Cardboard VR开发，Gaze操作实现VR的目选效果
发表于2018-05-12
CardBoard应该是目前VR市场上最廉价的”VR头显”，虽然它廉价，但并不会阻碍大家针对Cardboard开发相应的VR应用，下面就来看看通过Gaze操作实现VR的目选效果。
由于Cardboard没什么按键，所以选择之类的事情只能用目选来进行，那怎么实现目选呢？可以想象一下，目选无非就是两部分，a：旋转读条；b、确认选择。
但是有一点，两部分分开来做那很简单啦，但是怎么放到一起呢？
首先，我们先来看看该部分原本给你提供的代码：Teleport.cs
// Copyright 2014 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// [url=http://www.apache.org/licenses/LICENSE-2.0]http://www.apache.org/licenses/LICENSE-2.0[/url]
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
using UnityEngine;
using System.Collections;
[RequireComponent(typeof(Collider))]
public class Teleport : MonoBehaviour, ICardboardGazeResponder ｛
private Vector3 startingPosition;
void Start() ｛
startingPosition = transform.localPosition;
SetGazedAt(false);
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void LateUpdate() ｛
Cardboard.SDK.UpdateState();
if (Cardboard.SDK.BackButtonPressed) ｛
Application.Quit();
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public void SetGazedAt(bool gazedAt) ｛
GetComponent<Renderer>().material.color = gazedAt ? Color.green : Color.red;
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public void Reset() ｛
transform.localPosition = startingPosition;
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public void ToggleVRMode() ｛
Cardboard.SDK.VRModeEnabled = !Cardboard.SDK.VRModeEnabled;
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public void ToggleDistortionCorrection() ｛
switch(Cardboard.SDK.DistortionCorrection) ｛
case Cardboard.DistortionCorrectionMethod.Unity:
Cardboard.SDK.DistortionCorrection = Cardboard.DistortionCorrectionMethod.Native;
break;
case Cardboard.DistortionCorrectionMethod.Native:
Cardboard.SDK.DistortionCorrection = Cardboard.DistortionCorrectionMethod.None;
break;
case Cardboard.DistortionCorrectionMethod.None:
default:
Cardboard.SDK.DistortionCorrection = Cardboard.DistortionCorrectionMethod.Unity;
break;
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public void ToggleDirectRender() ｛
Cardboard.Controller.directRender = !Cardboard.Controller.directRender;
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public void TeleportRandomly() ｛
Vector3 direction = Random.onUnitSphere;
direction.y = Mathf.Clamp(direction.y, 0.5f, 1f);
float distance = 2 * Random.value + 1.5f;
transform.localPosition = direction * distance;
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#region ICardboardGazeResponder implementation
/// Called when the user is looking on a GameObject with this script,
/// as long as it is set to an appropriate layer (see CardboardGaze).
public void OnGazeEnter() ｛
SetGazedAt(true);
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/// Called when the user stops looking on the GameObject, after OnGazeEnter
/// was already called.
public void OnGazeExit() ｛
SetGazedAt(false);
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// Called when the Cardboard trigger is used, between OnGazeEnter
/// and OnGazeExit.
public void OnGazeTrigger() ｛
TeleportRandomly();
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#endregion
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其实大部分代码我都从头到尾稍稍读了一遍，其实接口已经清楚地给我们放出来了，就是这块代码。代码中有一个SetGazedAt的方法，该方法就是当你水平目视前方的物体算作你选中的物体，官方demo里是当你目视一个cube时把该cube的颜色由红色换为绿色。
二、好的，突破口已经找到了，我们来看看怎么实现旋转读条的效果：
其实很简单，研究过UI的人应该都明白，就是一个很简单的遮罩。
放一个画布canvas，然后创建一个image命名为imageBg作为背景，再创建一个image命名为imageFill作为内容，然后复制一个imageFill，选color属性调成半透明，颜色改成灰色，image Type选择Filled，大小都调合适了。然后就做成了，如图：
三、把Teleport.cs拖到imageBg上，我们再来看刚刚的代码部分，按常理来说，点击选中面板中可以直接添加一个button属性就可以实现，但是我们现在要的是目选，所以就要自己来判断了，其实也不难，也就是一个触发器的问题。
public void SetGazedAt(bool gazedAt) ｛
isStartTime = gazedAt ? true : false;
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上面这个函数前面加上public
在imageBg下添加一个Event Trigger，添加Pointer Enter和Pointer Exit，分别对应SetGazeAt方法的两个值
在初始化里获取imageFill的image组件，设置fillAmount的初始值为零。
在update里利用计时器来控制旋转读条的快慢，并在读完时刻判断目选的选中状态。
修改后的全部代码如下：
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class TeleportGUI : MonoBehaviour, ICardboardGazeResponder ｛
public float coldTime = 1;
private Image imagefill;
private float timer = 0;
private bool isStartTime = false;
private double minNum = 0.01;
private double maxNum = 0.02;
private bool isNext = false;
public Text index;
int IndexInt = 0;
string IndexStr = "";
// Use this for initialization
void Start () ｛
imagefill = transform.Find ("Imagefill").GetComponent<Image> ();
imagefill.fillAmount = 0;
SetGazedAt (false);
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void LateUpdate() ｛
Cardboard.SDK.UpdateState();
if (Cardboard.SDK.BackButtonPressed) ｛
Application.Quit();
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public void SetGazedAt(bool gazedAt) ｛
isStartTime = gazedAt ? true : false;
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// Update is called once per frame
void Update () ｛
if (isStartTime) ｛
timer += Time.deltaTime;
imagefill.fillAmount = (coldTime - timer) / coldTime;//从1到0减小
if (timer >= coldTime) ｛
imagefill.fillAmount = 0;
timer = 0;
isStartTime = false;
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if(!isStartTime) ｛
timer = 0;
imagefill.fillAmount = 0;
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if (imagefill.fillAmount < maxNum && imagefill.fillAmount >minNum) ｛
isNext = true;
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if (isNext) ｛
ChooseManageScript.Instance.A_Btn ();
index = GameObject.Find("IndexBackground").transform.Find ("Index").GetComponent<Text> ();
IndexInt = int.Parse(index.text);
IndexInt += 1;
IndexStr = IndexInt.ToString();
index.text = IndexStr;
isNext = false;
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public void TeleportRandomly() ｛
Vector3 direction = Random.onUnitSphere;
direction.y = Mathf.Clamp(direction.y, 0.5f, 1f);
float distance = 2 * Random.value + 1.5f;
transform.localPosition = direction * distance;
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#region ICardboardGazeResponder implementation
/// Called when the user is looking on a GameObject with this script,
/// as long as it is set to an appropriate layer (see CardboardGaze).
public void OnGazeEnter() ｛
SetGazedAt(true);
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/// Called when the user stops looking on the GameObject, after OnGazeEnter
/// was already called.
public void OnGazeExit() ｛
SetGazedAt(false);
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// Called when the Cardboard trigger is used, between OnGazeEnter
/// and OnGazeExit.
public void OnGazeTrigger() ｛
TeleportRandomly();
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#endregion
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来自：https://blog.csdn.net/yushengqi12345/article/details/77569658