Function default 

pub fn default<T>() -> T
where
    T: Default,

An ergonomic abbreviation for Default::default() to make initializing structs easier.

This is especially helpful when combined with “struct update syntax”.

use bevy_utils::default;

#[derive(Default)]
struct Foo {
  a: usize,
  b: usize,
  c: usize,
}

// Normally you would initialize a struct with defaults using "struct update syntax"
// combined with `Default::default()`. This example sets `Foo::a` to 10 and the remaining
// values to their defaults.
let foo = Foo {
  a: 10,
  ..Default::default()
};

// But now you can do this, which is equivalent:
let foo = Foo {
  a: 10,
  ..default()
};

Examples found in repository

tests/3d/no_prepass.rs (line 9)

fn main() {
    App::new()
        .add_plugins(DefaultPlugins.set(PbrPlugin {
            prepass_enabled: false,
            ..default()
        }))
        .run();
}

examples/3d/spherical_area_lights.rs (line 9)

fn main() {
    App::new()
        .insert_resource(GlobalAmbientLight {
            brightness: 60.0,
            ..default()
        })
        .add_plugins(DefaultPlugins)
        .add_systems(Startup, setup)
        .run();
}

fn setup(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    // camera
    commands.spawn((
        Camera3d::default(),
        Transform::from_xyz(0.2, 1.5, 2.5).looking_at(Vec3::ZERO, Vec3::Y),
    ));

    // plane
    commands.spawn((
        Mesh3d(meshes.add(Plane3d::default().mesh().size(100.0, 100.0))),
        MeshMaterial3d(materials.add(StandardMaterial {
            base_color: Color::srgb(0.2, 0.2, 0.2),
            perceptual_roughness: 0.08,
            ..default()
        })),
    ));

    const COUNT: usize = 6;
    let position_range = -2.0..2.0;
    let radius_range = 0.0..0.4;
    let pos_len = position_range.end - position_range.start;
    let radius_len = radius_range.end - radius_range.start;
    let mesh = meshes.add(Sphere::new(1.0).mesh().uv(120, 64));

    for i in 0..COUNT {
        let percent = i as f32 / COUNT as f32;
        let radius = radius_range.start + percent * radius_len;

        // sphere light
        commands
            .spawn((
                Mesh3d(mesh.clone()),
                MeshMaterial3d(materials.add(StandardMaterial {
                    base_color: Color::srgb(0.5, 0.5, 1.0),
                    unlit: true,
                    ..default()
                })),
                Transform::from_xyz(position_range.start + percent * pos_len, 0.3, 0.0)
                    .with_scale(Vec3::splat(radius)),
            ))
            .with_child(PointLight {
                radius,
                color: Color::srgb(0.2, 0.2, 1.0),
                ..default()
            });
    }
}

examples/app/log_layers.rs (line 60)

fn main() {
    App::new()
        .add_plugins(DefaultPlugins.set(bevy::log::LogPlugin {
            custom_layer,
            fmt_layer,

            ..default()
        }))
        .add_systems(Update, log_system)
        .run();
}

examples/animation/animated_transform.rs (line 16)

fn main() {
    App::new()
        .add_plugins(DefaultPlugins)
        .insert_resource(GlobalAmbientLight {
            color: Color::WHITE,
            brightness: 150.0,
            ..default()
        })
        .add_systems(Startup, setup)
        .run();
}

fn setup(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
    mut animations: ResMut<Assets<AnimationClip>>,
    mut graphs: ResMut<Assets<AnimationGraph>>,
) {
    // Camera
    commands.spawn((
        Camera3d::default(),
        Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
    ));

    // Light
    commands.spawn((
        PointLight {
            intensity: 500_000.0,
            ..default()
        },
        Transform::from_xyz(0.0, 2.5, 0.0),
    ));

    // Let's use the `Name` component to target entities. We can use anything we
    // like, but names are convenient.
    let planet = Name::new("planet");
    let orbit_controller = Name::new("orbit_controller");
    let satellite = Name::new("satellite");

    // Creating the animation
    let mut animation = AnimationClip::default();
    // A curve can modify a single part of a transform: here, the translation.
    let planet_animation_target_id = AnimationTargetId::from_name(&planet);
    animation.add_curve_to_target(
        planet_animation_target_id,
        AnimatableCurve::new(
            animated_field!(Transform::translation),
            UnevenSampleAutoCurve::new([0.0, 1.0, 2.0, 3.0, 4.0].into_iter().zip([
                Vec3::new(1.0, 0.0, 1.0),
                Vec3::new(-1.0, 0.0, 1.0),
                Vec3::new(-1.0, 0.0, -1.0),
                Vec3::new(1.0, 0.0, -1.0),
                // in case seamless looping is wanted, the last keyframe should
                // be the same as the first one
                Vec3::new(1.0, 0.0, 1.0),
            ]))
            .expect("should be able to build translation curve because we pass in valid samples"),
        ),
    );
    // Or it can modify the rotation of the transform.
    // To find the entity to modify, the hierarchy will be traversed looking for
    // an entity with the right name at each level.
    let orbit_controller_animation_target_id =
        AnimationTargetId::from_names([planet.clone(), orbit_controller.clone()].iter());
    animation.add_curve_to_target(
        orbit_controller_animation_target_id,
        AnimatableCurve::new(
            animated_field!(Transform::rotation),
            UnevenSampleAutoCurve::new([0.0, 1.0, 2.0, 3.0, 4.0].into_iter().zip([
                Quat::IDENTITY,
                Quat::from_axis_angle(Vec3::Y, PI / 2.),
                Quat::from_axis_angle(Vec3::Y, PI / 2. * 2.),
                Quat::from_axis_angle(Vec3::Y, PI / 2. * 3.),
                Quat::IDENTITY,
            ]))
            .expect("Failed to build rotation curve"),
        ),
    );
    // If a curve in an animation is shorter than the other, it will not repeat
    // until all other curves are finished. In that case, another animation should
    // be created for each part that would have a different duration / period.
    let satellite_animation_target_id = AnimationTargetId::from_names(
        [planet.clone(), orbit_controller.clone(), satellite.clone()].iter(),
    );
    animation.add_curve_to_target(
        satellite_animation_target_id,
        AnimatableCurve::new(
            animated_field!(Transform::scale),
            UnevenSampleAutoCurve::new(
                [0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0]
                    .into_iter()
                    .zip([
                        Vec3::splat(0.8),
                        Vec3::splat(1.2),
                        Vec3::splat(0.8),
                        Vec3::splat(1.2),
                        Vec3::splat(0.8),
                        Vec3::splat(1.2),
                        Vec3::splat(0.8),
                        Vec3::splat(1.2),
                        Vec3::splat(0.8),
                    ]),
            )
            .expect("Failed to build scale curve"),
        ),
    );
    // There can be more than one curve targeting the same entity path.
    animation.add_curve_to_target(
        AnimationTargetId::from_names(
            [planet.clone(), orbit_controller.clone(), satellite.clone()].iter(),
        ),
        AnimatableCurve::new(
            animated_field!(Transform::rotation),
            UnevenSampleAutoCurve::new([0.0, 1.0, 2.0, 3.0, 4.0].into_iter().zip([
                Quat::IDENTITY,
                Quat::from_axis_angle(Vec3::Y, PI / 2.),
                Quat::from_axis_angle(Vec3::Y, PI / 2. * 2.),
                Quat::from_axis_angle(Vec3::Y, PI / 2. * 3.),
                Quat::IDENTITY,
            ]))
            .expect("should be able to build translation curve because we pass in valid samples"),
        ),
    );

    // Create the animation graph
    let (graph, animation_index) = AnimationGraph::from_clip(animations.add(animation));

    // Create the animation player, and set it to repeat
    let mut player = AnimationPlayer::default();
    player.play(animation_index).repeat();

    // Create the scene that will be animated
    // First entity is the planet
    let planet_entity = commands
        .spawn((
            Mesh3d(meshes.add(Sphere::default())),
            MeshMaterial3d(materials.add(Color::srgb(0.8, 0.7, 0.6))),
            // Add the animation graph and player
            planet,
            AnimationGraphHandle(graphs.add(graph)),
            player,
        ))
        .id();
    commands.entity(planet_entity).insert((
        planet_animation_target_id,
        AnimatedBy(planet_entity),
        children![(
            Transform::default(),
            Visibility::default(),
            orbit_controller,
            orbit_controller_animation_target_id,
            AnimatedBy(planet_entity),
            children![(
                Mesh3d(meshes.add(Cuboid::new(0.5, 0.5, 0.5))),
                MeshMaterial3d(materials.add(Color::srgb(0.3, 0.9, 0.3))),
                Transform::from_xyz(1.5, 0.0, 0.0),
                satellite_animation_target_id,
                AnimatedBy(planet_entity),
                satellite,
            )],
        )],
    ));
}

examples/gltf/gltf_skinned_mesh.rs (line 13)

fn main() {
    App::new()
        .add_plugins(DefaultPlugins)
        .insert_resource(GlobalAmbientLight {
            brightness: 750.0,
            ..default()
        })
        .add_systems(Startup, setup)
        .add_systems(Update, joint_animation)
        .run();
}

examples/app/no_renderer.rs (line 18)

fn main() {
    App::new()
        .add_plugins(
            DefaultPlugins.set(RenderPlugin {
                render_creation: WgpuSettings {
                    backends: None,
                    ..default()
                }
                .into(),
                ..default()
            }),
        )
        .run();
}

Additional examples can be found in:

• examples/app/return_after_run.rs
• examples/window/scale_factor_override.rs
• examples/app/logs.rs
• examples/2d/sprite_tile.rs
• examples/ui/window_fallthrough.rs
• examples/audio/audio_control.rs
• examples/ui/font_atlas_debug.rs
• examples/gltf/load_gltf_extras.rs
• examples/window/transparent_window.rs
• examples/3d/parenting.rs
• examples/remote/server.rs
• examples/window/screenshot.rs
• examples/3d/animated_material.rs
• examples/gltf/load_gltf.rs
• examples/gltf/update_gltf_scene.rs
• examples/dev_tools/fps_overlay.rs
• examples/ui/virtual_keyboard.rs
• examples/3d/vertex_colors.rs
• examples/2d/bloom_2d.rs
• examples/ui/ui_texture_slice.rs
• examples/ui/ui_texture_slice_flip_and_tile.rs
• examples/picking/dragdrop_picking.rs
• examples/ui/ui_texture_atlas_slice.rs
• examples/2d/mesh2d_alpha_mode.rs
• examples/2d/mesh2d_repeated_texture.rs
• examples/ui/tab_navigation.rs
• examples/ui/z_index.rs