手把手教你做个AR涂涂乐

前段时间公司有一个AR涂涂乐的项目,虽然之前接触过AR也写过小Demo,但是没有完整开发过AR项目.不过经过1个多星期的学习,现在已经把项目相关的技术都学会了,在此向互联网上那些乐于分享的程序员前辈们致敬.学习的过程中我发现好多博客只有代码没有讲解,在这里我就写一个详细一点的涂涂乐教程吧.

一.AR涂涂乐原理

目前市场上所有的AR产品中,涂涂乐是一个做的比较成功的产品,因为其形象 生动 新奇的特点,在早教行业内很受欢迎.其实AR涂涂乐的原理非常简单,就是把被当作画画工具的识别图上的颜色材质渲染到空白的模型上.

二.制作流程

我大概总结了下从模型到AR应用涉及到的具体流程,如下:

  1. 美术制作AR应用中需要用到的模型和动画
  2. 模型制作好之后,对照识别图上的模型外形匹配好UV
  3. UV匹配好之后把模型和识别图交付程序,程序登录Vuforia官网添加证书和目标数据
  4. 程序把Vuforia插件和目标数据分别下好并导入工程
  5. 删除默认场景中的摄像机,添加ARCamera和ImageTarget到场景并配置好参数
  6. 把涂涂乐需要用到的模型放入场景,把模型的动画切好
  7. 求识别图4个顶点的位置,获取一帧图像,把这些参数传给Shader,Shader处理过后,识别图上的颜色就渲染到模型上了
  8. 导出的手机,我这里是安卓平台

三.图文教程

这里以我最近写的项目为例:

1.美术不是自己亲自做的,就写下我当时做项目时对美术的要求吧:

  • UV要展好,和识别图匹配好
  • 带动画的模型要保持独立,不能和其他模型在一起
  • 模型动画要有周期性2遍为一个周期
  • 识别图要对比强烈
  • 命名规范要有意义同一模型的不同组件要分组
  • 单位M
  • 格式FBX

交付:

  • 模型:

    2.png

  • 识别图:

    1.png

这个模型只有花是用来画画的,因此识别图是一个空白的花.

2.Vuforia准备工作(许可证 和 识别图数据)

  • 没有注册过的先注册下,Vuforia注册时要注意的一点是密码要包含大小写和特殊符号
  • 注册后点击Develop --->Add License Key

3.png

  • 正常测试选Development就行了,然后取个名字点Next

4.png

  • 然后确认就好了

5.png

  • 这里的License Key是待会项目中要用到的 先用记事本保存下来备用

Paste_Image.png

  • 到了添加识别图的时候了,先创建一个Target Database
    Paste_Image.png

Paste_Image.png

  • 然后点击刚才创建的Target Database

Paste_Image.png

  • 添加识别图

Paste_Image.png

  • 静静等待 不要关闭

Paste_Image.png

  • 下载识别图数据备用

Paste_Image.png

  • 下载Vuforia插件备用

Paste_Image.png

3.Unity配置阶段

  • 配置安卓开发环境(之前写过的博客,很具体)电梯

  • 转换开发平台(不提前转换导出时有可能会报错)

Paste_Image.png

  • 依次导入Vuforia插件包,识别图数据包,美术资源

Paste_Image.png

  • 删除场景中的Camera,在场景中添加AR Camera和Image Target

Paste_Image.png

  • 配置AR Camera

Paste_Image.png

  • 配置Image Target

Paste_Image.png

  • 把模型拖入Image Target并调整好位置

Paste_Image.png

4.编程阶段

总体思想:编程阶段做的主要工作是把识别图上的材质信息经过计算赋给模型,这里因为动画的原因,每个模型可能涉及很多单个小模块,每个单个的模块都要经过这个计算,在这里,花的7个花瓣是独立的,也就需要7次运算.

  • 核心代码
using UnityEngine;
using Vuforia;
using System.Collections;

public class ARRender : MonoBehaviour
{

    public GameObject Scene;

    private Animator flowerAnimator;
    
    //七色花的七个花瓣
    public GameObject flower1;
    public GameObject flower2;
    public GameObject flower3;
    public GameObject flower4;
    public GameObject flower5;
    public GameObject flower6;
    public GameObject flower7;

    private Texture2D texture;
    //申请Texture2D变量储存屏幕截图

    private int screenWidth;
    //保存屏幕宽度
    private int screenHeight;
    //保存屏幕高度

    //拾取真正贴图的四个点的坐标
    Vector3 targetAnglePoint1;
    //左上角坐标
    Vector3 targetAnglePoint2;
    //左下角坐标
    Vector3 targetAnglePoint3;
    //右上角坐标
    Vector3 targetAnglePoint4;
    //右下角坐标

    public GameObject plane;
    //储存确定贴图大小的面片物体

    Vector2 halfSize;
    //记录plane宽高的一半值


    void Start()
    {

        screenWidth = Screen.width;
        //屏幕宽
        screenHeight = Screen.height;
        //屏幕高
        
        texture = new Texture2D(screenWidth, screenHeight, TextureFormat.RGB24, false);//实例化空纹理

        flowerAnimator = this.GetComponent<Animator>();

    }


    //截屏函数
    public void ScreenShot()
    {
       Scene.SetActive(true);
       
        flowerAnimator.SetTrigger("FlowerRainbow");
        

        texture.ReadPixels(new Rect(0, 0, screenWidth, screenHeight), 0, 0);
        //读取屏幕像素信息
        texture.Apply();
        //存储为纹理数据

        halfSize = new Vector2(plane.GetComponent<MeshFilter>().mesh.bounds.size.x, plane.GetComponent<MeshFilter>().mesh.bounds.size.z) * 50.0f*0.5f;
        //获取Plane的长宽的一半值

        //确定真实贴图的世界坐标
        targetAnglePoint1 = transform.parent.position + new Vector3(-halfSize.x, 0, halfSize.y);
        targetAnglePoint2 = transform.parent.position + new Vector3(-halfSize.x, 0, -halfSize.y);
        targetAnglePoint3 = transform.parent.position + new Vector3(halfSize.x, 0, halfSize.y);
        targetAnglePoint4 = transform.parent.position + new Vector3(halfSize.x, 0, -halfSize.y);

        //获取VP值
        Matrix4x4 P = GL.GetGPUProjectionMatrix(Camera.main.projectionMatrix, false);
        Matrix4x4 V = Camera.main.worldToCameraMatrix;
        Matrix4x4 VP = P * V;

        //给地球的Shader传递贴图四个点的世界坐标,VP,以及贴图
        flower1.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower1.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower1.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower1.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower1.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower1.GetComponent<Renderer>().material.mainTexture = texture;

        flower2.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower2.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower2.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower2.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower2.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower2.GetComponent<Renderer>().material.mainTexture = texture;

        flower3.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower3.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower3.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower3.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower3.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower3.GetComponent<Renderer>().material.mainTexture = texture;

        flower4.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower4.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower4.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower4.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower4.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower4.GetComponent<Renderer>().material.mainTexture = texture;

        flower5.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower5.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower5.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower5.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower5.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower5.GetComponent<Renderer>().material.mainTexture = texture;

        flower6.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower6.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower6.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower6.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower6.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower6.GetComponent<Renderer>().material.mainTexture = texture;

        flower7.GetComponent<Renderer>().material.SetVector("_Uvpoint1", new Vector4(targetAnglePoint1.x, targetAnglePoint1.y, targetAnglePoint1.z, 1f));
        flower7.GetComponent<Renderer>().material.SetVector("_Uvpoint2", new Vector4(targetAnglePoint2.x, targetAnglePoint2.y, targetAnglePoint2.z, 1f));
        flower7.GetComponent<Renderer>().material.SetVector("_Uvpoint3", new Vector4(targetAnglePoint3.x, targetAnglePoint3.y, targetAnglePoint3.z, 1f));
        flower7.GetComponent<Renderer>().material.SetVector("_Uvpoint4", new Vector4(targetAnglePoint4.x, targetAnglePoint4.y, targetAnglePoint4.z, 1f));
        flower7.GetComponent<Renderer>().material.SetMatrix("_VP", VP);
        flower7.GetComponent<Renderer>().material.mainTexture = texture;        
    }
}
  • Shader
Shader "AR paint/ToMaterial" {
    Properties {
        _MainTex ("Base (RGB)", 2D) = "white" {}
        _Uvpoint1("point1", Vector) = (0 , 0 , 0 , 0)
        _Uvpoint2("point2", Vector) = (0 , 0 , 0 , 0)
        _Uvpoint3("point3", Vector) = (0 , 0 , 0 , 0)
        _Uvpoint4("point4", Vector) = (0 , 0 , 0 , 0)

    }
    SubShader {
        Tags { "Queue"="Transparent" "RenderType"="Transparent" }
        LOD 200

        Pass{
            Blend SrcAlpha OneMinusSrcAlpha

            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _Uvpoint1;
            float4 _Uvpoint2;
            float4 _Uvpoint3;
            float4 _Uvpoint4;
            float4x4 _VP;

            struct v2f {
                float4  pos : SV_POSITION;
                float2  uv : TEXCOORD0;
                float4  fixedPos : TEXCOORD2;
            } ;

            v2f vert (appdata_base v)
            {
                v2f o;
                o.pos = mul(UNITY_MATRIX_MVP,v.vertex);
                o.uv = TRANSFORM_TEX(v.texcoord,_MainTex);
                
                float4 top = lerp(_Uvpoint1, _Uvpoint3, o.uv.x);
                float4 bottom = lerp(_Uvpoint2, _Uvpoint4, o.uv.x);
                float4 fixedPos = lerp(bottom, top, o.uv.y);
                o.fixedPos = ComputeScreenPos(mul(UNITY_MATRIX_VP, fixedPos));
                return o;
            }

            float4 frag (v2f i) : COLOR
            {
                
                float4 top = lerp(_Uvpoint1, _Uvpoint3, i.uv.x);
                float4 bottom = lerp(_Uvpoint2, _Uvpoint4, i.uv.x);
                float4 fixedPos = lerp(bottom, top, i.uv.y);
                fixedPos = ComputeScreenPos(mul(_VP, fixedPos));
                return tex2D(_MainTex, fixedPos.xy / fixedPos.w);
                
            }
            ENDCG
        }
    }
    //FallBack "Diffuse"
}
  • 首先在ImageTarget下新建一个Plane和识别图大小一致,核心代码的功能就是把场景中Plane(也就是识别图)的世界坐标转换到屏幕坐标,然后截图形成纹理,最后把这些数据传给Shader处理.

Paste_Image.png

  • 把模型拖入ImageTarget,装饰场景也拖进去先隐藏,然后把需要渲染的模块拖入ARRender的代码参数,然后新建一个材质,Shader选择ARpaint/ToMaterial,把这个材质赋给所有要涂色渲染的模块,也就是7个花瓣.
  • 新建一个Button,添加事件拖入Flower,方法选择ScreenShot
  • 导出安装包到手机,测试,这是我的测试结果:

85.jpg

8.png

  • 关于动画

  • 动画拿到之后根据需要进行切割并Apply

Paste_Image.png

  • 新建一个动画控制器,把刚才切好的动画拖到动画状态机里面,右键建立Transition,Parameters选项卡中创建Trigger,这样就可以在程序中控制动画了

  • 关于音效

  • 新建一个空物体,起名Audio
  • 添加AudioSource组件
  • 拖入ImageTarget
  • 找到ImageTarget下的 DefaultTrackableEventHandler 脚本 声明AudioSource变量然后分别在 OnTrackingFound() 和 OnTrackingLost()这两个方法里添加声音暂停和开始方法

public class DefaultTrackableEventHandler : MonoBehaviour,
                                                ITrackableEventHandler
    {
        public AudioSource clothesAudioSource;
        #region PRIVATE_MEMBER_VARIABLES
 
        private TrackableBehaviour mTrackableBehaviour;
    
        #endregion // PRIVATE_MEMBER_VARIABLES



        #region UNTIY_MONOBEHAVIOUR_METHODS
    
        void Start()
        {
            mTrackableBehaviour = GetComponent<TrackableBehaviour>();
            if (mTrackableBehaviour)
            {
                mTrackableBehaviour.RegisterTrackableEventHandler(this);
            }
        }

        #endregion // UNTIY_MONOBEHAVIOUR_METHODS



        #region PUBLIC_METHODS

        /// <summary>
        /// Implementation of the ITrackableEventHandler function called when the
        /// tracking state changes.
        /// </summary>
        public void OnTrackableStateChanged(
                                        TrackableBehaviour.Status previousStatus,
                                        TrackableBehaviour.Status newStatus)
        {
            if (newStatus == TrackableBehaviour.Status.DETECTED ||
                newStatus == TrackableBehaviour.Status.TRACKED ||
                newStatus == TrackableBehaviour.Status.EXTENDED_TRACKED)
            {
                OnTrackingFound();
            }
            else
            {
                OnTrackingLost();
            }
        }

        #endregion // PUBLIC_METHODS



        #region PRIVATE_METHODS


        private void OnTrackingFound()
        {
            //gameObject.transform.FindChild ("Earth").gameObject.SetActive (true);
            Renderer[] rendererComponents = GetComponentsInChildren<Renderer>(true);
            Collider[] colliderComponents = GetComponentsInChildren<Collider>(true);

            // Enable rendering:
            foreach (Renderer component in rendererComponents)
            {
                component.enabled = true;
            }

            // Enable colliders:
            foreach (Collider component in colliderComponents)
            {
                component.enabled = true;
            }
            if (!clothesAudioSource.isPlaying)
            {
               clothesAudioSource.Play(); 
            }
            

            Debug.Log("Trackable " + mTrackableBehaviour.TrackableName + " found");
        }


        private void OnTrackingLost()
        {
            Renderer[] rendererComponents = GetComponentsInChildren<Renderer>(true);
            Collider[] colliderComponents = GetComponentsInChildren<Collider>(true);

            // Disable rendering:
            foreach (Renderer component in rendererComponents)
            {
                component.enabled = false;
            }

            // Disable colliders:
            foreach (Collider component in colliderComponents)
            {
                component.enabled = false;
            }

            clothesAudioSource.Pause();

            Debug.Log("Trackable " + mTrackableBehaviour.TrackableName + " lost");
        }

        #endregion // PRIVATE_METHODS
    }
}
  • 关于对焦

    Vuforia默认不会自动对焦,新建一个脚本,把下面代码复制进去,把脚本拖到ARCamera上面就好了

using UnityEngine;
using System.Collections;

public class Duijiao : MonoBehaviour
{

    // Use this for initialization
    void Start()
    {
        GameObject ARCamera = GameObject.Find("ARCamera");

        Vuforia.CameraDevice.Instance.SetFocusMode(Vuforia.CameraDevice.FocusMode.FOCUS_MODE_CONTINUOUSAUTO);
    }

    // Update is called once per frame
    void Update()
    {
        Vuforia.CameraDevice.Instance.SetFocusMode(Vuforia.CameraDevice.FocusMode.FOCUS_MODE_CONTINUOUSAUTO);
    }
}
  • 关于多图识别

  • 设置目标上限

Paste_Image.png

  • 拖入更多的ImageTarget,每个ImageTarget下配置不同的识别图和模型就能多图识别了

Paste_Image.png

  • 测试结果

Paste_Image.png

由于还没有重构,代码比较丑陋,不过好处是适合新手,很好理解

posted @ 2017-03-20 23:01 乔高建 阅读(...) 评论(...) 编辑 收藏