bevy/examples/shader/array_texture.rs
Kornel 435d9bc02c
Highlight dependency on shader files in examples (#13824)
The examples won't work when copy-pasted to another project, without
also copying their shader files. This change adds constants at the top
of the files to bring attention to the dependencies.

Follow up to
[#13624](https://github.com/bevyengine/bevy/pull/13624#issuecomment-2143872791)
2024-06-12 14:16:01 +00:00

97 lines
2.8 KiB
Rust

//! This example illustrates how to create a texture for use with a `texture_2d_array<f32>` shader
//! uniform variable.
use bevy::{
asset::LoadState,
prelude::*,
reflect::TypePath,
render::render_resource::{AsBindGroup, ShaderRef},
};
/// This example uses a shader source file from the assets subdirectory
const SHADER_ASSET_PATH: &str = "shaders/array_texture.wgsl";
fn main() {
App::new()
.add_plugins((
DefaultPlugins,
MaterialPlugin::<ArrayTextureMaterial>::default(),
))
.add_systems(Startup, setup)
.add_systems(Update, create_array_texture)
.run();
}
#[derive(Resource)]
struct LoadingTexture {
is_loaded: bool,
handle: Handle<Image>,
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
// Start loading the texture.
commands.insert_resource(LoadingTexture {
is_loaded: false,
handle: asset_server.load("textures/array_texture.png"),
});
// light
commands.spawn(DirectionalLightBundle {
transform: Transform::from_xyz(3.0, 2.0, 1.0).looking_at(Vec3::ZERO, Vec3::Y),
..Default::default()
});
// camera
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(5.0, 5.0, 5.0).looking_at(Vec3::new(1.5, 0.0, 0.0), Vec3::Y),
..Default::default()
});
}
fn create_array_texture(
mut commands: Commands,
asset_server: Res<AssetServer>,
mut loading_texture: ResMut<LoadingTexture>,
mut images: ResMut<Assets<Image>>,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<ArrayTextureMaterial>>,
) {
if loading_texture.is_loaded
|| asset_server.load_state(loading_texture.handle.id()) != LoadState::Loaded
{
return;
}
loading_texture.is_loaded = true;
let image = images.get_mut(&loading_texture.handle).unwrap();
// Create a new array texture asset from the loaded texture.
let array_layers = 4;
image.reinterpret_stacked_2d_as_array(array_layers);
// Spawn some cubes using the array texture
let mesh_handle = meshes.add(Cuboid::default());
let material_handle = materials.add(ArrayTextureMaterial {
array_texture: loading_texture.handle.clone(),
});
for x in -5..=5 {
commands.spawn(MaterialMeshBundle {
mesh: mesh_handle.clone(),
material: material_handle.clone(),
transform: Transform::from_xyz(x as f32 + 0.5, 0.0, 0.0),
..Default::default()
});
}
}
#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
struct ArrayTextureMaterial {
#[texture(0, dimension = "2d_array")]
#[sampler(1)]
array_texture: Handle<Image>,
}
impl Material for ArrayTextureMaterial {
fn fragment_shader() -> ShaderRef {
SHADER_ASSET_PATH.into()
}
}