API Reference > geometry-core > CartesianGeometry > Point2dArrayCarrier > crossProductIndexIndexIndex crossProductIndexIndexIndex Method Return the cross product of vectors from point at originIndex to points at indexA and indexB crossProductIndexIndexIndex(originIndex: number, indexA: number, indexB: number): number | undefined Parameter Type Description originIndex number index of origin indexA number index of first target within the array indexB number index of second target within the array Returns - number | undefined return true if indexA, indexB both valid Defined in core/geometry/src/geometry3d/Point2dArrayCarrier.ts Line 105 Last Updated: 15 June, 2021