Struct BoneTransformComputer 

pub struct BoneTransformComputer { /* private fields */ }

Bone transform computer for hierarchical bone matrices

Handles the transformation chain from local bone space to model space, accounting for parent bones, pivot points, and billboard modes.

Implementations

impl BoneTransformComputer

pub fn new(pivot_points: &[Vec3], parents: &[i16], raw_flags: &[u32]) -> Self

Create a new bone transform computer

Arguments

• pivots - Pivot points for each bone
• parents - Parent bone index for each bone (-1 for root)
• flags - Bone flags for each bone

pub fn empty() -> Self

Create an empty computer (no bones)

pub fn bone_count(&self) -> usize

Get number of bones

pub fn update( &mut self, translations: &[Vec3], rotations: &[Quat], scales: &[Vec3], )

Update all bone transforms from interpolated animation values

Arguments

• translations - Interpolated translation for each bone
• rotations - Interpolated rotation for each bone
• scales - Interpolated scale for each bone

pub fn bones(&self) -> &[ComputedBone]

Get computed bone data

pub fn get_transform(&self, bone_index: usize) -> Mat4

Get transform for a specific bone

pub fn get_post_billboard_transform(&self, bone_index: usize) -> Mat4

Get post-billboard transform for a specific bone

pub fn get_skinning_transform(&self, bone_index: usize) -> Mat4

Get combined transform for skinning (uses post_billboard for most bones)

For regular bones, this returns post_billboard_transform. For billboard bones, the shader combines transform and post_billboard with the camera rotation.

pub fn is_spherical_billboard(&self, bone_index: usize) -> bool

Check if a bone uses spherical billboard

pub fn get_gpu_data(&self) -> Vec<f32>

Get all bone matrices as flat array for GPU upload

Each bone contributes 2 mat4x3 matrices (24 floats):

• transform (for billboard positioning)
• post_billboard_transform (for final skinning)