kite3d/io.github.yuroyami.kite3d.math.interpolants/BezierInterpolant

BezierInterpolant

class BezierInterpolant(parameterPositions: DoubleArray, sampleValues: DoubleArray, sampleSize: Int, resultBuffer: DoubleArray = DoubleArray(sampleSize)) : Interpolant

A Bezier interpolant using cubic Bezier curves with 2D control points.

This interpolant supports the COLLADA/Maya style of Bezier animation where each keyframe has explicit in/out tangent control points specified as 2D coordinates (time, value).

The tangent data must be provided via the settings object:

settings.inTangents: packed [time, value] pairs per keyframe per component.
settings.outTangents: packed [time, value] pairs per keyframe per component.

For a track with N keyframes and stride S:

Each tangent array has N * S * 2 values.
Layout: [k0_c0_time, k0_c0_value, k0_c1_time, k0_c1_value, ..., k1_c0_time, k1_c0_value, ...], where k is the keyframe and c the component.

When no tangent data is present, this falls back to linear interpolation.

Parameters

parameterPositions

The parameter positions holding the interpolation factors.

sampleValues

The sample values.

sampleSize

The number of values in one sample (the stride).

resultBuffer

The result buffer; defaults to a fresh DoubleArray(sampleSize).

Constructors

BezierInterpolant

constructor(parameterPositions: DoubleArray, sampleValues: DoubleArray, sampleSize: Int, resultBuffer: DoubleArray = DoubleArray(sampleSize))

Properties

DefaultSettings_

open val DefaultSettings_: InterpolantSettings

The default settings object. Overridden by CubicInterpolant.

parameterPositions

val parameterPositions: DoubleArray

The parameter positions.

val resultBuffer: DoubleArray

The result buffer. Reused across calls; overwritten by every evaluate.

val sampleValues: DoubleArray

The sample values.

var settings: InterpolantSettings?

The interpolation settings. null until assigned; getSettings_ then falls back to DefaultSettings_.

val valueSize: Int

The value size (stride).

Functions

copySampleValue_

open fun copySampleValue_(index: Int): DoubleArray

Copies a sample value to the result buffer.

fun evaluate(t: Double): DoubleArray

Evaluates the interpolant at position t.

fun getSettings_(): InterpolantSettings

Returns the interpolation settings.