Struct bevy::render::mesh::morph::MorphWeights

pub struct MorphWeights { /* private fields */ }

Expand description

Controls the morph targets for all child Handle<Mesh> entities. In most cases, MorphWeights should be considered the “source of truth” when writing morph targets for meshes. However you can choose to write child MeshMorphWeights if your situation requires more granularity. Just note that if you set MorphWeights, it will overwrite child MeshMorphWeights values.

This exists because Bevy’s Mesh corresponds to a single surface / material, whereas morph targets as defined in the GLTF spec exist on “multi-primitive meshes” (where each primitive is its own surface with its own material). Therefore in Bevy MorphWeights an a parent entity are the “canonical weights” from a GLTF perspective, which then synchronized to child Handle<Mesh> / MeshMorphWeights (which correspond to “primitives” / “surfaces” from a GLTF perspective).

Add this to the parent of one or more Entities with a Handle<Mesh> with a MeshMorphWeights.

Implementations§

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impl MorphWeights

pub fn new( weights: Vec<f32>, first_mesh: Option<Handle<Mesh>> ) -> Result<MorphWeights, MorphBuildError>

pub fn first_mesh(&self) -> Option<&Handle<Mesh>>

The first child Handle<Mesh> primitive controlled by these weights. This can be used to look up metadata information such as Mesh::morph_target_names.

Examples found in repository ?

examples/tools/scene_viewer/morph_viewer_plugin.rs (line 250)

fn detect_morphs(
    mut commands: Commands,
    morphs: Query<(Entity, &MorphWeights, Option<&Name>)>,
    meshes: Res<Assets<Mesh>>,
    scene_handle: Res<SceneHandle>,
    mut setup: Local<bool>,
    asset_server: Res<AssetServer>,
) {
    let no_morphing = morphs.iter().len() == 0;
    if no_morphing {
        return;
    }
    if scene_handle.is_loaded && !*setup {
        *setup = true;
    } else {
        return;
    }
    let mut detected = Vec::new();

    for (entity, weights, name) in &morphs {
        let target_names = weights
            .first_mesh()
            .and_then(|h| meshes.get(h))
            .and_then(|m| m.morph_target_names());
        let targets = Target::new(name, weights.weights(), target_names, entity);
        detected.extend(targets);
    }
    detected.truncate(AVAILABLE_KEYS.len());
    let style = TextStyle {
        font: asset_server.load("assets/fonts/FiraMono-Medium.ttf"),
        font_size: 13.0,
        ..default()
    };
    let mut sections = vec![
        TextSection::new("Morph Target Controls\n", style.clone()),
        TextSection::new("---------------\n", style.clone()),
    ];
    let target_to_text =
        |(i, target): (usize, &Target)| target.text_section(AVAILABLE_KEYS[i].name, style.clone());
    sections.extend(detected.iter().enumerate().map(target_to_text));
    commands.insert_resource(WeightsControl { weights: detected });
    commands.spawn(TextBundle::from_sections(sections).with_style(Style {
        position_type: PositionType::Absolute,
        top: Val::Px(10.0),
        left: Val::Px(10.0),
        ..default()
    }));
}

pub fn weights(&self) -> &[f32]

Examples found in repository ?

examples/tools/scene_viewer/morph_viewer_plugin.rs (line 191)

fn update_text(
    controls: Option<ResMut<WeightsControl>>,
    mut text: Query<&mut Text>,
    morphs: Query<&MorphWeights>,
) {
    let Some(mut controls) = controls else {
        return;
    };
    for (i, target) in controls.weights.iter_mut().enumerate() {
        let Ok(weights) = morphs.get(target.entity) else {
            continue;
        };
        let Some(&actual_weight) = weights.weights().get(target.index) else {
            continue;
        };
        if actual_weight != target.weight {
            target.weight = actual_weight;
        }
        let key_name = &AVAILABLE_KEYS[i].name;
        let mut text = text.single_mut();
        text.sections[i + 2].value = format!("[{key_name}] {target}\n");
    }
}
fn update_morphs(
    controls: Option<ResMut<WeightsControl>>,
    mut morphs: Query<&mut MorphWeights>,
    input: Res<ButtonInput<KeyCode>>,
    time: Res<Time>,
) {
    let Some(mut controls) = controls else {
        return;
    };
    for (i, target) in controls.weights.iter_mut().enumerate() {
        if !AVAILABLE_KEYS[i].active(&input) {
            continue;
        }
        let Ok(mut weights) = morphs.get_mut(target.entity) else {
            continue;
        };
        // To update individual morph target weights, get the `MorphWeights`
        // component and call `weights_mut` to get access to the weights.
        let weights_slice = weights.weights_mut();
        let i = target.index;
        let change = time.delta_seconds() * WEIGHT_PER_SECOND;
        let new_weight = target.change_dir.change_weight(weights_slice[i], change);
        weights_slice[i] = new_weight;
        target.weight = new_weight;
    }
}

fn detect_morphs(
    mut commands: Commands,
    morphs: Query<(Entity, &MorphWeights, Option<&Name>)>,
    meshes: Res<Assets<Mesh>>,
    scene_handle: Res<SceneHandle>,
    mut setup: Local<bool>,
    asset_server: Res<AssetServer>,
) {
    let no_morphing = morphs.iter().len() == 0;
    if no_morphing {
        return;
    }
    if scene_handle.is_loaded && !*setup {
        *setup = true;
    } else {
        return;
    }
    let mut detected = Vec::new();

    for (entity, weights, name) in &morphs {
        let target_names = weights
            .first_mesh()
            .and_then(|h| meshes.get(h))
            .and_then(|m| m.morph_target_names());
        let targets = Target::new(name, weights.weights(), target_names, entity);
        detected.extend(targets);
    }
    detected.truncate(AVAILABLE_KEYS.len());
    let style = TextStyle {
        font: asset_server.load("assets/fonts/FiraMono-Medium.ttf"),
        font_size: 13.0,
        ..default()
    };
    let mut sections = vec![
        TextSection::new("Morph Target Controls\n", style.clone()),
        TextSection::new("---------------\n", style.clone()),
    ];
    let target_to_text =
        |(i, target): (usize, &Target)| target.text_section(AVAILABLE_KEYS[i].name, style.clone());
    sections.extend(detected.iter().enumerate().map(target_to_text));
    commands.insert_resource(WeightsControl { weights: detected });
    commands.spawn(TextBundle::from_sections(sections).with_style(Style {
        position_type: PositionType::Absolute,
        top: Val::Px(10.0),
        left: Val::Px(10.0),
        ..default()
    }));
}

pub fn weights_mut(&mut self) -> &mut [f32]

Examples found in repository ?

examples/tools/scene_viewer/morph_viewer_plugin.rs (line 220)

fn update_morphs(
    controls: Option<ResMut<WeightsControl>>,
    mut morphs: Query<&mut MorphWeights>,
    input: Res<ButtonInput<KeyCode>>,
    time: Res<Time>,
) {
    let Some(mut controls) = controls else {
        return;
    };
    for (i, target) in controls.weights.iter_mut().enumerate() {
        if !AVAILABLE_KEYS[i].active(&input) {
            continue;
        }
        let Ok(mut weights) = morphs.get_mut(target.entity) else {
            continue;
        };
        // To update individual morph target weights, get the `MorphWeights`
        // component and call `weights_mut` to get access to the weights.
        let weights_slice = weights.weights_mut();
        let i = target.index;
        let change = time.delta_seconds() * WEIGHT_PER_SECOND;
        let new_weight = target.change_dir.change_weight(weights_slice[i], change);
        weights_slice[i] = new_weight;
        target.weight = new_weight;
    }
}