Class Spline

The Spline class is a collection of BezierKnot, the closed/open state, and editing representation.

Inheritance

Object

Spline

RollercoasterTrack

Namespace: UnityEngine.Splines

Syntax

[Serializable]
public class Spline : ISpline

Constructors

Spline()

Default constructor creates a spline with no knots, not closed.

Declaration

public Spline()

Spline(IEnumerable<BezierKnot>, Boolean)

Create a spline from a collection of BezierKnot.

Declaration

public Spline(IEnumerable<BezierKnot> knots, bool closed = false)

Parameters

Type	Name	Description
IEnumerable<BezierKnot>	knots	A collection of BezierKnot.
Boolean	closed	Whether the spline is open (has a start and end point) or closed (forms an unbroken loop).

Spline(Int32, Boolean)

Create a spline with a pre-allocated knot capacity.

Declaration

public Spline(int knotCapacity, bool closed = false)

Parameters

Type	Name	Description
Int32	knotCapacity	The capacity of the knot collection.
Boolean	closed	Whether the spline is open (has a start and end point) or closed (forms an unbroken loop).

Properties

Closed

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

Declaration

public bool Closed { get; set; }

Property Value

Type	Description
Boolean

Implements

ISpline.Closed

EditType

The SplineType that this spline should be presented as to the user.

Declaration

public SplineType EditType { get; set; }

Property Value

Type	Description
SplineType

Remarks

Internally all splines are stored as a collection of bezier knots, and when editing converted or displayed with the handles appropriate to the editable type.

Item[Int32]

Get or set the knot at index.

Declaration

public BezierKnot this[int index] { get; set; }

Parameters

Type	Name	Description
Int32	index	The zero-based index of the element to get or set.

Property Value

Type	Description
BezierKnot

Implements

ISpline.Item[Int32]

KnotCount

Return the number of knots.

Declaration

public int KnotCount { get; }

Property Value

Type	Description
Int32

Implements

ISpline.KnotCount

Knots

A collection of BezierKnot.

Declaration

public IEnumerable<BezierKnot> Knots { get; }

Property Value

Type	Description
IEnumerable<BezierKnot>

Methods

AddKnot(BezierKnot)

Append a knot to the end of the knot list.

Declaration

public void AddKnot(BezierKnot knot)

Parameters

Type	Name	Description
BezierKnot	knot	The element to append.

Copy(Spline)

Copy the values from toCopy to this spline.

Declaration

public void Copy(Spline toCopy)

Parameters

Type	Name	Description
Spline	toCopy	The Spline to copy property data from.

GetCurve(Int32)

Get a BezierCurve from a knot index.

Declaration

public BezierCurve GetCurve(int index)

Parameters

Type	Name	Description
Int32	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.

Implements

ISpline.GetCurve(Int32)

GetCurveLength(Int32)

Return the length of a curve.

Declaration

public float GetCurveLength(int index)

Parameters

Type	Name	Description
Int32	index

Returns

Type	Description
Single

Implements

ISpline.GetCurveLength(Int32)

See Also

Warmup()

GetLength()

GetLength()

Return the sum of all curve lengths, accounting for Closed state. Note that this value is not accounting for transform hierarchy. If you require length in world space use CalculateLength(Spline, float4x4).

Declaration

public float GetLength()

Returns

Type	Description
Single	Returns the sum length of all curves composing this spline, accounting for closed state.

Implements

ISpline.GetLength()

Remarks

This value is cached. It is recommended to call this once in a non-performance critical path to ensure that the cache is valid.

See Also

Warmup()

GetCurveLength(Int32)

InsertKnot(Int32, BezierKnot)

Insert a BezierKnot at the specified index.

Declaration

public void InsertKnot(int index, BezierKnot knot)

Parameters

Type	Name	Description
Int32	index	The zero-based index to insert the new element.
BezierKnot	knot	The BezierKnot to insert.

OnSplineChanged()

Invoked any time a spline property is modified.

Declaration

protected virtual void OnSplineChanged()

Remarks

In the editor this can be invoked many times per-frame. Prefer to use afterSplineWasModified when working with splines in the editor.

Resize(Int32)

Change the size of the BezierKnot list.

Declaration

public void Resize(int newSize)

Parameters

Type	Name	Description
Int32	newSize	The new size of the knots collection.

ToArray()

Create an array of spline knots.

Declaration

public BezierKnot[] ToArray()

Returns

Type	Description
BezierKnot[]	Return a new array copy of the knots collection.

ToNativeArray(Allocator)

Create a new native array of spline knots.

Declaration

public NativeArray<BezierKnot> ToNativeArray(Allocator allocator)

Parameters

Type	Name	Description
Allocator	allocator	The allocator to construct the NativeArray with.

Returns

Type	Description
NativeArray<BezierKnot>	Return a new array copy of the knots collection.

ToNativeSpline(Allocator)

Create a new NativeSpline copy of this spline. A NativeSpline contains a NativeArray of BezierKnot, and the closed state of a spline.

Declaration

public NativeSpline ToNativeSpline(Allocator allocator = Allocator.Temp)

Parameters

Type	Name	Description
Allocator	allocator	The allocator to be passed when constructing the knots NativeArray.

Returns

Type	Description
NativeSpline	A new NativeSpline representation of this Spline.

ToNativeSpline(float4x4, Allocator)

Create a new NativeSpline copy of this spline. A NativeSpline contains a NativeArray of BezierKnot, and the closed state of a spline.

Declaration

public NativeSpline ToNativeSpline(float4x4 transform, Allocator allocator = Allocator.Temp)

Parameters

Type	Name	Description
float4x4	transform	Transformation matrix to be applied to knots.
Allocator	allocator	The allocator to be passed when constructing the knots NativeArray.

Returns

Type	Description
NativeSpline	A new NativeSpline representation of this Spline.

Warmup()

Ensure that all caches contain valid data. Call this to avoid unexpected performance costs when accessing spline data. Caches remain valid until any part of the spline state is modified.

Declaration

public void Warmup()

Events

changed

Invoked any time a spline property is modified.

Declaration

public event Action changed

Event Type

Type	Description
Action

Remarks

In the editor this can be invoked many times per-frame. Prefer to use when working with splines in the editor.

Extension Methods

SplineUtility.EvaluatePosition<T>(T, Single)

SplineUtility.EvaluateDirection<T>(T, Single)

SplineUtility.EvaluateUpVector<T>(T, Single)

SplineUtility.SplineToCurveInterpolation<T>(T, Single, out Single)