bevy/examples/stress_tests/many_sprites.rs
Mark Schmale 1ba7429371 Doc/module style doc blocks for examples (#4438)
# 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.
2022-05-16 13:53:20 +00:00

98 lines
3.1 KiB
Rust

//! Renders a lot of sprites to allow performance testing.
//! See <https://github.com/bevyengine/bevy/pull/1492>
//!
//! It sets up many sprites in different sizes and rotations, and at different scales in the world,
//! and moves the camera over them to see how well frustum culling works.
use bevy::{
diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
math::Quat,
prelude::*,
render::camera::Camera,
};
use rand::Rng;
const CAMERA_SPEED: f32 = 1000.0;
fn main() {
App::new()
// Since this is also used as a benchmark, we want it to display performance data.
.add_plugin(LogDiagnosticsPlugin::default())
.add_plugin(FrameTimeDiagnosticsPlugin::default())
.add_plugins(DefaultPlugins)
.add_startup_system(setup)
.add_system(print_sprite_count)
.add_system(move_camera.after(print_sprite_count))
.run();
}
fn setup(mut commands: Commands, assets: Res<AssetServer>) {
let mut rng = rand::thread_rng();
let tile_size = Vec2::splat(64.0);
let map_size = Vec2::splat(320.0);
let half_x = (map_size.x / 2.0) as i32;
let half_y = (map_size.y / 2.0) as i32;
let sprite_handle = assets.load("branding/icon.png");
// Spawns the camera
commands
.spawn()
.insert_bundle(OrthographicCameraBundle::new_2d())
.insert(Transform::from_xyz(0.0, 0.0, 1000.0));
// Builds and spawns the sprites
let mut sprites = vec![];
for y in -half_y..half_y {
for x in -half_x..half_x {
let position = Vec2::new(x as f32, y as f32);
let translation = (position * tile_size).extend(rng.gen::<f32>());
let rotation = Quat::from_rotation_z(rng.gen::<f32>());
let scale = Vec3::splat(rng.gen::<f32>() * 2.0);
sprites.push(SpriteBundle {
texture: sprite_handle.clone(),
transform: Transform {
translation,
rotation,
scale,
},
sprite: Sprite {
custom_size: Some(tile_size),
..default()
},
..default()
});
}
}
commands.spawn_batch(sprites);
}
// System for rotating and translating the camera
fn move_camera(time: Res<Time>, mut camera_query: Query<&mut Transform, With<Camera>>) {
let mut camera_transform = camera_query.single_mut();
camera_transform.rotate(Quat::from_rotation_z(time.delta_seconds() * 0.5));
*camera_transform = *camera_transform
* Transform::from_translation(Vec3::X * CAMERA_SPEED * time.delta_seconds());
}
#[derive(Deref, DerefMut)]
struct PrintingTimer(Timer);
impl Default for PrintingTimer {
fn default() -> Self {
Self(Timer::from_seconds(1.0, true))
}
}
// System for printing the number of sprites on every tick of the timer
fn print_sprite_count(time: Res<Time>, mut timer: Local<PrintingTimer>, sprites: Query<&Sprite>) {
timer.tick(time.delta());
if timer.just_finished() {
info!("Sprites: {}", sprites.iter().count(),);
}
}