bevy/examples/3d/parenting.rs
andristarr 7482a0d26d
aligning public apis of Time,Timer and Stopwatch (#15962)
Fixes #15834

## Migration Guide

The APIs of `Time`, `Timer` and `Stopwatch` have been cleaned up for
consistency with each other and the standard library's `Duration` type.
The following methods have been renamed:

- `Stowatch::paused` -> `Stopwatch::is_paused`
- `Time::elapsed_seconds` -> `Time::elasped_secs` (including `_f64` and
`_wrapped` variants)
2024-10-16 21:09:32 +00:00

60 lines
1.8 KiB
Rust

//! Illustrates how to create parent-child relationships between entities and how parent transforms
//! are propagated to their descendants.
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, rotator_system)
.run();
}
/// this component indicates what entities should rotate
#[derive(Component)]
struct Rotator;
/// rotates the parent, which will result in the child also rotating
fn rotator_system(time: Res<Time>, mut query: Query<&mut Transform, With<Rotator>>) {
for mut transform in &mut query {
transform.rotate_x(3.0 * time.delta_secs());
}
}
/// set up a simple scene with a "parent" cube and a "child" cube
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
let cube_handle = meshes.add(Cuboid::new(2.0, 2.0, 2.0));
let cube_material_handle = materials.add(StandardMaterial {
base_color: Color::srgb(0.8, 0.7, 0.6),
..default()
});
// parent cube
commands
.spawn((
Mesh3d(cube_handle.clone()),
MeshMaterial3d(cube_material_handle.clone()),
Transform::from_xyz(0.0, 0.0, 1.0),
Rotator,
))
.with_children(|parent| {
// child cube
parent.spawn((
Mesh3d(cube_handle),
MeshMaterial3d(cube_material_handle),
Transform::from_xyz(0.0, 0.0, 3.0),
));
});
// light
commands.spawn((PointLight::default(), Transform::from_xyz(4.0, 5.0, -4.0)));
// camera
commands.spawn((
Camera3d::default(),
Transform::from_xyz(5.0, 10.0, 10.0).looking_at(Vec3::ZERO, Vec3::Y),
));
}