I have followed the instructions in the PR template
I'll probably come back to this and clean it up a bit. This PR
reimplements ab_glyph's functionality on top of Skrifa, a somewhat
lower-level font API that's being used in Chrome now.
Skrifa doesn't perform rasterization itself, so I'm using
[vello_cpu](https://github.com/linebender/vello) from the Linebender
project for rasterization. It's still in its early days, but I believe
it's already quite fast. It also supports color and gradient fills, so
color emoji support will be easier.
Skrifa also supports font hinting, which should make text look a bit
nicer / less blurry.
Here's the current ab_glyph rendering:
<img width="1592" height="1068" alt="image"
src="https://github.com/user-attachments/assets/2385b66e-23f8-4c6e-b8c2-ea90e0eea4e4"
/>
Here's Skrifa *without* hinting--it looks almost identical, but there
are some subpixel differences, probably due to rasterizer behavior:
<img width="1592" height="1068" alt="image"
src="https://github.com/user-attachments/assets/a815f3e9-65ac-4940-bc00-571177bef53d"
/>
Here's Skrifa *with* hinting:
<img width="1592" height="1068" alt="image"
src="https://github.com/user-attachments/assets/d6cc0669-3537-4377-bba9-ed5ef09664db"
/>
Hinting does make the horizontal strokes look a bit bolder, which makes
me wonder once again about increasing the font weight from "light" to
"regular".
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* Closes https://github.com/emilk/egui/issues/7647
This collects SnapshotResults within the Harness and adds a check to
enforce snapshot results are merged in case multiple Harnesses are
constructed within a test.
This should make snapshot updates via kitdiff/accept_snapshots.sh way
more useful since it should now always update all snapshots instead of
only the first one per test.
Sometimes when moving a window, having a tooltip attached to the mouse
pointer, or scrolling a `ScrollArea`, you would see this disturbing
effect:

This is caused by us rounding many visual elements (lines, rectangles,
text, …) to physical pixels in order to keep them sharp. If the
window/tooltip itself is not rounded to a physical pixel, then you can
get this behavior.
So from now on the position of all
areas/windows/tooltips/popups/ScrollArea gets rounded to the closes
pixel.
* Unlocked by https://github.com/emilk/egui/pull/7709
Selected text now gets the color of `visuals.selection.stroke.color`.
This means you can have inverted colors for selected text, like in the
new test:
<img width="154" height="46" alt="image"
src="https://github.com/user-attachments/assets/2666361d-d7e2-4d50-8e4d-2fcc128f1a81"
/>
It also means the color of selected text in labels matches that of the
text color of selected buttons.
This adds a new mode, `UPDATE_SNAPSHOTS=force`, which will lower the
threshold to zero, overwriting every image that is not _exactly_ the
same.
Most comparisons has a threshold because different GPUs render slightly
differently. However, setting that threshold accurately can be hard.
Sometimes a test will pass locally, but fail on CI. In those cases you
want to force an update of the failing test. You can use
`UPDATE_SNAPSHOTS=force` for that.
And sometimes a small change _should_ update all images, but the change
is so tiny that it falls under the threshold. Still, you want to make a
point of showing that these images have changes. You can use
`UPDATE_SNAPSHOTS=force` for that.