This adds a generic way of telling containers to close from their child
`Ui`s.
* Part of #5727
* [x] I have followed the instructions in the PR template
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
I got annoyed by all the slightly different variations of "collect
snapshot results and unwrap them at the end of test" I've written, so I
added a struct to make this nice and simple.
One controversial thing: It panics when dropped. I wanted to ensure
people cannot forget to unwrap the results at the end, and this was the
best thing I could come up with. I don't think this is possible via
clippy lint or something like that.
* [x] I have followed the instructions in the PR template
Breaking change!
* `Rounding` -> `CornerRadius`
* `rounding` -> `corner_radius`
This is to:
* Clarify
* Conform to other systems (e.g. Figma)
* Avoid confusion with `GuiRounding`
## Defining what `Rounding` is
This PR defines what `Rounding` means: it is the corner radius of
underlying `RectShape` rectangle. If you use `StrokeKind::Inside`, this
means the rounding is of the outer part of the stroke. Conversely, if
you use `StrokeKind::Outside`, the stroke is outside the rounded
rectangle, so the stroke has an inner radius or `rounding`, and an outer
radius that is larger by `stroke.width`.
This definitions is the same as Figma uses.
## Improving general shape rendering
The rendering of filled shapes (rectangles, circles, paths, bezier) has
been rewritten. Instead of first painting the fill with the stroke on
top, we now paint them as one single mesh with shared vertices at the
border. This has several benefits:
* Less work (faster and with fewer vertices produced)
* No overdraw (nicer rendering of translucent shapes)
* Correct blending of stroke and fill
The logic for rendering thin strokes has also been improved, so that the
width of a stroke of `StrokeKind::Outside` never affects the filled area
(this used to be wrong for thin strokes).
## Improving of rectangle rendering
Rectangles also has specific improvements in how thin rectangles are
painted.
The handling of "Blur width" is also a lot better, and now works for
rectangles with strokes.
There also used to be bugs with specific combinations of corner radius
and stroke width, that are now fixed.
## But why?
With the new `egui::Scene` we end up with a lot of zoomed out shapes,
with sub-pixel strokes. These need to look good! One thing led to
another, and then I became obsessive 😅
## Tessellation Test
In order to investigate the rendering, I created a Tessellation Test in
the `egui_demo_lib`.
[Try it
here](https://egui-pr-preview.github.io/pr/5669-emilkimprove-tessellator)


This is a breaking change, requiring users to think about wether the
stroke is inside/centered/outside the rect.
When in doubt, add `egui::StrokeKind::Inside` to the function call.
Previously, `Harness::run` just called `Harness::step` 3 times. If that
wasn't enough, tests would often call run multiple times so all
animations would finish properly.
Also, I introduced `HarnessBuilder::with_step_dt` to customize with how
big of a dt each frame is called. I set the default to 1.0 / 6.0 (~6fps)
so we don't waste cpu in tests waiting on animations.
`HarnessBuilder::max_steps` allows us to control how many steps
`Harness::run` should run before panicing.
The default is 6, so we run for up to 1.0 logical seconds (six frames at
6 fps), which should be enough to finish most animations.
Turns out a lot of snapshots where rendered before fully shown and had a
light opacity, those are now fixed.
* [x] I have followed the instructions in the PR template
* Part of https://github.com/emilk/egui/issues/4019
`Frame` now includes the width of the stroke as part of its size. From
the new docs:
### `Frame` docs
The total (outer) size of a frame is `content_size + inner_margin +
2*stroke.width + outer_margin`.
Everything within the stroke is filled with the fill color (if any).
```text
+-----------------^-------------------------------------- -+
| | outer_margin |
| +------------v----^------------------------------+ |
| | | stroke width | |
| | +------------v---^---------------------+ | |
| | | | inner_margin | | |
| | | +-----------v----------------+ | | |
| | | | ^ | | | |
| | | | | | | | |
| | | |<------ content_size ------>| | | |
| | | | | | | | |
| | | | v | | | |
| | | +------- content_rect -------+ | | |
| | | | | |
| | +-------------fill_rect ---------------+ | |
| | | |
| +----------------- widget_rect ------------------+ |
| |
+---------------------- outer_rect ------------------------+
```
The four rectangles, from inside to outside, are:
* `content_rect`: the rectangle that is made available to the inner
[`Ui`] or widget.
* `fill_rect`: the rectangle that is filled with the fill color (inside
the stroke, if any).
* `widget_rect`: is the interactive part of the widget (what sense
clicks etc).
* `outer_rect`: what is allocated in the outer [`Ui`], and is what is
returned by [`Response::rect`].
### Notes
This required rewriting a lot of the layout code for `egui::Window`,
which was a massive pain. But now the window margin and stroke width is
properly accounted for everywhere.
This adds `WidgetType::Image` and correctly sets it in the Image widget.
This allows us to query for images in kittest tests and tells accesskit
that a node is an image.
It also adds `Image::alt_text` to set a text that will be shown if the
image fails to load and will be read via screen readers. This also
allows us to query images by label in kittest.
* [x] I have followed the instructions in the PR template
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Hey! I am not sure if this is something that's been considered before
and decided against (I couldn't find any PR's or issues).
This change removes the internal profiling macros in library crates and
the `puffin` feature and replaces it with similar functions in the
[profiling](https://github.com/aclysma/profiling) crate. This crate
provides a layer of abstraction over various profiler instrumentation
crates and allows library users to pick their favorite (supported)
profiler.
An additional benefit for puffin users is that dependencies of egui are
included in the instrumentation output too (mainly wgpu which uses the
profiling crate), so more details might be available when profiling.
A breaking change is that instead of using the `puffin` feature on egui,
users that want to profile the crate with puffin instead have to enable
the `profile-with-puffin` feature on the profiling crate. Similarly they
could instead choose to use `profile-with-tracy` etc.
I tried to add a 'tracy' feature to egui_demo_app in order to showcase ,
however the /scripts/check.sh currently breaks on mutually exclusive
features (which this introduces), so I decided against including it for
the initial PR. I'm happy to iterate more on this if there is interest
in taking this PR though.
Screenshot showing the additional info for wgpu now available when using
puffin

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A very common usability issue on egui-wgpu callbacks is that `paint`
can't access any data that doesn't strictly outlive the callback
resources' data. E.g. if the callback resources have an `Arc` to some
resource manager, you can't easily pull out resources since you
statically needed to ensure that those resource references outlived the
renderpass, whose lifetime was only constrained to the callback
resources themselves.
Wgpu 22 no longer has this restriction! Its (render/compute-)passes take
care of the lifetime of any passed resource internally. The lifetime
constraint is _still_ opt-out since it protects from a common runtime
error of adding commands/passes on the parent encoder while a previously
created pass wasn't closed yet.
This is not a concern in egui-wgpu since the paint method where we have
to access the render pass doesn't even have access to the encoder!
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- I fixed the TODO to use the `log` crate instead of `eprintln`
- Set the rust-version in the `scripts/check.sh` to the same as egui is
on
- I made xtask use anyhow to remove some unwraps
* [x] I have followed the instructions in the PR template
* Closes https://github.com/emilk/egui/issues/4976
* Part of #4378
* Implements parts of #843
### Background
Some widgets (like `Grid` and `Table`) needs to know the width of future
elements in order to properly size themselves. For instance, the width
of the first column of a grid may not be known until all rows of the
grid has been added, at which point it is too late. Therefore these
widgets store sizes from the previous frame. This leads to "first-frame
jitter", were the content is placed in the wrong place for one frame,
before being accurately laid out in subsequent frames.
### What
This PR adds the function `ctx.request_discard` which discards the
visual output and does another _pass_, i.e. calls the whole app UI code
once again (in eframe this means calling `App::update` again). This will
thus discard the shapes produced by the wrongly placed widgets, and
replace it with new shapes. Note that only the visual output is
discarded - all other output events are accumulated.
Calling `ctx.request_discard` should only be done in very rare
circumstances, e.g. when a `Grid` is first shown. Calling it every frame
will mean the UI code will become unnecessarily slow.
Two safe-guards are in place:
* `Options::max_passes` is by default 2, meaning egui will never do more
than 2 passes even if `request_discard` is called on every pass
* If multiple passes is done for multiple frames in a row, a warning
will be printed on the screen in debug builds:

### Breaking changes
A bunch of things that had "frame" in the name now has "pass" in them
instead:
* Functions called `begin_frame` and `end_frame` are now called
`begin_pass` and `end_pass`
* `FrameState` is now `PassState`
* etc
### TODO
* [x] Figure out good names for everything (`ctx.request_discard`)
* [x] Add API to query if we're gonna repeat this frame (to early-out
from expensive rendering)
* [x] Clear up naming confusion (pass vs frame) e.g. for `FrameState`
* [x] Figure out when to call this
* [x] Show warning on screen when there are several frames in a row with
multiple passes
* [x] Document
* [x] Default on or off?
* [x] Change `Context::frame_nr` name/docs
* [x] Rename `Context::begin_frame/end_frame` and deprecate the old ones
* [x] Test with Rerun
* [x] Document breaking changes
* Closes <https://github.com/emilk/egui/issues/4490>
* [x] I have followed the instructions in the PR template
---
Unfortunately, this PR contains a bunch of breaking changes because
`Context` no longer has one style, but two. I could try to add some of
the methods back if that's desired.
The most subtle change is probably that `style_mut` mutates both the
dark and the light style (which from the usage in egui itself felt like
the right choice but might be surprising to users).
I decided to deviate a bit from the data structure suggested in the
linked issue.
Instead of this:
```rust
pub theme: Theme, // Dark or Light
pub follow_system_theme: bool, // Change [`Self::theme`] based on `RawInput::system_theme`?
```
I decided to add a `ThemePreference` enum and track the current system
theme separately.
This has a couple of benefits:
* The user's theme choice is not magically overwritten on the next
frame.
* A widget for changing the theme preference only needs to know the
`ThemePreference` and not two values.
* Persisting the `theme_preference` is fine (as opposed to persisting
the `theme` field which may actually be the system theme).
The `small_toggle_button` currently only toggles between dark and light
(so you can never get back to following the system). I think it's easy
to improve on this in a follow-up PR :)
I made the function `pub(crate)` for now because it should eventually be
a method on `ThemePreference`, not `Theme`.
To showcase the new capabilities I added a new example that uses
different "accent" colors in dark and light mode:
<img
src="https://github.com/user-attachments/assets/0bf728c6-2720-47b0-a908-18bd250d15a6"
width="250" alt="A screenshot of egui's widget gallery demo in dark mode
using a purple accent color instead of the default blue accent">
<img
src="https://github.com/user-attachments/assets/e816b380-3e59-4f11-b841-8c20285988d6"
width="250" alt="A screenshot of egui's widget gallery demo in light
mode using a green accent color instead of the default blue accent">
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
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* Closes https://github.com/emilk/egui/issues/3549
* [X] I have followed the instructions in the PR template
The syntax highlighting font size was always hardcoded to 12 or 10
depending on what case it was hitting (so not consistent). This is
particularly noticeable when you increase the font size to something
larger for the rest of the ui.
With this the default monospace font size is used by default.
Since the issue is closely related to #3549 I decided to implement the
ability to use override_font_id too.
## Visualized
Default monospace is set to 15 in all the pictures
Before/After without syntect:

Before/after _with_ syntect:

Font override after without/with syntect (monospace = 20):

### Breaking changes
- `CodeTheme::dark` and `CodeTheme::light` takes in the font size
- `CodeTheme::from_memory` takes in `Style`
- `highlight` function takes in `Style`
You can see this feature in action
[here](https://docs.rs/sysinfo/latest/src/sysinfo/common/system.rs.html#46)
or on any of dtolnay's crates and many others. I found myself going
through your project code recently on docs.rs and I was a bit sad I
couldn't have this feature enabled. This should fix it at next release.
:)
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* Closes <https://github.com/emilk/egui/issues/4776>
* [x] I have followed the instructions in the PR template
I've been meaning to look into this for a while but finally bit the
bullet this week. Contrary to what I initially thought, the problem of
blurry lines is unrelated to feathering because it also happens with
feathering disabled.
The root cause is that lines tend to land on pixel boundaries, and
because of that, frequently used strokes (e.g. 1pt), end up partially
covering pixels. This is especially noticeable on 1ppp displays.
There were a couple of things to fix, namely: individual lines like
separators and indents but also shape strokes (e.g. Frame).
Lines were easy, I just made sure we round them to the nearest pixel
_center_, instead of the nearest pixel boundary.
Strokes were a little more complicated. To illustrate why, here’s an
example: if we're rendering a 5x5 rect (black fill, red stroke), we
would expect to see something like this:

The fill and the stroke to cover entire pixels. Instead, egui was
painting the stroke partially inside and partially outside, centered
around the shape’s path (blue line):

Both methods are valid for different use-cases but the first one is what
we’d typically want for UIs to feel crisp and pixel perfect. It's also
how CSS borders work (related to #4019 and #3284).
Luckily, we can use the normal computed for each `PathPoint` to adjust
the location of the stroke to be outside, inside, or in the middle.
These also are the 3 types of strokes available in tools like Photoshop.
This PR introduces an enum `StrokeKind` which determines if a
`PathStroke` should be tessellated outside, inside, or _on_ the path
itself. Where "outside" is defined by the directions normals point to.
Tessellator will now use `StrokeKind::Outside` for closed shapes like
rect, ellipse, etc. And `StrokeKind::Middle` for the rest since there's
no meaningful "outside" concept for open paths. This PR doesn't expose
`StrokeKind` to user-land, but we can implement that later so that users
can render shapes and decide where to place the stroke.
### Strokes test
(blue lines represent the size of the rect being rendered)
`Stroke::Middle` (current behavior, 1px and 3px are blurry)

`Stroke::Outside` (proposed default behavior for closed paths)

`Stroke::Inside` (for completeness but unused at the moment)

### Demo App
The best way to review this PR is to run the demo on a 1ppp display,
especially to test hover effects. Everything should look crisper. Also
run it in a higher dpi screen to test that nothing broke 🙏.
Before:

After (notice the sharper lines):

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I removed (I hope so) all wildcard imports I found.
For me on my pc this improved the build time:
- for egui -5s
- for eframe -12s
* [x] I have followed the instructions in the PR template
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All the other crates in egui have serde as an optional dependency -
which is great! But sadly egui_extras unconditionally includes it, which
adds a bunch of code to stuff that may not care for it. This PR gates
serde support behind a new `serde` feature.
This is a breaking change; if that's undesirable then we can add it as a
default feature instead, though that wouldn't match any of the other
crates.
The closure passed to `eframe::run_native` now returns a `Result`,
allowing you to return an error during app creation, which will be
returned to the caller of `run_native`.
This means you need to wrap your `Box::new(MyApp::new(…))` in an
`Ok(…)`.
* Closes https://github.com/emilk/egui/issues/4474
0.20 has a bunch of bugs that will be fixed by:
* https://github.com/gfx-rs/wgpu/pull/5681
At Rerun, we don't want to wait for the wgpu 0.20.1 patch release before
we update egui, so we will temporarily downgrade to wgpu 0.19
After reverting I'll open a new PR that will update to 0.20 again, with
the intention of merging that once 0.20.1 is released.
* Closes#4473
This PR introduce `Style::wrap_mode`, which adds support for text
truncation in addition to text wrapping. This PR also update some width
calculation of the ComboBox.
#### Core
- Add `egui::TextWrapMode` (pure enum with `Extend`, `Wrap`, `Truncate`)
- Add `Style::wrap_mode: Option<tTextWrapMode>`
- **DEPRECATED**: `Style::wrap`, use `Style::wrap_mode` instead.
- Add `Ui::wrap_mode()` to return the wrap mode to use in the current
ui. If specified in `Style`, return it. Otherwise, return
`TextWrapMode::Wrap` for vertical layout and wrapping horizontal layout,
and `TextWrapMode::Extend` otherwise.
- **DEPRECATED**: `Ui::wrap_text()`, use `Ui::wrap_mode` instead.
#### Widget
- Update the width calculation of the `ComboBox` button (_not_ its popup
menu).
- Now, `ComboBox::width()` (defaulting to `Spacing::combo_width`) is
always considered a minimum width and will extend the `Ui`, regardless
of the selected text width and wrap mode.
- Introduce `ComboBox::wrap_mode`, which overrides `Ui::wrap_mode` for
the selected text layout.
- Note: since `ComboBox` uses `ui.horizontal` internally, the default
wrap mode is always `TextWrapMode::Extend`, regardless of the caller's
`Ui`'s layout.
- The `ComboBox` button no longer extend to `ui.available_width()` with
wrapping is enabled.
- **BREAKING**: `ComboBox::wrap()` no longer has a `bool` argument and
is now a short-hand for `ComboBox::wrap_mode(TextWrapMode::Wrap)`.
- Added `ComboBox::truncate()` as short-hand for
`ComboBox::wrap_mode(TextWrapMode::Truncate)`.
- Update `Label`
- Add `Label::wrap_mode()` to specify the text wrap mode.
- **BREAKING**: `Label::wrap()` no longer has a `bool` argument and is
now a short-hand for `Label::wrap_mode(TextWrapMode::Wrap)`.
- **BREAKING**: `Label::truncate()` no longer has a `bool` argument and
is now a short-hand for `Label::wrap_mode(TextWrapMode::Truncate)`.
- Update `Button`
- Add `Button::wrap_mode()` to specify the text wrap mode.
- **BREAKING**: `Button::wrap()` no longer has a `bool` argument and is
now a short-hand for `Button::wrap_mode(TextWrapMode::Wrap)`.
- Added `Button::truncate()` as short-hand for
`Button::wrap_mode(TextWrapMode::Truncate)`.
#### Low-level
- **BREAKING**: `WidgetText::into_galley()` now takes an
`Option<TextWrapMode>` instead of a `Option<bool>` argument.
- **BREAKING**: `WidgetText::into_galley_impl(()` now takes a
`TextWrapping` argument instead of `wrap: bool` and `availalbe_width:
f32` arguments.
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
## Summary
This PR introduces a new configuration option `reduce_texture_memory` in
`egui`.
## Changes
- Added `reduce_texture_memory` option in `egui`. When set to `true`,
`egui` will discard the loaded image data after the texture is uploaded
to the GPU, reducing memory usage. This is beneficial when handling a
large number of images and retaining the image data is unnecessary,
potentially saving substantial memory. However, this makes it impossible
to serialize the loaded images or render on non-GPU systems. Default is
`false`.
## Impact
This new configuration option gives users more control over their memory
usage, especially when dealing with a large number or large resolution
of images. It allows users to optimize their applications based on their
specific needs and constraints.
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Inspired by:
44d65f41ac/Cargo.toml (L65)
I took the liberty of removing that comment since I *think* that I got
all "relevant" ones (showing up more than once, sort of).
Removes `egui_assert` etc and replaces it with normal `debug_assert`
calls.
Previously you could opt-in to more runtime checks using feature flags.
Now these extra runtime checks are always enabled for debug builds.
You are most likely to encounter them if you use negative sizes or NaNs
or other similar bugs.
These usually indicate bugs in user space.
updates the wgpu version to 0.20 and changes the API calls accordingly.
I had to update wasm-bindgen to "0.2.92". Otherwise, I got this error
for the demo app:
```
error: failed to select a version for `wasm-bindgen`.
... required by package `js-sys v0.3.69`
... which satisfies dependency `js-sys = "^0.3.69"` of package `eframe v0.27.2 (/home/user/Projects/egui/crates/eframe)`
... which satisfies path dependency `eframe` (locked to 0.27.2) of package `confirm_exit v0.1.0 (/home/user/Projects/egui/examples/confirm_exit)`
versions that meet the requirements `^0.2.92` are: 0.2.92
all possible versions conflict with previously selected packages.
previously selected package `wasm-bindgen v0.2.90`
... which satisfies dependency `wasm-bindgen = "=0.2.90"` of package `egui_demo_app v0.27.2 (/home/user/Projects/egui/crates/egui_demo_app)`
failed to select a version for `wasm-bindgen` which could resolve this conflict
```
Why is it locked to this version right now?
I ran the tests, checked the web demo and my own projects, and
everything seems to work fine with wgpu 0.20.
---------
Co-authored-by: Andreas Reich <r_andreas2@web.de>
An alternative to the "Phone Size" button useful for testing
`ViewportCommand::InnerSize`.
I created this to make it easy to debug
https://github.com/emilk/egui/issues/4196 there are more details there.