EasingCurve: CurveBase & {
    curveFunction: CurveFunction;
    type: LifeTimeCurve.EASING;
}

An easing curve representation using a custom function.

{
* type: LifeTimeCurve.EASING,
* curveFunction: (time) => Math.sin(time * Math.PI) // Simple easing function
* }