mirror of
https://github.com/bevyengine/bevy
synced 2024-11-30 00:20:20 +00:00
1ba7429371
# Objective Provide a starting point for #3951, or a partial solution. Providing a few comment blocks to discuss, and hopefully find better one in the process. ## Solution Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less. ## Changelog - Moved some existing comments from main() functions in the 2d examples to the file header level - Wrote some more comment blocks for most other 2d examples TODO: - [x] 2d/sprite_sheet, wasnt able to come up with something good yet - [x] all other example groups... Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed. I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please.
59 lines
1.9 KiB
Rust
59 lines
1.9 KiB
Rust
//! Illustrates how to (constantly) rotate an object around an axis.
|
|
|
|
use bevy::prelude::*;
|
|
|
|
use std::f32::consts::PI;
|
|
|
|
const FULL_TURN: f32 = 2.0 * PI;
|
|
|
|
// 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_startup_system(setup)
|
|
.add_system(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_bundle(PbrBundle {
|
|
mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
|
|
material: materials.add(Color::WHITE.into()),
|
|
transform: Transform::from_translation(Vec3::ZERO),
|
|
..Default::default()
|
|
})
|
|
.insert(Rotatable { speed: 0.3 });
|
|
|
|
// Spawn a camera looking at the entities to show what's happening in this example.
|
|
commands.spawn_bundle(PerspectiveCameraBundle {
|
|
transform: Transform::from_xyz(0.0, 10.0, 20.0).looking_at(Vec3::ZERO, Vec3::Y),
|
|
..Default::default()
|
|
});
|
|
|
|
// Add a light source for better 3d visibility.
|
|
commands.spawn_bundle(PointLightBundle {
|
|
transform: Transform::from_translation(Vec3::ONE * 3.0),
|
|
..Default::default()
|
|
});
|
|
}
|
|
|
|
// This system will rotate any entity in the scene with an assigned Rotatable around its z-axis.
|
|
fn rotate_cube(mut cubes: Query<(&mut Transform, &Rotatable)>, timer: Res<Time>) {
|
|
for (mut transform, cube) in cubes.iter_mut() {
|
|
// The speed is taken as a percentage of a full 360 degree turn.
|
|
// The timers delta_seconds is used to smooth out the movement.
|
|
let rotation_change = Quat::from_rotation_y(FULL_TURN * cube.speed * timer.delta_seconds());
|
|
transform.rotate(rotation_change);
|
|
}
|
|
}
|