bevy/examples/shader/shader_material_screenspace_texture.rs
Carter Anderson dcc03724a5 Base Sets (#7466)
# Objective

NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267.

"Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365).

## Solution

This adds "base sets" as a variant of `SystemSet`:

A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive:

```rust
#[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)]
#[system_set(base)]
enum MyBaseSet {
  A,
  B,
}
``` 

**Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build. 

**Base sets cannot belong to other sets**: this is where the word "base" comes from

Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set.

```rust
app.add_system(foo.in_base_set(MyBaseSet::A))
       // X must be a normal set ... base sets cannot be added to base sets
       .configure_set(X.in_base_set(MyBaseSet::A))
```

Base sets can still be configured like normal sets:

```rust
app.add_system(MyBaseSet::B.after(MyBaseSet::Ap))
``` 

The primary use case for base sets is enabling a "default base set":

```rust
schedule.set_default_base_set(CoreSet::Update)
  // this will belong to CoreSet::Update by default
  .add_system(foo)
  // this will override the default base set with PostUpdate
  .add_system(bar.in_base_set(CoreSet::PostUpdate))
```

This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides.

---

## Changelog

- Added "base sets" and ported CoreSet to use them.

## Migration Guide

TODO
2023-02-06 03:10:08 +00:00

82 lines
2.3 KiB
Rust

//! A shader that samples a texture with view-independent UV coordinates.
use bevy::{
prelude::*,
reflect::TypeUuid,
render::render_resource::{AsBindGroup, ShaderRef},
};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_plugin(MaterialPlugin::<CustomMaterial>::default())
.add_startup_system(setup)
.add_system(rotate_camera)
.run();
}
#[derive(Component)]
struct MainCamera;
fn setup(
mut commands: Commands,
asset_server: Res<AssetServer>,
mut meshes: ResMut<Assets<Mesh>>,
mut custom_materials: ResMut<Assets<CustomMaterial>>,
mut standard_materials: ResMut<Assets<StandardMaterial>>,
) {
commands.spawn(PbrBundle {
mesh: meshes.add(Mesh::from(shape::Plane { size: 5.0 })),
material: standard_materials.add(Color::rgb(0.3, 0.5, 0.3).into()),
..default()
});
commands.spawn(PointLightBundle {
transform: Transform::from_xyz(4.0, 8.0, 4.0),
..default()
});
commands.spawn(MaterialMeshBundle {
mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
transform: Transform::from_xyz(0.0, 0.5, 0.0),
material: custom_materials.add(CustomMaterial {
texture: asset_server.load(
"models/FlightHelmet/FlightHelmet_Materials_LensesMat_OcclusionRoughMetal.png",
),
}),
..default()
});
// camera
commands.spawn((
Camera3dBundle {
transform: Transform::from_xyz(4.0, 2.5, 4.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
},
MainCamera,
));
}
fn rotate_camera(mut camera: Query<&mut Transform, With<MainCamera>>, time: Res<Time>) {
let cam_transform = camera.single_mut().into_inner();
cam_transform.rotate_around(
Vec3::ZERO,
Quat::from_axis_angle(Vec3::Y, 45f32.to_radians() * time.delta_seconds()),
);
cam_transform.look_at(Vec3::ZERO, Vec3::Y);
}
#[derive(AsBindGroup, Debug, Clone, TypeUuid)]
#[uuid = "b62bb455-a72c-4b56-87bb-81e0554e234f"]
pub struct CustomMaterial {
#[texture(0)]
#[sampler(1)]
texture: Handle<Image>,
}
impl Material for CustomMaterial {
fn fragment_shader() -> ShaderRef {
"shaders/custom_material_screenspace_texture.wgsl".into()
}
}