bevy/examples/ui/ui.rs
Alice Cecile 599e5e4e76
Migrate from LegacyColor to bevy_color::Color (#12163)
# Objective

- As part of the migration process we need to a) see the end effect of
the migration on user ergonomics b) check for serious perf regressions
c) actually migrate the code
- To accomplish this, I'm going to attempt to migrate all of the
remaining user-facing usages of `LegacyColor` in one PR, being careful
to keep a clean commit history.
- Fixes #12056.

## Solution

I've chosen to use the polymorphic `Color` type as our standard
user-facing API.

- [x] Migrate `bevy_gizmos`.
- [x] Take `impl Into<Color>` in all `bevy_gizmos` APIs
- [x] Migrate sprites
- [x] Migrate UI
- [x] Migrate `ColorMaterial`
- [x] Migrate `MaterialMesh2D`
- [x] Migrate fog
- [x] Migrate lights
- [x] Migrate StandardMaterial
- [x] Migrate wireframes
- [x] Migrate clear color
- [x] Migrate text
- [x] Migrate gltf loader
- [x] Register color types for reflection
- [x] Remove `LegacyColor`
- [x] Make sure CI passes

Incidental improvements to ease migration:

- added `Color::srgba_u8`, `Color::srgba_from_array` and friends
- added `set_alpha`, `is_fully_transparent` and `is_fully_opaque` to the
`Alpha` trait
- add and immediately deprecate (lol) `Color::rgb` and friends in favor
of more explicit and consistent `Color::srgb`
- standardized on white and black for most example text colors
- added vector field traits to `LinearRgba`: ~~`Add`, `Sub`,
`AddAssign`, `SubAssign`,~~ `Mul<f32>` and `Div<f32>`. Multiplications
and divisions do not scale alpha. `Add` and `Sub` have been cut from
this PR.
- added `LinearRgba` and `Srgba` `RED/GREEN/BLUE`
- added `LinearRgba_to_f32_array` and `LinearRgba::to_u32`

## Migration Guide

Bevy's color types have changed! Wherever you used a
`bevy::render::Color`, a `bevy::color::Color` is used instead.

These are quite similar! Both are enums storing a color in a specific
color space (or to be more precise, using a specific color model).
However, each of the different color models now has its own type.

TODO...

- `Color::rgba`, `Color::rgb`, `Color::rbga_u8`, `Color::rgb_u8`,
`Color::rgb_from_array` are now `Color::srgba`, `Color::srgb`,
`Color::srgba_u8`, `Color::srgb_u8` and `Color::srgb_from_array`.
- `Color::set_a` and `Color::a` is now `Color::set_alpha` and
`Color::alpha`. These are part of the `Alpha` trait in `bevy_color`.
- `Color::is_fully_transparent` is now part of the `Alpha` trait in
`bevy_color`
- `Color::r`, `Color::set_r`, `Color::with_r` and the equivalents for
`g`, `b` `h`, `s` and `l` have been removed due to causing silent
relatively expensive conversions. Convert your `Color` into the desired
color space, perform your operations there, and then convert it back
into a polymorphic `Color` enum.
- `Color::hex` is now `Srgba::hex`. Call `.into` or construct a
`Color::Srgba` variant manually to convert it.
- `WireframeMaterial`, `ExtractedUiNode`, `ExtractedDirectionalLight`,
`ExtractedPointLight`, `ExtractedSpotLight` and `ExtractedSprite` now
store a `LinearRgba`, rather than a polymorphic `Color`
- `Color::rgb_linear` and `Color::rgba_linear` are now
`Color::linear_rgb` and `Color::linear_rgba`
- The various CSS color constants are no longer stored directly on
`Color`. Instead, they're defined in the `Srgba` color space, and
accessed via `bevy::color::palettes::css`. Call `.into()` on them to
convert them into a `Color` for quick debugging use, and consider using
the much prettier `tailwind` palette for prototyping.
- The `LIME_GREEN` color has been renamed to `LIMEGREEN` to comply with
the standard naming.
- Vector field arithmetic operations on `Color` (add, subtract, multiply
and divide by a f32) have been removed. Instead, convert your colors
into `LinearRgba` space, and perform your operations explicitly there.
This is particularly relevant when working with emissive or HDR colors,
whose color channel values are routinely outside of the ordinary 0 to 1
range.
- `Color::as_linear_rgba_f32` has been removed. Call
`LinearRgba::to_f32_array` instead, converting if needed.
- `Color::as_linear_rgba_u32` has been removed. Call
`LinearRgba::to_u32` instead, converting if needed.
- Several other color conversion methods to transform LCH or HSL colors
into float arrays or `Vec` types have been removed. Please reimplement
these externally or open a PR to re-add them if you found them
particularly useful.
- Various methods on `Color` such as `rgb` or `hsl` to convert the color
into a specific color space have been removed. Convert into
`LinearRgba`, then to the color space of your choice.
- Various implicitly-converting color value methods on `Color` such as
`r`, `g`, `b` or `h` have been removed. Please convert it into the color
space of your choice, then check these properties.
- `Color` no longer implements `AsBindGroup`. Store a `LinearRgba`
internally instead to avoid conversion costs.

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Afonso Lage <lage.afonso@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-02-29 19:35:12 +00:00

338 lines
15 KiB
Rust

//! This example illustrates the various features of Bevy UI.
use bevy::{
a11y::{
accesskit::{NodeBuilder, Role},
AccessibilityNode,
},
color::palettes::basic::GREEN,
input::mouse::{MouseScrollUnit, MouseWheel},
prelude::*,
winit::WinitSettings,
};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
// Only run the app when there is user input. This will significantly reduce CPU/GPU use.
.insert_resource(WinitSettings::desktop_app())
.add_systems(Startup, setup)
.add_systems(Update, mouse_scroll)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
// Camera
commands.spawn(Camera2dBundle::default());
// root node
commands
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
justify_content: JustifyContent::SpaceBetween,
..default()
},
..default()
})
.with_children(|parent| {
// left vertical fill (border)
parent
.spawn(NodeBundle {
style: Style {
width: Val::Px(200.),
border: UiRect::all(Val::Px(2.)),
..default()
},
background_color: Color::srgb(0.65, 0.65, 0.65).into(),
..default()
})
.with_children(|parent| {
// left vertical fill (content)
parent
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.),
..default()
},
background_color: Color::srgb(0.15, 0.15, 0.15).into(),
..default()
})
.with_children(|parent| {
// text
parent.spawn((
TextBundle::from_section(
"Text Example",
TextStyle {
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
font_size: 30.0,
..default()
},
)
.with_style(Style {
margin: UiRect::all(Val::Px(5.)),
..default()
}),
// Because this is a distinct label widget and
// not button/list item text, this is necessary
// for accessibility to treat the text accordingly.
Label,
));
});
});
// right vertical fill
parent
.spawn(NodeBundle {
style: Style {
flex_direction: FlexDirection::Column,
justify_content: JustifyContent::Center,
align_items: AlignItems::Center,
width: Val::Px(200.),
..default()
},
background_color: Color::srgb(0.15, 0.15, 0.15).into(),
..default()
})
.with_children(|parent| {
// Title
parent.spawn((
TextBundle::from_section(
"Scrolling list",
TextStyle {
font: asset_server.load("fonts/FiraSans-Bold.ttf"),
font_size: 25.,
..default()
},
),
Label,
));
// List with hidden overflow
parent
.spawn(NodeBundle {
style: Style {
flex_direction: FlexDirection::Column,
align_self: AlignSelf::Stretch,
height: Val::Percent(50.),
overflow: Overflow::clip_y(),
..default()
},
background_color: Color::srgb(0.10, 0.10, 0.10).into(),
..default()
})
.with_children(|parent| {
// Moving panel
parent
.spawn((
NodeBundle {
style: Style {
flex_direction: FlexDirection::Column,
align_items: AlignItems::Center,
..default()
},
..default()
},
ScrollingList::default(),
AccessibilityNode(NodeBuilder::new(Role::List)),
))
.with_children(|parent| {
// List items
for i in 0..30 {
parent.spawn((
TextBundle::from_section(
format!("Item {i}"),
TextStyle {
font: asset_server
.load("fonts/FiraSans-Bold.ttf"),
font_size: 20.,
..default()
},
),
Label,
AccessibilityNode(NodeBuilder::new(Role::ListItem)),
));
}
});
});
});
parent
.spawn(NodeBundle {
style: Style {
width: Val::Px(200.0),
height: Val::Px(200.0),
position_type: PositionType::Absolute,
left: Val::Px(210.),
bottom: Val::Px(10.),
border: UiRect::all(Val::Px(20.)),
..default()
},
border_color: GREEN.into(),
background_color: Color::srgb(0.4, 0.4, 1.).into(),
..default()
})
.with_children(|parent| {
parent.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
..default()
},
background_color: Color::srgb(0.8, 0.8, 1.).into(),
..default()
});
});
// render order test: reddest in the back, whitest in the front (flex center)
parent
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
position_type: PositionType::Absolute,
align_items: AlignItems::Center,
justify_content: JustifyContent::Center,
..default()
},
..default()
})
.with_children(|parent| {
parent
.spawn(NodeBundle {
style: Style {
width: Val::Px(100.0),
height: Val::Px(100.0),
..default()
},
background_color: Color::srgb(1.0, 0.0, 0.).into(),
..default()
})
.with_children(|parent| {
parent.spawn(NodeBundle {
style: Style {
// Take the size of the parent node.
width: Val::Percent(100.0),
height: Val::Percent(100.0),
position_type: PositionType::Absolute,
left: Val::Px(20.),
bottom: Val::Px(20.),
..default()
},
background_color: Color::srgb(1.0, 0.3, 0.3).into(),
..default()
});
parent.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
position_type: PositionType::Absolute,
left: Val::Px(40.),
bottom: Val::Px(40.),
..default()
},
background_color: Color::srgb(1.0, 0.5, 0.5).into(),
..default()
});
parent.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
position_type: PositionType::Absolute,
left: Val::Px(60.),
bottom: Val::Px(60.),
..default()
},
background_color: Color::srgb(1.0, 0.7, 0.7).into(),
..default()
});
// alpha test
parent.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
height: Val::Percent(100.0),
position_type: PositionType::Absolute,
left: Val::Px(80.),
bottom: Val::Px(80.),
..default()
},
background_color: Color::srgba(1.0, 0.9, 0.9, 0.4).into(),
..default()
});
});
});
// bevy logo (flex center)
parent
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.0),
position_type: PositionType::Absolute,
justify_content: JustifyContent::Center,
align_items: AlignItems::FlexStart,
..default()
},
..default()
})
.with_children(|parent| {
// bevy logo (image)
// A `NodeBundle` is used to display the logo the image as an `ImageBundle` can't automatically
// size itself with a child node present.
parent
.spawn((
NodeBundle {
style: Style {
width: Val::Px(500.0),
height: Val::Px(125.0),
margin: UiRect::top(Val::VMin(5.)),
..default()
},
// a `NodeBundle` is transparent by default, so to see the image we have to its color to `WHITE`
background_color: Color::WHITE.into(),
..default()
},
UiImage::new(asset_server.load("branding/bevy_logo_dark_big.png")),
))
.with_children(|parent| {
// alt text
// This UI node takes up no space in the layout and the `Text` component is used by the accessibility module
// and is not rendered.
parent.spawn((
NodeBundle {
style: Style {
display: Display::None,
..Default::default()
},
..Default::default()
},
Text::from_section("Bevy logo", TextStyle::default()),
));
});
});
});
}
#[derive(Component, Default)]
struct ScrollingList {
position: f32,
}
fn mouse_scroll(
mut mouse_wheel_events: EventReader<MouseWheel>,
mut query_list: Query<(&mut ScrollingList, &mut Style, &Parent, &Node)>,
query_node: Query<&Node>,
) {
for mouse_wheel_event in mouse_wheel_events.read() {
for (mut scrolling_list, mut style, parent, list_node) in &mut query_list {
let items_height = list_node.size().y;
let container_height = query_node.get(parent.get()).unwrap().size().y;
let max_scroll = (items_height - container_height).max(0.);
let dy = match mouse_wheel_event.unit {
MouseScrollUnit::Line => mouse_wheel_event.y * 20.,
MouseScrollUnit::Pixel => mouse_wheel_event.y,
};
scrolling_list.position += dy;
scrolling_list.position = scrolling_list.position.clamp(-max_scroll, 0.);
style.top = Val::Px(scrolling_list.position);
}
}
}