Module `blend`

Allocation-free local-pose and blend-space utilities.

Quick Reference

Item	Kind	Description
`BlendSpace1D`	struct	The `BlendSpace1D` struct stores validated scalar sample positions for allocation-free weight evaluation.
`BlendTriangle`	struct	The `BlendTriangle` struct identifies three sample indices forming one non-degenerate 2D blend region.
`BlendSpace2D`	struct	The `BlendSpace2D` struct stores validated points and triangles for allocation-free directional blending.
`BlendError`	enum	Errors returned when local poses cannot be blended.
`BlendSpaceError`	enum	Errors returned when constructing or evaluating a blend space.
`blend_local_transform`	fn	Blends two local transforms while preserving the shortest quaternion path.
`blend_local_pose`	fn	Blends two complete local poses into caller-owned storage.
`blend_local_poses`	fn	Blends any number of complete local poses with normalized non-negative weights.

Structs

`BlendSpace1D`

struct BlendSpace1D {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/animation/blend.rs:92-94

The BlendSpace1D struct stores validated scalar sample positions for allocation-free weight evaluation.

Implementations

```
fn new(positions: impl Into<Vec<f32>>) -> Result<Self, BlendSpaceError>
```
Related: BlendSpaceError

Creates a blend space with finite, strictly ascending sample positions.

Next, call Self::write_weights during evaluation and pass the weights

to blend_local_poses.
```
fn len(&self) -> usize
```
Returns the number of samples and weights required by Self::write_weights.
```
fn is_empty(&self) -> bool
```
Returns whether the blend space contains no samples.
```
fn write_weights(&self, value: f32, output: &mut [f32]) -> Result<(), BlendSpaceError>
```
Related: BlendSpaceError

Writes normalized weights for a scalar parameter, clamping outside the sample range.

Trait Implementations

`impl ArchivePointee for BlendSpace1D`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for BlendSpace1D`

`impl Clone for BlendSpace1D`

```
fn clone(&self) -> BlendSpace1D
```
Related: BlendSpace1D

`impl Debug for BlendSpace1D`

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

`impl Downcast for BlendSpace1D`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for BlendSpace1D`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for BlendSpace1D`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Instrument for BlendSpace1D`

`impl LayoutRaw for BlendSpace1D`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for BlendSpace1D`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for BlendSpace1D`

fn eq(&self, other: &BlendSpace1D) -> bool

Related: BlendSpace1D

`impl Pointable for BlendSpace1D`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for BlendSpace1D`

```
type Metadata = ()
```

`impl Read for BlendSpace1D`

`impl StructuralPartialEq for BlendSpace1D`

`impl WithSubscriber for BlendSpace1D`

`BlendTriangle`

struct BlendTriangle([usize; 3]);

Defined in crates/byte-engine/src/animation/blend.rs:154-157

The BlendTriangle struct identifies three sample indices forming one non-degenerate 2D blend region.

Trait Implementations

`impl ArchivePointee for BlendTriangle`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for BlendTriangle`

`impl Clone for BlendTriangle`

```
fn clone(&self) -> BlendTriangle
```
Related: BlendTriangle

`impl Copy for BlendTriangle`

`impl Debug for BlendTriangle`

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

`impl Downcast for BlendTriangle`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for BlendTriangle`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for BlendTriangle`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for BlendTriangle`

`impl<K> Equivalent for BlendTriangle`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Instrument for BlendTriangle`

`impl LayoutRaw for BlendTriangle`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for BlendTriangle`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for BlendTriangle`

fn eq(&self, other: &BlendTriangle) -> bool

Related: BlendTriangle

`impl Pointable for BlendTriangle`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for BlendTriangle`

```
type Metadata = ()
```

`impl Read for BlendTriangle`

`impl StructuralPartialEq for BlendTriangle`

`impl WithSubscriber for BlendTriangle`

`BlendSpace2D`

struct BlendSpace2D {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/animation/blend.rs:161-164

The BlendSpace2D struct stores validated points and triangles for allocation-free directional blending.

Implementations

```
fn new(positions: impl Into<Vec<[f32; 2]>>, triangles: impl Into<Vec<BlendTriangle>>) -> Result<Self, BlendSpaceError>
```
Related: BlendTriangle, BlendSpaceError

Creates a triangulated blend space.

Triangles may share edges but must not be degenerate. Next, call

Self::write_weights to find the containing triangle or the closest

point on the triangulated boundary.
```
fn len(&self) -> usize
```
Returns the number of samples and weights required by Self::write_weights.
```
fn is_empty(&self) -> bool
```
Returns whether the blend space contains no samples.
```
fn write_weights(&self, value: [f32; 2], output: &mut [f32]) -> Result<(), BlendSpaceError>
```
Related: BlendSpaceError

Writes normalized weights for a 2D parameter without allocating.

Values outside the triangulated region clamp to the closest point on any

triangle, which provides stable behavior at directional blend-space edges.

Trait Implementations

`impl ArchivePointee for BlendSpace2D`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for BlendSpace2D`

`impl Clone for BlendSpace2D`

```
fn clone(&self) -> BlendSpace2D
```
Related: BlendSpace2D

`impl Debug for BlendSpace2D`

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

`impl Downcast for BlendSpace2D`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for BlendSpace2D`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for BlendSpace2D`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Instrument for BlendSpace2D`

`impl LayoutRaw for BlendSpace2D`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for BlendSpace2D`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for BlendSpace2D`

fn eq(&self, other: &BlendSpace2D) -> bool

Related: BlendSpace2D

`impl Pointable for BlendSpace2D`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for BlendSpace2D`

```
type Metadata = ()
```

`impl Read for BlendSpace2D`

`impl StructuralPartialEq for BlendSpace2D`

`impl WithSubscriber for BlendSpace2D`

Enums

`BlendError`

enum BlendError {
    InputCount {
        poses: usize,
        weights: usize,
    },
    PoseLength {
        expected: usize,
        actual: usize,
    },
    InvalidWeight,
    ZeroWeight,
}

Defined in crates/byte-engine/src/animation/blend.rs:260-279

Errors returned when local poses cannot be blended.

Variants

InputCount

The pose and weight counts differ, or no poses were supplied.
PoseLength

An input pose does not match the output node count.
InvalidWeight

A weight is negative or non-finite.
ZeroWeight

All supplied weights are zero.

Trait Implementations

`impl ArchivePointee for BlendError`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for BlendError`

`impl Clone for BlendError`

```
fn clone(&self) -> BlendError
```
Related: BlendError

`impl Copy for BlendError`

`impl Debug for BlendError`

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

`impl Display for BlendError`

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

`impl Downcast for BlendError`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for BlendError`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for BlendError`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for BlendError`

`impl<K> Equivalent for BlendError`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Error for BlendError`

`impl Instrument for BlendError`

`impl LayoutRaw for BlendError`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for BlendError`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for BlendError`

fn eq(&self, other: &BlendError) -> bool

Related: BlendError

`impl Pointable for BlendError`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for BlendError`

```
type Metadata = ()
```

`impl Read for BlendError`

`impl StructuralPartialEq for BlendError`

`impl ToString for BlendError`

```
fn to_string(&self) -> String
```

`impl WithSubscriber for BlendError`

`BlendSpaceError`

enum BlendSpaceError {
    NotEnoughSamples {
        minimum: usize,
    },
    NonFiniteSample,
    SamplesNotStrictlyAscending,
    NoTriangles,
    TriangleSampleOutOfRange {
        triangle: usize,
    },
    DegenerateTriangle {
        triangle: usize,
    },
    OutputLength {
        expected: usize,
        actual: usize,
    },
    NonFiniteParameter,
}

Defined in crates/byte-engine/src/animation/blend.rs:308-339

Errors returned when constructing or evaluating a blend space.

Variants

NotEnoughSamples

The blend space has fewer samples than its topology requires.
NonFiniteSample

A sample position contains a non-finite component.
SamplesNotStrictlyAscending

One-dimensional sample positions are unsorted or duplicated.
NoTriangles

A two-dimensional blend space has no triangles.
TriangleSampleOutOfRange

A triangle references a sample outside the position list.
DegenerateTriangle

A triangle uses repeated or collinear sample positions.
OutputLength

The output slice cannot hold one weight per sample.
NonFiniteParameter

The evaluation parameter contains a non-finite component.

Trait Implementations

`impl ArchivePointee for BlendSpaceError`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for BlendSpaceError`

`impl Clone for BlendSpaceError`

```
fn clone(&self) -> BlendSpaceError
```
Related: BlendSpaceError

`impl Copy for BlendSpaceError`

`impl Debug for BlendSpaceError`

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

`impl Display for BlendSpaceError`

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

`impl Downcast for BlendSpaceError`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for BlendSpaceError`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for BlendSpaceError`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for BlendSpaceError`

`impl<K> Equivalent for BlendSpaceError`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Error for BlendSpaceError`

`impl Instrument for BlendSpaceError`

`impl LayoutRaw for BlendSpaceError`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for BlendSpaceError`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for BlendSpaceError`

fn eq(&self, other: &BlendSpaceError) -> bool

Related: BlendSpaceError

`impl Pointable for BlendSpaceError`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for BlendSpaceError`

```
type Metadata = ()
```

`impl Read for BlendSpaceError`

`impl StructuralPartialEq for BlendSpaceError`

`impl ToString for BlendSpaceError`

```
fn to_string(&self) -> String
```

`impl WithSubscriber for BlendSpaceError`

Functions

`blend_local_transform`

fn blend_local_transform(left: resource_management::resources::skeleton::LocalTransform, right: resource_management::resources::skeleton::LocalTransform, factor: f32) -> resource_management::resources::skeleton::LocalTransform

Defined in crates/byte-engine/src/animation/blend.rs:8-15

Blends two local transforms while preserving the shortest quaternion path.

`blend_local_pose`

fn blend_local_pose(left: &[resource_management::resources::skeleton::LocalTransform], right: &[resource_management::resources::skeleton::LocalTransform], factor: f32, output: &mut [resource_management::resources::skeleton::LocalTransform]) -> Result<(), BlendError>

Defined in crates/byte-engine/src/animation/blend.rs:18-29

Blends two complete local poses into caller-owned storage.

`blend_local_poses`

fn blend_local_poses(poses: &[&[resource_management::resources::skeleton::LocalTransform]], weights: &[f32], output: &mut [resource_management::resources::skeleton::LocalTransform]) -> Result<(), BlendError>

Defined in crates/byte-engine/src/animation/blend.rs:35-88

Blends any number of complete local poses with normalized non-negative weights.

Quaternion components use the first positively weighted pose as their hemisphere reference. This keeps antipodal representations from cancelling.

blend

On this page