THREE.LoopOnce
THREE.LoopRepeat
THREE.LoopPingPong
THREE.InterpolateDiscrete
THREE.InterpolateLinear
THREE.InterpolateSmooth
THREE.ZeroCurvatureEnding
THREE.ZeroSlopeEnding
THREE.WrapAroundEnding
[link:https://github.com/mrdoob/three.js/blob/master/src/constants.js src/constants.js]