Struct Transform 

pub struct Transform {
    pub position: Vec3,
    pub rotation: Quat,
    pub scale: Vec3,
    /* private fields */
}

Transform component for scene nodes.

Encapsulates position, rotation, and scale (TRS) along with cached matrices and dirty-checking logic for efficient updates.

Coordinate System

Uses a right-handed coordinate system:

• +X: Right
• +Y: Up
• +Z: Forward (out of screen)

Matrix Updates

The transform maintains two cached matrices:

• local_matrix: Transform relative to parent
• world_matrix: Transform relative to world origin

These are updated lazily when TRS values change, tracked by dirty checking against previous frame values.

Example

let mut transform = Transform::new();
transform.position = Vec3::new(1.0, 2.0, 3.0);
transform.rotation = Quat::from_rotation_y(std::f32::consts::FRAC_PI_2);
transform.scale = Vec3::splat(2.0);

Fields

position: Vec3

Local position relative to parent.

rotation: Quat

Local rotation as quaternion.

scale: Vec3

Local scale factor.

Implementations

impl Transform

pub fn new() -> Transform

Creates a new transform with identity values.

pub fn update_local_matrix(&mut self) -> bool

Checks and updates the local matrix if TRS values changed.

Returns true if the matrix was updated, false otherwise. This method is called by the transform system during hierarchy traversal.

pub fn set_rotation_euler(&mut self, x: f32, y: f32, z: f32)

Sets rotation from Euler angles (XYZ order).

Arguments

• x - Rotation around X axis in radians
• y - Rotation around Y axis in radians
• z - Rotation around Z axis in radians

pub fn rotation_euler(&self) -> Vec3

Returns the rotation as Euler angles (XYZ order) in radians.

pub fn set_rotation_euler_with_order( &mut self, x: f32, y: f32, z: f32, order: EulerRot, )

Sets rotation from Euler angles with a custom rotation order.

pub fn local_matrix(&self) -> &Affine3A

Returns a reference to the cached local matrix.

pub fn world_matrix(&self) -> &Affine3A

Returns a reference to the cached world matrix.

pub fn world_matrix_as_mat4(&self) -> Mat4

Returns the world matrix converted to Mat4.

pub fn set_world_matrix(&mut self, mat: Affine3A)

Sets the world matrix directly.

pub fn set_position(&mut self, pos: Vec3)

Sets position and marks the transform dirty.

pub fn apply_local_matrix(&mut self, mat: Affine3A)

Directly sets the local matrix (e.g. from glTF or a physics engine). Decomposes it into TRS and synchronizes state.

pub fn apply_local_matrix_from_mat4(&mut self, mat: Mat4)

Applies a local matrix from Mat4.

pub fn look_at(&mut self, target: Vec3, up: Vec3)

Orients the transform to face a target point (in parent space).

pub fn mark_dirty(&mut self)

Marks the transform as dirty, forcing a matrix recompute next frame.

pub fn rotation_basis(&self) -> (Vec3, Vec3, Vec3)

Returns the local coordinate axes based on current rotation.

Returns (right, up, forward) vectors in world space.

Trait Implementations

impl Clone for Transform

fn clone(&self) -> Transform

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Transform

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Transform

fn default() -> Transform

Returns the “default value” for a type.

impl Copy for Transform