use std::f32::consts::*;
use bevy::{
pbr::AmbientLight,
prelude::*,
render::mesh::{
skinning::{SkinnedMesh, SkinnedMeshInverseBindposes},
Indices, PrimitiveTopology, VertexAttributeValues,
},
};
use rand::Rng;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.insert_resource(AmbientLight {
brightness: 1.0,
..default()
})
.add_systems(Startup, setup)
.add_systems(Update, joint_animation)
.run();
}
#[derive(Component)]
struct AnimatedJoint;
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
mut skinned_mesh_inverse_bindposes_assets: ResMut<Assets<SkinnedMeshInverseBindposes>>,
) {
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
});
let inverse_bindposes =
skinned_mesh_inverse_bindposes_assets.add(SkinnedMeshInverseBindposes::from(vec![
Mat4::from_translation(Vec3::new(-0.5, -1.0, 0.0)),
Mat4::from_translation(Vec3::new(-0.5, -1.0, 0.0)),
]));
let mut mesh = Mesh::new(PrimitiveTopology::TriangleList);
mesh.insert_attribute(
Mesh::ATTRIBUTE_POSITION,
vec![
[0.0, 0.0, 0.0],
[1.0, 0.0, 0.0],
[0.0, 0.5, 0.0],
[1.0, 0.5, 0.0],
[0.0, 1.0, 0.0],
[1.0, 1.0, 0.0],
[0.0, 1.5, 0.0],
[1.0, 1.5, 0.0],
[0.0, 2.0, 0.0],
[1.0, 2.0, 0.0],
],
);
mesh.insert_attribute(Mesh::ATTRIBUTE_NORMAL, vec![[0.0, 0.0, 1.0]; 10]);
mesh.insert_attribute(
Mesh::ATTRIBUTE_JOINT_INDEX,
VertexAttributeValues::Uint16x4(vec![
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
[0, 1, 0, 0],
]),
);
mesh.insert_attribute(
Mesh::ATTRIBUTE_JOINT_WEIGHT,
vec![
[1.00, 0.00, 0.0, 0.0],
[1.00, 0.00, 0.0, 0.0],
[0.75, 0.25, 0.0, 0.0],
[0.75, 0.25, 0.0, 0.0],
[0.50, 0.50, 0.0, 0.0],
[0.50, 0.50, 0.0, 0.0],
[0.25, 0.75, 0.0, 0.0],
[0.25, 0.75, 0.0, 0.0],
[0.00, 1.00, 0.0, 0.0],
[0.00, 1.00, 0.0, 0.0],
],
);
mesh.set_indices(Some(Indices::U16(vec![
0, 1, 3, 0, 3, 2, 2, 3, 5, 2, 5, 4, 4, 5, 7, 4, 7, 6, 6, 7, 9, 6, 9, 8,
])));
let mesh = meshes.add(mesh);
for i in -5..5 {
let joint_0 = commands
.spawn(TransformBundle::from(Transform::from_xyz(
i as f32 * 1.5,
0.0,
0.0,
)))
.id();
let joint_1 = commands
.spawn((AnimatedJoint, TransformBundle::IDENTITY))
.id();
commands.entity(joint_0).push_children(&[joint_1]);
let joint_entities = vec![joint_0, joint_1];
commands.spawn((
PbrBundle {
mesh: mesh.clone(),
material: materials.add(
Color::rgb(
rand::thread_rng().gen_range(0.0..1.0),
rand::thread_rng().gen_range(0.0..1.0),
rand::thread_rng().gen_range(0.0..1.0),
)
.into(),
),
..default()
},
SkinnedMesh {
inverse_bindposes: inverse_bindposes.clone(),
joints: joint_entities,
},
));
}
}
fn joint_animation(time: Res<Time>, mut query: Query<&mut Transform, With<AnimatedJoint>>) {
for mut transform in &mut query {
transform.rotation = Quat::from_rotation_z(FRAC_PI_2 * time.elapsed_seconds().sin());
}
}