Hololens入门之手势识别(使用Manipulation gesture控制物体平移)

Hololens入门之手势识别(使用Manipulation gesture控制物体平移)

本例在
Hololens入门之手势识别(手检测反馈) 的基础上进行修改

Manipulation gesture：保持点击手势，在3D世界中绝对运动

当你想要全息图像1：1响应用户手部移动时，操纵手势能被用于移动、缩放或旋转全息图像。如此的一个用处是使得用户可以在世界中绘制图像或作画。使用所有的手势时，操纵手势的初始目标应该通过凝视来选中。一旦点击手势开始，通过手部移动的任何对对象的操作都能够被处理，在用户操作全息图像时，从而使得用户得以自由地四处张望。

1、修改HandsManager.cs，添加InteractionManager.SourcePressed，InteractionManager.SourceReleased处理函数，用于识别物体被点击和被释放的事件

HandsManager.cs完整代码如下：

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See LICENSE in the project root for license information.

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.VR.WSA.Input;

namespace HoloToolkit.Unity
{
/// <summary>
/// HandsManager determines if the hand is currently detected or not.
/// </summary>
public partial class HandsManager : Singleton<HandsManager>
{
/// <summary>
/// HandDetected tracks the hand detected state.
/// Returns true if the list of tracked hands is not empty.
/// </summary>
public bool HandDetected
{
get { return trackedHands.Count > 0; }
}

private HashSet<uint> trackedHands = new HashSet<uint>();

public GameObject FocusedGameObject { get; private set; }

void Awake()
{
//识别到来源
InteractionManager.SourceDetected += InteractionManager_SourceDetected;
//来源丢失
InteractionManager.SourceLost += InteractionManager_SourceLost;
//来源被按下
InteractionManager.SourcePressed += InteractionManager_SourcePressed;
//被释放
InteractionManager.SourceReleased += InteractionManager_SourceReleased;
FocusedGameObject = null;
}

private void InteractionManager_SourceDetected(InteractionSourceState state)
{
// Check to see that the source is a hand.
if (state.source.kind != InteractionSourceKind.Hand)
{
return;
}

trackedHands.Add(state.source.id);
}

private void InteractionManager_SourceLost(InteractionSourceState state)
{
// Check to see that the source is a hand.
if (state.source.kind != InteractionSourceKind.Hand)
{
return;
}

if (trackedHands.Contains(state.source.id))
{
trackedHands.Remove(state.source.id);
}
FocusedGameObject = null;
}

//手势释放时，将被关注的物体置空
private void InteractionManager_SourceReleased(InteractionSourceState state)
{
FocusedGameObject = null;
}

//识别到手指按下时，将凝视射线关注的物体置为当前手势操作的对象
private void InteractionManager_SourcePressed(InteractionSourceState state)
{
if (GazeManager.Instance.FocusedObject != null)
{
FocusedGameObject = GazeManager.Instance.FocusedObject;
}
}

void OnDestroy()
{
InteractionManager.SourceDetected -= InteractionManager_SourceDetected;
InteractionManager.SourceLost -= InteractionManager_SourceLost;
InteractionManager.SourceReleased -= InteractionManager_SourceReleased;
InteractionManager.SourcePressed -= InteractionManager_SourcePressed;
}
}
}

2、修改GestureManager.cs，订阅Manipulation gesture事件

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See LICENSE in the project root for license information.

using System;
using UnityEngine;
using UnityEngine.VR.WSA.Input;

namespace HoloToolkit.Unity
{
/// <summary>
/// GestureManager creates a gesture recognizer and signs up for a tap gesture.
/// When a tap gesture is detected, GestureManager uses GazeManager to find the game object.
/// GestureManager then sends a message to that game object.
/// </summary>
[RequireComponent(typeof(GazeManager))]
public partial class GestureManager : Singleton<GestureManager>
{
/// <summary>
/// Key to press in the editor to select the currently gazed hologram
/// </summary>
public KeyCode EditorSelectKey = KeyCode.Space;

/// <summary>
/// To select even when a hologram is not being gazed at,
/// set the override focused object.
/// If its null, then the gazed at object will be selected.
/// </summary>
public GameObject OverrideFocusedObject
{
get; set;
}

public bool IsManipulating { get; private set; }
public Vector3 ManipulationPosition { get; private set; }

/// <summary>
/// Gets the currently focused object, or null if none.
/// </summary>
public GameObject FocusedObject
{
get { return focusedObject; }
}

private GestureRecognizer gestureRecognizer;
private GameObject focusedObject;

void Start()
{
// Create a new GestureRecognizer. Sign up for tapped events.
gestureRecognizer = new GestureRecognizer();
gestureRecognizer.SetRecognizableGestures(GestureSettings.Tap
| GestureSettings.DoubleTap
| GestureSettings.ManipulationTranslate);

gestureRecognizer.TappedEvent += GestureRecognizer_TappedEvent;
//订阅Manipulation gesture事件
gestureRecognizer.ManipulationStartedEvent += GestureRecognizer_ManipulationStartedEvent;
gestureRecognizer.ManipulationUpdatedEvent += GestureRecognizer_ManipulationUpdatedEvent;
gestureRecognizer.ManipulationCompletedEvent += GestureRecognizer_ManipulationCompletedEvent;
gestureRecognizer.ManipulationCanceledEvent += GestureRecognizer_ManipulationCanceledEvent;

// Start looking for gestures.
gestureRecognizer.StartCapturingGestures();
}

private void GestureRecognizer_ManipulationStartedEvent(InteractionSourceKind source, Vector3 cumulativeDelta, Ray headRay)
{
//当被关注的对象非空时，设置初始位置
if (HandsManager.Instance.FocusedGameObject != null)
{
IsManipulating = true;

ManipulationPosition = cumulativeDelta;

HandsManager.Instance.FocusedGameObject.SendMessageUpwards("PerformManipulationStart", cumulativeDelta);
}
}

private void GestureRecognizer_ManipulationUpdatedEvent(InteractionSourceKind source, Vector3 cumulativeDelta, Ray headRay)
{
//当被关注的对象非空时，更新新的位置
if (HandsManager.Instance.FocusedGameObject != null)
{
IsManipulating = true;

ManipulationPosition = cumulativeDelta;

HandsManager.Instance.FocusedGameObject.SendMessageUpwards("PerformManipulationUpdate", cumulativeDelta);
}
}

private void GestureRecognizer_ManipulationCompletedEvent(InteractionSourceKind source, Vector3 cumulativeDelta, Ray headRay)
{
IsManipulating = false;
}

private void GestureRecognizer_ManipulationCanceledEvent(InteractionSourceKind source, Vector3 cumulativeDelta, Ray headRay)
{
IsManipulating = false;
}

private void OnTap()
{
if (focusedObject != null)
{
focusedObject.SendMessage("OnTap");
}
}

private void OnDoubleTap()
{
if (focusedObject != null)
{
focusedObject.SendMessage("OnDoubleTap");
}
}

private void GestureRecognizer_TappedEvent(InteractionSourceKind source, int tapCount, Ray headRay)
{
if (tapCount == 1)
{
OnTap();
}
else
{
OnDoubleTap();
}
}

void LateUpdate()
{
GameObject oldFocusedObject = focusedObject;

if (GazeManager.Instance.Hit &&
OverrideFocusedObject == null &&
GazeManager.Instance.HitInfo.collider != null)
{
// If gaze hits a hologram, set the focused object to that game object.
// Also if the caller has not decided to override the focused object.
focusedObject = GazeManager.Instance.HitInfo.collider.gameObject;
}
else
{
// If our gaze doesn't hit a hologram, set the focused object to null or override focused object.
focusedObject = OverrideFocusedObject;
}

//if (focusedObject != oldFocusedObject)
//{
//    // If the currently focused object doesn't match the old focused object, cancel the current gesture.
//    // Start looking for new gestures.  This is to prevent applying gestures from one hologram to another.
//    gestureRecognizer.CancelGestures();
//    gestureRecognizer.StartCapturingGestures();
//}
}

void OnDestroy()
{
gestureRecognizer.StopCapturingGestures();
//取消订阅
gestureRecognizer.TappedEvent -= GestureRecognizer_TappedEvent;
gestureRecognizer.ManipulationStartedEvent -= GestureRecognizer_ManipulationStartedEvent;
gestureRecognizer.ManipulationUpdatedEvent -= GestureRecognizer_ManipulationUpdatedEvent;
gestureRecognizer.ManipulationCompletedEvent -= GestureRecognizer_ManipulationCompletedEvent;
gestureRecognizer.ManipulationCanceledEvent -= GestureRecognizer_ManipulationCanceledEvent;
}
}
}

3、修改CubeScript.cs，添加物体平移函数，计算相对位移，然后进行更新物体的新的位置

using UnityEngine;
using System.Collections;
using HoloToolkit.Unity;

public class CubeScript : MonoBehaviour {

private Vector3 manipulationPreviousPosition;

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {

}

void PerformManipulationStart(Vector3 position)
{
//设置初始位置
manipulationPreviousPosition = position;
}

void PerformManipulationUpdate(Vector3 position)
{
if (GestureManager.Instance.IsManipulating)
{
//计算相对位移，然后更新物体的位置
Vector3 moveVector = Vector3.zero;
moveVector = position - manipulationPreviousPosition;
manipulationPreviousPosition = position;
transform.position += moveVector;
}
}

private void OnTap()
{
gameObject.GetComponent<MeshRenderer>().material.color = Color.blue;
}

private void OnDoubleTap()
{
gameObject.GetComponent<MeshRenderer>().material.color = Color.green;
}
}

4、运行测试

将凝视射线投射到cube上，举起右手使食指和拇指碰触在一起，然后进行左右移动，可以看到物体的位置将发生变化（在模拟器上不是很明显）

平移前



平移后，物体的相对位置发生变动