Fixes #17412 ## Objective `Parent` uses the "has a X" naming convention. There is increasing sentiment that we should use the "is a X" naming convention for relationships (following #17398). This leaves `Children` as-is because there is prevailing sentiment that `Children` is clearer than `ParentOf` in many cases (especially when treating it like a collection). This renames `Parent` to `ChildOf`. This is just the implementation PR. To discuss the path forward, do so in #17412. ## Migration Guide - The `Parent` component has been renamed to `ChildOf`.
		
			
				
	
	
		
			72 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! Skinned mesh example with mesh and joints data loaded from a glTF file.
 | 
						|
//! Example taken from <https://github.com/KhronosGroup/glTF-Tutorials/blob/master/gltfTutorial/gltfTutorial_019_SimpleSkin.md>
 | 
						|
 | 
						|
use std::f32::consts::*;
 | 
						|
 | 
						|
use bevy::{math::ops, prelude::*, render::mesh::skinning::SkinnedMesh};
 | 
						|
 | 
						|
fn main() {
 | 
						|
    App::new()
 | 
						|
        .add_plugins(DefaultPlugins)
 | 
						|
        .insert_resource(AmbientLight {
 | 
						|
            brightness: 750.0,
 | 
						|
            ..default()
 | 
						|
        })
 | 
						|
        .add_systems(Startup, setup)
 | 
						|
        .add_systems(Update, joint_animation)
 | 
						|
        .run();
 | 
						|
}
 | 
						|
 | 
						|
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
 | 
						|
    // Create a camera
 | 
						|
    commands.spawn((
 | 
						|
        Camera3d::default(),
 | 
						|
        Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::new(0.0, 1.0, 0.0), Vec3::Y),
 | 
						|
    ));
 | 
						|
 | 
						|
    // Spawn the first scene in `models/SimpleSkin/SimpleSkin.gltf`
 | 
						|
    commands.spawn(SceneRoot(asset_server.load(
 | 
						|
        GltfAssetLabel::Scene(0).from_asset("models/SimpleSkin/SimpleSkin.gltf"),
 | 
						|
    )));
 | 
						|
}
 | 
						|
 | 
						|
/// The scene hierarchy currently looks somewhat like this:
 | 
						|
///
 | 
						|
/// ```text
 | 
						|
/// <Parent entity>
 | 
						|
///   + Mesh node (without `Mesh3d` or `SkinnedMesh` component)
 | 
						|
///     + Skinned mesh entity (with `Mesh3d` and `SkinnedMesh` component, created by glTF loader)
 | 
						|
///     + First joint
 | 
						|
///       + Second joint
 | 
						|
/// ```
 | 
						|
///
 | 
						|
/// In this example, we want to get and animate the second joint.
 | 
						|
/// It is similar to the animation defined in `models/SimpleSkin/SimpleSkin.gltf`.
 | 
						|
fn joint_animation(
 | 
						|
    time: Res<Time>,
 | 
						|
    children: Query<&ChildOf, With<SkinnedMesh>>,
 | 
						|
    parents: Query<&Children>,
 | 
						|
    mut transform_query: Query<&mut Transform>,
 | 
						|
) {
 | 
						|
    // Iter skinned mesh entity
 | 
						|
    for child_of in &children {
 | 
						|
        // Mesh node is the parent of the skinned mesh entity.
 | 
						|
        let mesh_node_entity = child_of.get();
 | 
						|
        // Get `Children` in the mesh node.
 | 
						|
        let mesh_node_parent = parents.get(mesh_node_entity).unwrap();
 | 
						|
 | 
						|
        // First joint is the second child of the mesh node.
 | 
						|
        let first_joint_entity = mesh_node_parent[1];
 | 
						|
        // Get `Children` in the first joint.
 | 
						|
        let first_joint_children = parents.get(first_joint_entity).unwrap();
 | 
						|
 | 
						|
        // Second joint is the first child of the first joint.
 | 
						|
        let second_joint_entity = first_joint_children[0];
 | 
						|
        // Get `Transform` in the second joint.
 | 
						|
        let mut second_joint_transform = transform_query.get_mut(second_joint_entity).unwrap();
 | 
						|
 | 
						|
        second_joint_transform.rotation =
 | 
						|
            Quat::from_rotation_z(FRAC_PI_2 * ops::sin(time.elapsed_secs()));
 | 
						|
    }
 | 
						|
}
 |