Struct SplineSlice<T>

SplineSlice represents a partial or complete range of curves from another Spline. A SplineSlice<T> by itself does not store any BezierKnots. It stores a reference to a separate Spline, then retrieves knots by iterating the SplineRange. Use SplineSlice<T> in conjunction with SplinePath to create seamless paths from discrete Spline segments.

This class is a data structure that defines the range of curves to associate together. This class is not meant to be used intensively for runtime evaluation because it is not performant. Data is not meant to be stored in that struct and that struct is not reactive to spline changes. The GameObject that contains this slice can be scaled and the knots of the targeted spline that can moved around the curve length cannot be stored here so evaluating positions, tangents and up vectors is expensive.

If performance is a critical requirement, create a new Spline or NativeSpline from the relevant SplinePath<T> or SplineSlice<T>. Note that you might pass a SplineSlice<T> to constructors for both Spline and NativeSpline.

Implements

ISpline

IReadOnlyList<BezierKnot>

IReadOnlyCollection<BezierKnot>

IEnumerable<BezierKnot>

IEnumerable

Inherited Members

ValueType.Equals(object)

ValueType.GetHashCode()

ValueType.ToString()

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: UnityEngine.Splines

Assembly: Unity.Splines.dll

Syntax

public struct SplineSlice<T> : ISpline, IReadOnlyList<BezierKnot>, IReadOnlyCollection<BezierKnot>, IEnumerable<BezierKnot>, IEnumerable where T : ISpline

Type Parameters

Name	Description
T	The type of spline that this slice represents.

Remarks

Iterating a SplineSlice<T> is not as efficient as iterating a Spline or NativeSpline because it does not cache any information. Where performance is a concern, create a new Spline or NativeSpline from the SplineSlice<T>.

Constructors

SplineSlice(T, SplineRange)

Constructor for a new SplineSlice.

Declaration

public SplineSlice(T spline, SplineRange range)

Parameters

Type	Name	Description
T	spline	The Spline that this Slice will read BezierKnot and BezierCurve data from.
SplineRange	range	The start index and count of knot indices that compose this slice.

SplineSlice(T, SplineRange, float4x4)

Constructor for a new SplineSlice.

Declaration

public SplineSlice(T spline, SplineRange range, float4x4 transform)

Parameters

Type	Name	Description
T	spline	The Spline that this Slice will read BezierKnot and BezierCurve data from.
SplineRange	range	The start index and count of knot indices that compose this slice.
float4x4	transform	A transform matrix to be applied to the spline knots and tangents.

Fields

Range

An inclusive start index, number of indices, and direction to iterate.

Declaration

public SplineRange Range

Field Value

Type	Description
SplineRange

Spline

The Spline that this Slice will read BezierKnot and BezierCurve data from. A SplineSlice<T> by itself does not store any BezierKnots. Instead, it references a partial or complete range of existing Splines.

Declaration

public T Spline

Field Value

Type	Description
T

Transform

A transform matrix to be applied to the spline knots and tangents.

Declaration

public float4x4 Transform

Field Value

Type	Description
float4x4

Properties

Closed

Whether the spline is open (has a start and end point) or closed (forms an unbroken loop).

Declaration

public bool Closed { get; }

Property Value

Type	Description
bool

Count

Return the number of knots in this branch. This function clamps the Range to the Count of the the referenced Spline.

Declaration

public int Count { get; }

Property Value

Type	Description
int

this[int]

Get a BezierKnot at the zero-based index of this SplineSlice<T>.

Declaration

public BezierKnot this[int index] { get; }

Parameters

Type	Name	Description
int	index	The index to get.

Property Value

Type	Description
BezierKnot

Methods

GetCurve(int)

Get a BezierCurve from a knot index.

Declaration

public BezierCurve GetCurve(int index)

Parameters

Type	Name	Description
int	index	The knot index that serves as the first control point for this curve.

Returns

Type	Description
BezierCurve	A BezierCurve formed by the knot at index and the next knot.

GetCurveInterpolation(int, float)

Return the normalized interpolation (t) corresponding to a distance on a BezierCurve.

Declaration

public float GetCurveInterpolation(int curveIndex, float curveDistance)

Parameters

Type	Name	Description
int	curveIndex	The zero-based index of the curve.
float	curveDistance	The curve-relative distance to convert to an interpolation ratio (also referred to as 't').

Returns

Type	Description
float	The normalized interpolation ratio associated to distance on the designated curve.

Remarks

It is inefficient to call this method frequently, as it will calculate the interpolation lookup table every time it is invoked. In cases where performance is critical, create a new Spline or NativeSpline instead. Note that you may pass a SplineSlice<T> to constructors for both Spline and NativeSpline.

GetCurveLength(int)

Return the length of a curve.

Declaration

public float GetCurveLength(int index)

Parameters

Type	Name	Description
int	index	The index of the curve for which the length needs to be retrieved.

Returns

Type	Description
float	Returns the length of the curve of index 'index' in the spline.

Remarks

The curve length cannot be cached here because the transform matrix associated to this slice might impact that value, like using a non-uniform scale on the GameObject associated with that slice. It is inefficient to call this method frequently, because it calculates the length of the curve every time it is invoked. If performance is a critical requirement, create a new Spline or NativeSpline from the relevant SplinePath<T> or SplineSlice<T>. Note that you might pass a SplineSlice<T> to constructors for both Spline and NativeSpline.

GetCurveUpVector(int, float)

Return the up vector for a t ratio on the curve.

Declaration

public float3 GetCurveUpVector(int index, float t)

Parameters

Type	Name	Description
int	index	The index of the curve for which the length needs to be retrieved.
float	t	A value between 0 and 1 representing the ratio along the curve.

Returns

Type	Description
float3	Returns the up vector at the t ratio of the curve of index 'index'.

Remarks

It is inefficient to call this method frequently, as it will calculate the up Vector of the curve every time it is invoked. In cases where performance is critical, create a new Spline or NativeSpline instead. Note that you may pass a SplineSlice<T> to constructors for both Spline and NativeSpline.

GetEnumerator()

Get an enumerator that iterates through the BezierKnot collection. Note that this will either increment or decrement indices depending on the value of the Direction.

Declaration

public IEnumerator<BezierKnot> GetEnumerator()

Returns

Type	Description
IEnumerator<BezierKnot>	An IEnumerator that is used to iterate the BezierKnot collection.

GetLength()

Return the sum of all curve lengths.

Declaration

public float GetLength()

Returns

Type	Description
float	Returns the sum length of all curves composing this spline.

Remarks

It is inefficient to call this method frequently, as it will calculate the length of all curves every time it is invoked. In cases where performance is critical, create a new Spline or NativeSpline instead. Note that you may pass a SplineSlice<T> to constructors for both Spline and NativeSpline.