bevy/examples/transforms/3d_rotation.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

58 lines
1.8 KiB
Rust

//! Illustrates how to rotate an object around an axis.
use bevy::prelude::*;
use std::f32::consts::TAU;
// Define a component to designate a rotation speed to an entity.
#[derive(Component)]
struct Rotatable {
speed: f32,
}
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, rotate_cube)
.run();
}
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
// Spawn a cube to rotate.
commands.spawn((
PbrBundle {
mesh: meshes.add(Cuboid::default()),
material: materials.add(LegacyColor::WHITE),
transform: Transform::from_translation(Vec3::ZERO),
..default()
},
Rotatable { speed: 0.3 },
));
// 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(Vec3::ZERO, Vec3::Y),
..default()
});
// Add a light source so we can see clearly.
commands.spawn(DirectionalLightBundle {
transform: Transform::from_xyz(3.0, 3.0, 3.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
});
}
// This system will rotate any entity in the scene with a Rotatable component around its y-axis.
fn rotate_cube(mut cubes: Query<(&mut Transform, &Rotatable)>, timer: Res<Time>) {
for (mut transform, cube) in &mut cubes {
// The speed is first multiplied by TAU which is a full rotation (360deg) in radians,
// and then multiplied by delta_seconds which is the time that passed last frame.
// In other words. Speed is equal to the amount of rotations per second.
transform.rotate_y(cube.speed * TAU * timer.delta_seconds());
}
}