docs/bevy/examples/shader/shader_material_2d_bindless.rs 3 K · 103 lines · raw · history

1 //! Demonstrates bindless materials in 2D.
2
3 use bevy::{
4 prelude::*,
5 reflect::TypePath,
6 render::render_resource::{AsBindGroup, ShaderType},
7 shader::ShaderRef,
8 sprite_render::{AlphaMode2d, Material2d, Material2dPlugin},
9 };
10
11 /// This example uses a shader source file from the `assets` subdirectory.
12 const SHADER_ASSET_PATH: &str = "shaders/custom_material_2d_bindless.wesl";
13
14 fn main() {
15 App::new()
16 .add_plugins((
17 DefaultPlugins,
18 Material2dPlugin::<BindlessMaterial>::default(),
19 ))
20 .add_systems(Startup, setup)
21 .run();
22 }
23
24 // Setup a simple 2D scene.
25 fn setup(
26 mut commands: Commands,
27 mut meshes: ResMut<Assets<Mesh>>,
28 mut materials: ResMut<Assets<BindlessMaterial>>,
29 asset_server: Res<AssetServer>,
30 ) {
31 // Spawn the camera.
32 commands.spawn(Camera2d);
33
34 // Create the shared assets that the bindless material will use.
35 let dark_icon = asset_server.load("branding/bevy_logo_dark.png");
36 let light_icon = asset_server.load("branding/bevy_logo_light.png");
37 let mesh = meshes.add(Rectangle::default());
38
39 // Spawn the quads.
40 for (offset, color, image) in [
41 (vec2(-1.0, -1.0), LinearRgba::RED, dark_icon.clone()),
42 (
43 vec2(1.0, -1.0),
44 LinearRgba::new(1.0, 1.0, 0.0, 1.0),
45 light_icon.clone(),
46 ),
47 (vec2(-1.0, 1.0), LinearRgba::GREEN, dark_icon.clone()),
48 (vec2(1.0, 1.0), LinearRgba::BLUE, light_icon.clone()),
49 ] {
50 commands.spawn((
51 Mesh2d(mesh.clone()),
52 MeshMaterial2d(materials.add(BindlessMaterial {
53 color,
54 color_texture: Some(image),
55 })),
56 Transform::default()
57 .with_scale(vec3(128.0, 32.0, 1.0))
58 .with_translation((offset * 128.0).extend(0.0)),
59 ));
60 }
61 }
62
63 /// The CPU-side structure that's passed to the shader.
64 #[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
65 #[uniform(0, BindlessMaterialUniform, binding_array(10))]
66 #[bindless]
67 struct BindlessMaterial {
68 color: LinearRgba,
69 #[texture(1)]
70 #[sampler(2)]
71 color_texture: Option<Handle<Image>>,
72 }
73
74 /// The GPU-side structure that's passed to the shader.
75 #[derive(ShaderType)]
76 struct BindlessMaterialUniform {
77 color: LinearRgba,
78 }
79
80 // The conversion function that Bevy calls to convert from the CPU-side material
81 // structure to the GPU-side material structure.
82 impl<'a> From<&'a BindlessMaterial> for BindlessMaterialUniform {
83 fn from(material: &'a BindlessMaterial) -> Self {
84 BindlessMaterialUniform {
85 color: material.color,
86 }
87 }
88 }
89
90 // The `Material2d`` trait is very configurable, but comes with sensible defaults
91 // for all methods.
92 //
93 // You only need to implement functions for features that need non-default
94 // behavior. See the `Material2d` API documentation for details.
95 impl Material2d for BindlessMaterial {
96 fn fragment_shader() -> ShaderRef {
97 SHADER_ASSET_PATH.into()
98 }
99
100 fn alpha_mode(&self) -> AlphaMode2d {
101 AlphaMode2d::Mask(0.5)
102 }
103 }