bevy/examples/3d/parenting.rs
Marek Legris 5acebed731
Transform and GlobalTransform are now Similarities (#596)
Transform and GlobalTransform are now Similarities.

This resolves precision errors and simplifies the api

Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2020-10-18 13:03:16 -07:00

65 lines
2.1 KiB
Rust

use bevy::prelude::*;
/// This example illustrates how to create parent->child relationships between entities how parent transforms
/// are propagated to their descendants
fn main() {
App::build()
.add_resource(Msaa { samples: 4 })
.add_default_plugins()
.add_startup_system(setup.system())
.add_system(rotator_system.system())
.run();
}
/// this component indicates what entities should rotate
struct Rotator;
/// rotates the parent, which will result in the child also rotating
fn rotator_system(time: Res<Time>, mut query: Query<(&Rotator, &mut Transform)>) {
for (_rotator, mut transform) in &mut query.iter() {
transform.rotation *= Quat::from_rotation_x(3.0 * time.delta_seconds);
}
}
/// 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(Mesh::from(shape::Cube { size: 1.0 }));
let cube_material_handle = materials.add(StandardMaterial {
albedo: Color::rgb(0.8, 0.7, 0.6),
..Default::default()
});
commands
// parent cube
.spawn(PbrComponents {
mesh: cube_handle,
material: cube_material_handle,
transform: Transform::from_translation(Vec3::new(0.0, 0.0, 1.0)),
..Default::default()
})
.with(Rotator)
.with_children(|parent| {
// child cube
parent.spawn(PbrComponents {
mesh: cube_handle,
material: cube_material_handle,
transform: Transform::from_translation(Vec3::new(0.0, 0.0, 3.0)),
..Default::default()
});
})
// light
.spawn(LightComponents {
transform: Transform::from_translation(Vec3::new(4.0, 5.0, -4.0)),
..Default::default()
})
// camera
.spawn(Camera3dComponents {
transform: Transform::from_translation(Vec3::new(5.0, 10.0, 10.0)).looking_at_origin(),
..Default::default()
});
}