patternTest

using UnityEngine;
using System.Collections.Generic;
using Leap;

public class patternTest_2 : MonoBehaviour {

	#region [Leap motion parameters]
	HandModel 	handModel;
	Hand 		leapHand;
	FingerModel indexFingerModel;
	#endregion
	
	#region [Public Parameters]
	public int   	positionCacheNum = 180;    // 格納する最小点数（60 fps なら 180 で 3 sec 分保存）
	public Vector3 	indexTip;
	public Vector3 	thumbTip;
	#endregion

	#region [Velocity Parameters]
	public float velocity;	//velocity of the finger
	Vector3 currPosition;	//finger's current frame position
	Vector3 prePosition;	//finger's previous frame position
	#endregion
	
	#region [Private Parameters]
	private List<Vector3> 	positions_    			= new List<Vector3>();	//recording parameter
	private const float 	THUMB_TRIGGER_DISTANCE 	= 0.04f;				//Minimum distance to trigger the test
	private const float 	MIN_CONFIDENCE 			= 0.2f;					//Minimum value of handmodel confidence
	#endregion
	
	// Update is called once per frame
	void Update () {
		//define LeapHands & Fingers
		handModel = GetComponent<HandModel> ();
		leapHand = handModel.GetLeapHand ();
		//get indexfinger
		indexFingerModel = handModel.fingers [1];
		//get indexfingerTip position
		indexTip = indexFingerModel.GetTipPosition ();	
		//get thumbTip position
		thumbTip = leapHand.Fingers [0].TipPosition.ToUnityScaled ();

		//calculating velocity of finger
		currPosition = thumbTip;
		velocity = (currPosition - prePosition).magnitude / Time.deltaTime;
		prePosition = thumbTip;
	
		//Trigger test (true: thumbTip got close to rest of fingers)
		bool patternTrigger = false;
		for (int i = 1; i<5 && !patternTrigger; ++i) {
			for(int j = 0; j<4 && !patternTrigger; ++j){
				Finger.FingerJoint joint = (Finger.FingerJoint)(j);
				Vector3 difference = leapHand.Fingers[i].JointPosition(joint).ToUnityScaled() - thumbTip;
				if(difference.magnitude < THUMB_TRIGGER_DISTANCE 
				   && leapHand.Confidence > MIN_CONFIDENCE){
					//Trigger is ON
					patternTrigger = true;
				}
			}
		}
		//Particle system On/Off
		switch (patternTrigger) {
		case(true):	
			//Start recording finger position
			AddPositionCache (indexTip);
			transform.FindChild("particle").gameObject.SetActive(true);
			break;
		case(false):
			transform.FindChild("particle").gameObject.SetActive(false);
			break;
		}

		if (DetectFingerGesture ()) {

			//Detected!
		}

	}

	//Add finger position
	void AddPositionCache(Vector3 position)
	{
		positions_.Insert(0, position);
		if (positions_.Count > positionCacheNum) {
			positions_.RemoveAt(positions_.Count - 1);
		}
	}

	//Detecting finger Gesture (Up||Down)
	bool DetectFingerGesture ()
	{
		var positionSum = Vector3.zero;

		for (int i = 0; i<positions_.Count; i++) {
			positionSum += positions_ [i];
			//Distance between First and Last Point
			float disBtwFirstLast = Vector3.Distance (positions_ [i], positions_ [0]);
			//X-coordinate distance change of the finger
			float xPositionCheck = Mathf.Abs (positions_ [i].x - positions_ [0].x);
			//Y-coordinate distance change of the finger
			float yPositionCheck = (positions_ [i].y - positions_ [0].y);

			//Gesture trigger checking point
			if (disBtwFirstLast > 3.0f && xPositionCheck < 0.05f && velocity>0.8f) {

				if (yPositionCheck > 0) {
					//Downward Motion
					Debug.Log ("Down Motion PASS");
					Reset ();
				}else if (yPositionCheck < 0) {
					//Upward Motion
					Debug.Log ("Up Motion PASS");
					Reset ();
				}
				return true;

			}
		}
		return false;
	}

	//Reseting position records
	void Reset ()
	{
		positions_.Clear();
	}
}

pointerFollow

using UnityEngine;
using System.Collections;
using Leap;


public class mouseFollow : MonoBehaviour {

	void Start(){
		gameObject.SetActive (false);
	}

	// Update is called once per frame
	void Update () {
			transform.position = GetComponentInParent<patternTest> ().indexTip;
			transform.position = GetComponentInParent<patternTest_2> ().indexTip;

	}
}

Youtube video: https://youtu.be/9jlVvRYOMvo