bevy/examples/2d/texture_atlas.rs
Rob Parrett a788e31ad5
Fix CI for Rust 1.72 (#9562)
# Objective

[Rust 1.72.0](https://blog.rust-lang.org/2023/08/24/Rust-1.72.0.html) is
now stable.

# Notes

- `let-else` formatting has arrived!
- I chose to allow `explicit_iter_loop` due to
https://github.com/rust-lang/rust-clippy/issues/11074.
  
We didn't hit any of the false positives that prevent compilation, but
fixing this did produce a lot of the "symbol soup" mentioned, e.g. `for
image in &mut *image_events {`.
  
  Happy to undo this if there's consensus the other way.

---------

Co-authored-by: François <mockersf@gmail.com>
2023-08-25 12:34:24 +00:00

95 lines
3.2 KiB
Rust

//! In this example we generate a new texture atlas (sprite sheet) from a folder containing
//! individual sprites.
use bevy::{asset::LoadState, prelude::*};
fn main() {
App::new()
.init_resource::<RpgSpriteHandles>()
.add_plugins(DefaultPlugins.set(ImagePlugin::default_nearest())) // prevents blurry sprites
.add_state::<AppState>()
.add_systems(OnEnter(AppState::Setup), load_textures)
.add_systems(Update, check_textures.run_if(in_state(AppState::Setup)))
.add_systems(OnEnter(AppState::Finished), setup)
.run();
}
#[derive(Debug, Clone, Copy, Default, PartialEq, Eq, Hash, States)]
enum AppState {
#[default]
Setup,
Finished,
}
#[derive(Resource, Default)]
struct RpgSpriteHandles {
handles: Vec<HandleUntyped>,
}
fn load_textures(mut rpg_sprite_handles: ResMut<RpgSpriteHandles>, asset_server: Res<AssetServer>) {
// load multiple, individual sprites from a folder
rpg_sprite_handles.handles = asset_server.load_folder("textures/rpg").unwrap();
}
fn check_textures(
mut next_state: ResMut<NextState<AppState>>,
rpg_sprite_handles: ResMut<RpgSpriteHandles>,
asset_server: Res<AssetServer>,
) {
// Advance the `AppState` once all sprite handles have been loaded by the `AssetServer`
if let LoadState::Loaded = asset_server
.get_group_load_state(rpg_sprite_handles.handles.iter().map(|handle| handle.id()))
{
next_state.set(AppState::Finished);
}
}
fn setup(
mut commands: Commands,
rpg_sprite_handles: Res<RpgSpriteHandles>,
asset_server: Res<AssetServer>,
mut texture_atlases: ResMut<Assets<TextureAtlas>>,
mut textures: ResMut<Assets<Image>>,
) {
// Build a `TextureAtlas` using the individual sprites
let mut texture_atlas_builder = TextureAtlasBuilder::default();
for handle in &rpg_sprite_handles.handles {
let handle = handle.typed_weak();
let Some(texture) = textures.get(&handle) else {
warn!(
"{:?} did not resolve to an `Image` asset.",
asset_server.get_handle_path(handle)
);
continue;
};
texture_atlas_builder.add_texture(handle, texture);
}
let texture_atlas = texture_atlas_builder.finish(&mut textures).unwrap();
let texture_atlas_texture = texture_atlas.texture.clone();
let vendor_handle = asset_server.get_handle("textures/rpg/chars/vendor/generic-rpg-vendor.png");
let vendor_index = texture_atlas.get_texture_index(&vendor_handle).unwrap();
let atlas_handle = texture_atlases.add(texture_atlas);
// set up a scene to display our texture atlas
commands.spawn(Camera2dBundle::default());
// draw a sprite from the atlas
commands.spawn(SpriteSheetBundle {
transform: Transform {
translation: Vec3::new(150.0, 0.0, 0.0),
scale: Vec3::splat(4.0),
..default()
},
sprite: TextureAtlasSprite::new(vendor_index),
texture_atlas: atlas_handle,
..default()
});
// draw the atlas itself
commands.spawn(SpriteBundle {
texture: texture_atlas_texture,
transform: Transform::from_xyz(-300.0, 0.0, 0.0),
..default()
});
}