bevy/examples/transforms/translation.rs
Alice Cecile de004da8d5
Rename bevy_render::Color to LegacyColor (#12069)
# Objective

The migration process for `bevy_color` (#12013) will be fairly involved:
there will be hundreds of affected files, and a large number of APIs.

## Solution

To allow us to proceed granularly, we're going to keep both
`bevy_color::Color` (new) and `bevy_render::Color` (old) around until
the migration is complete.

However, simply doing this directly is confusing! They're both called
`Color`, making it very hard to tell when a portion of the code has been
ported.

As discussed in #12056, by renaming the old `Color` type, we can make it
easier to gradually migrate over, one API at a time.

## Migration Guide

THIS MIGRATION GUIDE INTENTIONALLY LEFT BLANK.

This change should not be shipped to end users: delete this section in
the final migration guide!

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
2024-02-24 21:35:32 +00:00

75 lines
2.2 KiB
Rust

//! Illustrates how to move an object along an axis.
use bevy::prelude::*;
// Define a struct to keep some information about our entity.
// Here it's an arbitrary movement speed, the spawn location, and a maximum distance from it.
#[derive(Component)]
struct Movable {
spawn: Vec3,
max_distance: f32,
speed: f32,
}
// Implement a utility function for easier Movable struct creation.
impl Movable {
fn new(spawn: Vec3) -> Self {
Movable {
spawn,
max_distance: 5.0,
speed: 2.0,
}
}
}
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, move_cube)
.run();
}
// Startup system to setup the scene and spawn all relevant entities.
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
// Add a cube to visualize translation.
let entity_spawn = Vec3::ZERO;
commands.spawn((
PbrBundle {
mesh: meshes.add(Cuboid::default()),
material: materials.add(LegacyColor::WHITE),
transform: Transform::from_translation(entity_spawn),
..default()
},
Movable::new(entity_spawn),
));
// Spawn a camera looking at the entities to show what's happening in this example.
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(0.0, 10.0, 20.0).looking_at(entity_spawn, Vec3::Y),
..default()
});
// Add a light source for better 3d visibility.
commands.spawn(DirectionalLightBundle {
transform: Transform::from_xyz(3.0, 3.0, 3.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
});
}
// This system will move all Movable entities with a Transform
fn move_cube(mut cubes: Query<(&mut Transform, &mut Movable)>, timer: Res<Time>) {
for (mut transform, mut cube) in &mut cubes {
// Check if the entity moved too far from its spawn, if so invert the moving direction.
if (cube.spawn - transform.translation).length() > cube.max_distance {
cube.speed *= -1.0;
}
let direction = transform.local_x();
transform.translation += direction * cube.speed * timer.delta_seconds();
}
}