API Reference > geometry-core > CartesianGeometry > Ellipsoid > radiansToUnitNormalRay radiansToUnitNormalRay Method Evaluate a point and unit normal at given angles. radiansToUnitNormalRay(thetaRadians: number, phiRadians: number, result?: Ray3d): Ray3d | undefined Parameter Type Description thetaRadians number longitude, in radians phiRadians number latitude, in radians result Ray3d optional transform result Returns - Ray3d | undefined Defined in core/geometry/src/geometry3d/Ellipsoid.ts Line 629 Last Updated: 13 June, 2024