bevy/examples/asset/hot_asset_reloading.rs
Tim eb51b4c28e
Migrate scenes to required components (#15579)
# Objective

A step in the migration to required components: scenes!

## Solution

As per the [selected
proposal](https://hackmd.io/@bevy/required_components/%2FPJtNGVMMQhyM0zIvCJSkbA):
- Deprecate `SceneBundle` and `DynamicSceneBundle`.
- Add `SceneRoot` and `DynamicSceneRoot` components, which wrap a
`Handle<Scene>` and `Handle<DynamicScene>` respectively.

## Migration Guide
Asset handles for scenes and dynamic scenes must now be wrapped in the
`SceneRoot` and `DynamicSceneRoot` components. Raw handles as components
no longer spawn scenes.

Additionally, `SceneBundle` and `DynamicSceneBundle` have been
deprecated. Instead, use the scene components directly.

Previously:
```rust
let model_scene = asset_server.load(GltfAssetLabel::Scene(0).from_asset("model.gltf"));

commands.spawn(SceneBundle {
    scene: model_scene,
    transform: Transform::from_xyz(-4.0, 0.0, -3.0),
    ..default()
});
```
Now:
```rust
let model_scene = asset_server.load(GltfAssetLabel::Scene(0).from_asset("model.gltf"));

commands.spawn((
    SceneRoot(model_scene),
    Transform::from_xyz(-4.0, 0.0, -3.0),
));
```
2024-10-01 22:42:11 +00:00

38 lines
1.3 KiB
Rust

//! Hot reloading allows you to modify assets files to be immediately reloaded while your game is
//! running. This lets you immediately see the results of your changes without restarting the game.
//! This example illustrates hot reloading mesh changes.
//!
//! Note that hot asset reloading requires the [`AssetWatcher`](bevy::asset::io::AssetWatcher) to be enabled
//! for your current platform. For desktop platforms, enable the `file_watcher` cargo feature.
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
// Load our mesh:
let scene_handle =
asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/torus/torus.gltf"));
// Any changes to the mesh will be reloaded automatically! Try making a change to torus.gltf.
// You should see the changes immediately show up in your app.
// mesh
commands.spawn(SceneRoot(scene_handle));
// light
commands.spawn((
DirectionalLight::default(),
Transform::from_xyz(4.0, 5.0, 4.0).looking_at(Vec3::ZERO, Vec3::Y),
));
// camera
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(2.0, 2.0, 6.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
});
}