Flat Commands

Extension traits for bevy for spawning entity hierarchies without nesting or storing ids.

Examples

Before

rust fn setup(mut commands: Commands) { commands .spawn_bundle(PbrBundle { transform: Transform::from_xyz(1.0, 1.0, 1.0), ..Default::default() }) .with_children(|parent| { parent .spawn_bundle(PbrBundle { transform: Transform::from_xyz(1.0, 1.0, 1.0), ..Default::default() }) .spawn_bundle(PbrBundle { transform: Transform::from_xyz(2.0, 2.0, 2.0), ..Default::default() }) }); }

or

rust fn setup(mut commands: Commands) { let child_1 = commands .spawn_bundle(PbrBundle { transform: Transform::from_xyz(1.0, 1.0, 1.0), ..Default::default() }) .id(); let child_2 = commands .spawn_bundle(PbrBundle { transform: Transform::from_xyz(2.0, 2.0, 2.0), ..Default::default() }) .id(); commands .spawn_bundle(PbrBundle { transform: Transform::from_xyz(1.0, 1.0, 1.0), ..Default::default() }) .push_child(child_1) .push_child(child_1); }

after

```rust use flat_commands::*;

fn setup(mut commands: Commands) { commands .spawnroot(PbrBundle { transform: Transform::fromxyz(1.0, 1.0, 1.0), ..Default::default() }) .withchild(PbrBundle { transform: Transform::fromxyz(1.0, 1.0, 1.0), ..Default::default() }) .withsibling(PbrBundle { transform: Transform::fromxyz(2.0, 2.0, 2.0), ..Default::default() }); } ``` #

Before

```rust pub fn spawntextbox( mut commands: Commands, asset_server: Res, ) {

commands.spawn_bundle(NodeBundle {
    style: Style {
        position_type: PositionType::Absolute,
        position: Rect { left: Val::Px(100.0), bottom: Val::Px(100.0), ..Default::default() },
        padding: Rect::all(Val::Px(2.0)),
        ..Default::default()
    },
    ..Default::default()
})
.with_children(|builder| {
    builder.spawn_bundle(NodeBundle {
            color: UiColor (Color::DARK_GRAY),
            style: Style {
                padding: Rect::all(Val::Px(4.0)),
                ..Default::default()
            },
            ..Default::default()
        }
    )
    .with_children(|builder| {
        builder.spawn_bundle(TextBundle {
            text: Text::with_section(
                "Hello, world!",
                TextStyle {
                    font: asset_server.load("FiraMono-Regular.ttf"),
                    font_size: 16.0,
                    color: Color::ANTIQUE_WHITE,
                },
                TextAlignment::default()
            ),
             ..Default::default()
        });
    });
});

} ```

after

```rust use flat_commands::*;

pub fn spawntextbox( mut commands: Commands, assetserver: Res, ) { commands.spawnroot(NodeBundle { style: Style { positiontype: PositionType::Absolute, position: Rect { left: Val::Px(100.0), bottom: Val::Px(100.0), ..Default::default() }, padding: Rect::all(Val::Px(2.0)), ..Default::default() }, ..Default::default() }) .withchild(NodeBundle { color: UiColor (Color::DARKGRAY), style: Style { padding: Rect::all(Val::Px(4.0)), ..Default::default() }, ..Default::default() }) .withchild(TextBundle { text: Text::withsection( "Hello, world!", TextStyle { font: assetserver.load("FiraMono-Regular.ttf"), fontsize: 16.0, color: Color::ANTIQUEWHITE, }, TextAlignment::default() ), ..Default::default() }); } ``` #

Before

```rust fn spawnbranchinghierachy( commands: &mut Commands ) -> Entity { let id = commands.spawn().id();

commands.entity(id)
.with_children(|builder| {
    builder
    .spawn()
    .with_children(|builder| {
        builder
        .spawn()
        .with_children(|builder| {
            builder
            .spawn();

            builder
            .spawn();
        });
    });

    builder
    .spawn()
    .with_children(|builder| {
        builder
        .spawn()
        .with_children(|builder| {
            builder
            .spawn();

            builder
            .spawn();
        });
    });

    builder
    .spawn()
    .with_children(|builder| {
        builder
        .spawn()
        .with_children(|builder| {
            builder
            .spawn();

            builder
            .spawn();
        });
    });
});

id

} ```

after

```rust use flat_commands::*;

fn spawnbranchinghierachy( commands: &mut Commands ) -> Entity { commands .spawnemptyroot() .withdescendants(|localroot| { localroot .withemptychild() .withemptychild() .withemptysibling() }) .withdescendants(|localroot| { localroot .withemptychild() .withemptychild() .withemptysibling() }) .withdescendants(|localroot| { localroot .withemptychild() .withemptychild() .withemptysibling() }) .rootid() } ```

or

```rust use flat_commands::*;

fn spawnhierachy( mut commands: Commands ) -> Entity { let root = commands .spawnempty_root();

root
.with_empty_child()
.with_empty_child()
.with_empty_sibling();

root
.with_empty_child()
.with_empty_child()
.with_empty_sibling();

root
.with_empty_child()
.with_empty_child()
.with_empty_sibling()
.root_id()

} ``` #

EntityCommands also implements ParentCommands

```rust use flat_commands::*;

fn spawnhierachy( mut commands: Commands ) { let entitycommands = commands.spawn(); entitycommands .insert(MyComponent) .withemptychild() .withempty_sibling(); }

``` #

Batched child spawning

```rust use flat_commands::*;

fn spawnbrood( mut commands: Commands, assetserver: Res, ) { let font = assetserver.load("fonts/FiraSans-Bold.ttf"); commands.spawnroot(NodeBundle { ..Default::default() }) .withchildbatch((0..30).map(move |i| { TextBundle { style: Style { flexshrink: 0., size: Size::new(Val::Undefined, Val::Px(20.)), margin: Rect { left: Val::Auto, right: Val::Auto, ..Default::default() }, ..Default::default() }, text: Text::withsection( format!("Item {}", i), TextStyle { font: font.clone(), font_size: 20., color: Color::RED, }, Default::default(), ), ..Default::default() } ); } ``` #

Other Info