use bevy::gltf::GltfPlugin;
use bevy::prelude::*;
use bevy::reflect::{TypePath, TypeUuid};
use bevy::render::mesh::{MeshVertexAttribute, MeshVertexBufferLayout};
use bevy::render::render_resource::*;
use bevy::sprite::{
Material2d, Material2dKey, Material2dPlugin, MaterialMesh2dBundle, Mesh2dHandle,
};
const ATTRIBUTE_BARYCENTRIC: MeshVertexAttribute =
MeshVertexAttribute::new("Barycentric", 2137464976, VertexFormat::Float32x3);
fn main() {
App::new()
.insert_resource(AmbientLight {
color: Color::WHITE,
brightness: 1.0 / 5.0f32,
})
.add_plugins((
DefaultPlugins.set(
GltfPlugin::default()
.add_custom_vertex_attribute("_BARYCENTRIC", ATTRIBUTE_BARYCENTRIC),
),
Material2dPlugin::<CustomMaterial>::default(),
))
.add_systems(Startup, setup)
.run();
}
fn setup(
mut commands: Commands,
asset_server: Res<AssetServer>,
mut materials: ResMut<Assets<CustomMaterial>>,
) {
let mesh = asset_server.load("models/barycentric/barycentric.gltf#Mesh0/Primitive0");
commands.spawn(MaterialMesh2dBundle {
mesh: Mesh2dHandle(mesh),
material: materials.add(CustomMaterial {}),
transform: Transform::from_scale(150.0 * Vec3::ONE),
..default()
});
commands.spawn(Camera2dBundle { ..default() });
}
#[derive(AsBindGroup, TypeUuid, TypePath, Debug, Clone)]
#[uuid = "50ffce9e-1582-42e9-87cb-2233724426c0"]
struct CustomMaterial {}
impl Material2d for CustomMaterial {
fn fragment_shader() -> ShaderRef {
"shaders/custom_gltf_2d.wgsl".into()
}
fn vertex_shader() -> ShaderRef {
"shaders/custom_gltf_2d.wgsl".into()
}
fn specialize(
descriptor: &mut RenderPipelineDescriptor,
layout: &MeshVertexBufferLayout,
_key: Material2dKey<Self>,
) -> Result<(), SpecializedMeshPipelineError> {
let vertex_layout = layout.get_layout(&[
Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
Mesh::ATTRIBUTE_COLOR.at_shader_location(1),
ATTRIBUTE_BARYCENTRIC.at_shader_location(2),
])?;
descriptor.vertex.buffers = vec![vertex_layout];
Ok(())
}
}