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

public class Spline : object, ISpline, IReadOnlyList<BezierKnot>, IList<BezierKnot>

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

Count

Return the number of knots.

Declaration

public int Count { get; }

Property Value

Type	Description
Int32

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.

IsReadOnly

Returns true if this Spline is read-only, false if it is mutable.

Declaration

public bool IsReadOnly { get; }

Property Value

Type	Description
Boolean

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

Knots

A collection of BezierKnot.

Declaration

public IEnumerable<BezierKnot> Knots { get; }

Property Value

Type	Description
IEnumerable<BezierKnot>

Methods

Add(BezierKnot)

Adds a knot to the spline.

Declaration

public void Add(BezierKnot item)

Parameters

Type	Name	Description
BezierKnot	item	The BezierKnot to add.

Clear()

Remove all knots from the spline.

Declaration

public void Clear()

Contains(BezierKnot)

Return true if a knot is present in the spline.

Declaration

public bool Contains(BezierKnot item)

Parameters

Type	Name	Description
BezierKnot	item	The BezierKnot to locate.

Returns

Type	Description
Boolean	Returns true if the knot is found, false if it is not present.

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.

CopyTo(BezierKnot[], Int32)

Copies the contents of the knot list to an array starting at an index.

Declaration

public void CopyTo(BezierKnot[] array, int arrayIndex)

Parameters

Type	Name	Description
BezierKnot[]	array	The destination array to place the copied item in.
Int32	arrayIndex	The zero-based index to copy.

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)

GetCurveInterpolation(Int32, Single)

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

Declaration

public float GetCurveInterpolation(int curveIndex, float curveDistance)

Parameters

Type	Name	Description
Int32	curveIndex	The zero-based index of the curve.
Single	curveDistance	The curve-relative distance to convert to an interpolation ratio (also referred to as 't').

Returns

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

Implements

ISpline.GetCurveInterpolation(Int32, Single)

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()

GetEnumerator()

Get an enumerator that iterates through the BezierKnot collection.

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, accounting for Closed state. Note that this value is not accounting for transform hierarchy. If you require length in world space use CalculateLength<T>(T, 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)

IndexOf(BezierKnot)

Return the first index of an element matching item.

Declaration

public int IndexOf(BezierKnot item)

Parameters

Type	Name	Description
BezierKnot	item	The knot to locate.

Returns

Type	Description
Int32	The zero-based index of the knot, or -1 if not found.

Insert(Int32, BezierKnot)

Insert a BezierKnot at the specified index.

Declaration

public void Insert(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.

Remove(BezierKnot)

Removes the first matching knot.

Declaration

public bool Remove(BezierKnot item)

Parameters

Type	Name	Description
BezierKnot	item	The BezierKnot to locate and remove.

Returns

Type	Description
Boolean	Returns true if a matching item was found and removed, false if no match was discovered.

RemoveAt(Int32)

Removes the knot at the specified index.

Declaration

public void RemoveAt(int index)

Parameters

Type	Name	Description
Int32	index	The zero-based index of the element to remove.

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.

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 in the editor 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.