WIP Blendshapes (#45)

* WIP Blendshapes

* Greatly overhauled how code works

* Stripped almost everything out and simplified code

---------

Co-authored-by: Ryan Butler <thebutlah@gmail.com>

.gitignore

@@ -4,3 +4,4 @@
 .idea
 .envrc
 .direnv
+.vscode

Cargo.toml

@@ -8,6 +8,7 @@ members = [
  "skills/openxr-6dof",
  "skills/xr-ik-mirror",
  "skills/entity-inspector",
+ "skills/blendshapes",
 ]
 
 # These settings will apply to all members of the workspace that opt in to them

skills/blendshapes/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "blendshapes"
+version.workspace = true
+license.workspace = true
+repository.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+bevy.workspace = true

skills/blendshapes/README.md

@@ -0,0 +1,9 @@
+# Blendshapes and Morph Targets
+
+Demonstrates how to use morph targets to animate the blend shapes. For example
+to make a gltf avatar blink.
+
+To run the code:
+```bash
+cargo run -p blendshapes
+```

skills/blendshapes/src/main.rs

@@ -0,0 +1,64 @@
+use bevy::prelude::*;
+
+/// The blendshape/morph target corresponding to a blink is at this index
+const BLINK_MORPH_IDX: usize = 13;
+const FACE_ENTITY_NAME: &str = "Face";
+const ASSET_FOLDER: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../assets/");
+
+fn main() {
+ // This will take like 5 seconds to load the gltf/vrm model, don't worry, just wait.
+ App::new()
+ .insert_resource(AmbientLight {
+ color: Color::WHITE,
+ brightness: 1.0 / 5.0f32,
+ })
+ .add_plugins(DefaultPlugins.set(AssetPlugin {
+ file_path: ASSET_FOLDER.to_string(),
+ ..default()
+ }))
+ .add_systems(Startup, setup)
+ .add_systems(Update, animate_blink)
+ .run()
+}
+
+fn setup(mut commands: Commands, assets: Res<AssetServer>) {
+ commands
+ .spawn(SpatialBundle::default())
+ .with_children(|parent| {
+ parent.spawn(Camera3dBundle {
+ transform: Transform::from_xyz(0.0, 1.45, 0.5)
+ .looking_at(Vec3::new(0.0, 1.45, 0.0), Vec3::Y),
+ projection: bevy::render::camera::Projection::Perspective(
+ PerspectiveProjection {
+ fov: std::f32::consts::FRAC_PI_4,
+ aspect_ratio: 1.0,
+ near: 0.1,
+ far: 100.0,
+ },
+ ),
+ ..default()
+ });
+ });
+
+ commands.spawn(SceneBundle {
+ scene: assets.load("malek.gltf#Scene0"),
+ transform: Transform::from_xyz(0.0, 0.0, 0.0).with_rotation(Quat::from_euler(
+ EulerRot::XYZ,
+ 0.0,
+ 180.0_f32.to_radians(),
+ 0.0,
+ )),
+ ..default()
+ });
+}
+
+fn animate_blink(mut morphs: Query<(&Name, &mut MorphWeights)>, time: Res<Time>) {
+ let Some((_, mut weights)) = morphs
+ .iter_mut()
+ .find(|(name, _)| name.as_str() == FACE_ENTITY_NAME)
+ else {
+ return;
+ };
+ weights.weights_mut()[BLINK_MORPH_IDX] =
+ (f32::sin(time.elapsed_seconds() * 10.0) + 1.) / 2.;
+}