API Reference > geometry-core > Curve > DirectSpiral3d > createAustralianRail createAustralianRail MethodStatic Create an AustralianRailCorp spiral This is y= m*x^3 with x any point on the x axis fraction along the spiral goes to x = fraction * L m is gamma / (6RL) 1/(6RL) is the leading term of the sine series. gamma = 2R/sqrt (4RR-LL) pushes y up a little bit to simulate the lost series terms. createAustralianRail(localToWorld: Transform, nominalL1: number, nominalR1: number, activeInterval?: Segment1d): undefined | DirectSpiral3d Parameter Type Description localToWorld Transform nominalL1 number nominalR1 number activeInterval Segment1d Returns - undefined | DirectSpiral3d Defined in curve/spiral/DirectSpiral3d.ts Line 311 Last Updated: 11 June, 2024