API Reference > geometry-core > Serialization > IModelJson > IModelJson.TransitionSpiralProps > activeFractionInterval activeFractionInterval activeFractionInterval: undefined | number[] Fractional part of active interval. There has been name confusion between native and typescript .... accept any variant .. native (July 2020) emits activeFractionInterval Defined in serialization/IModelJsonSchema.ts Line 342 Last Updated: 11 June, 2024