31bd4ecbbc
# Objective Load skeletal weights and indices from GLTF files. Animate meshes. ## Solution - Load skeletal weights and indices from GLTF files. - Added `SkinnedMesh` component and ` SkinnedMeshInverseBindPose` asset - Added `extract_skinned_meshes` to extract joint matrices. - Added queue phase systems for enqueuing the buffer writes. Some notes: - This ports part of # #2359 to the current main. - This generates new `BufferVec`s and bind groups every frame. The expectation here is that the number of `Query::get` calls during extract is probably going to be the stronger bottleneck, with up to 256 calls per skinned mesh. Until that is optimized, caching buffers and bind groups is probably a non-concern. - Unfortunately, due to the uniform size requirements, this means a 16KB buffer is allocated for every skinned mesh every frame. There's probably a few ways to get around this, but most of them require either compute shaders or storage buffers, which are both incompatible with WebGL2. Co-authored-by: james7132 <contact@jamessliu.com> Co-authored-by: François <mockersf@gmail.com> Co-authored-by: James Liu <contact@jamessliu.com>
71 lines
2.6 KiB
Rust
71 lines
2.6 KiB
Rust
use std::f32::consts::PI;
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use bevy::{pbr::AmbientLight, prelude::*, render::mesh::skinning::SkinnedMesh};
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/// Skinned mesh example with mesh and joints data loaded from a glTF file.
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/// Example taken from <https://github.com/KhronosGroup/glTF-Tutorials/blob/master/gltfTutorial/gltfTutorial_019_SimpleSkin.md>
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fn main() {
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App::new()
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.add_plugins(DefaultPlugins)
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.insert_resource(AmbientLight {
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brightness: 1.0,
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..Default::default()
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})
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.add_startup_system(setup)
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.add_system(joint_animation)
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.run();
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}
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fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
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// Create a camera
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commands.spawn_bundle(PerspectiveCameraBundle {
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transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
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..default()
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});
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// Spawn the first scene in `models/SimpleSkin/SimpleSkin.gltf`
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commands.spawn_scene(asset_server.load::<Scene, _>("models/SimpleSkin/SimpleSkin.gltf#Scene0"));
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}
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/// The scene hierachy currently looks somewhat like this:
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///
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/// ```ignore
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/// <Parent entity>
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/// + Mesh node (without `PbrBundle` or `SkinnedMesh` component)
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/// + Skinned mesh entity (with `PbrBundle` and `SkinnedMesh` component, created by glTF loader)
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/// + First joint
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/// + Second joint
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/// ```
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///
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/// In this example, we want to get and animate the second joint.
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/// It is similar to the animation defined in `models/SimpleSkin/SimpleSkin.gltf`.
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fn joint_animation(
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time: Res<Time>,
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parent_query: Query<&Parent, With<SkinnedMesh>>,
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children_query: Query<&Children>,
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mut transform_query: Query<&mut Transform>,
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) {
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// Iter skinned mesh entity
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for skinned_mesh_parent in parent_query.iter() {
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// Mesh node is the parent of the skinned mesh entity.
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let mesh_node_entity = skinned_mesh_parent.0;
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// Get `Children` in the mesh node.
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let mesh_node_children = children_query.get(mesh_node_entity).unwrap();
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// First joint is the second child of the mesh node.
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let first_joint_entity = mesh_node_children[1];
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// Get `Children` in the first joint.
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let first_joint_children = children_query.get(first_joint_entity).unwrap();
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// Second joint is the first child of the first joint.
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let second_joint_entity = first_joint_children[0];
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// Get `Transform` in the second joint.
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let mut second_joint_transform = transform_query.get_mut(second_joint_entity).unwrap();
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second_joint_transform.rotation = Quat::from_axis_angle(
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Vec3::Z,
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0.5 * PI * time.time_since_startup().as_secs_f32().sin(),
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);
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}
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}
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