var horizontalSpeedToEnableEmitters = 1.0;

private var areEmittersOn : boolean;

private var oldPosition : Vector3; private var currentVelocity : Vector3;

function Start() {

oldPosition = transform.position;

}

function Update() {

wereEmittersOn = areEmittersOn;


areEmittersOn = (currentVelocity.y > 0) || (Mathf.Abs(currentVelocity.x) > horizontalSpeedToEnableEmitters);


if (wereEmittersOn != areEmittersOn) {

    for (var emitter in GetComponentsInChildren(ParticleEmitter)) {

       emitter.emit = areEmittersOn;
    }
}