Unity ARKit Plugin 分析

下载地址 https://www.assetstore.unity3d.com/en/#!/content/92515

可以看随时查Unity-ARKit-Plugin的项目进展:
https://bitbucket.org/Unity-Technologies/unity-arkit-plugin/src/aa4933787df366c2d3ab15f65a8ceed57f23f1a6?at=default

首先看Unity-ARKit-Plugin的三个文档：

1.README.md:

两个核心文件：

/Assets/Plugins/iOS/UnityARKit/NativeInterface/ARSessionNative.mm

/Assets/Plugins/iOS/UnityARKit/NativeInterface/UnityARSessionNativeInterface.cs

包含下面重要API:

public void RunWithConfigAndOptions(ARKitWorldTackingSessionConfiguration config,UnityARSessionRunOption runOptions)

public void RunWithConfig(ARKitWorldTackingSessionConfiguration config)

public void Pause()

public List HitTest(ARPoint point,ARHitTestResultType types)

public ARTextureHandles GetARVideoTextureHandles()

public float GetARAmbientIntensity()

public int GetARTrackingQuality()

还有delegate:

public delegate void ARFrameUpdate(UnityARCamera camera)

public delegate void ARAnchorAdded(ARPlaneAnchor anchorData)

public delegate void ARAnchorUpdated(ARPlaneAnchor anchorData)

public delegate void ARAnchorRemoved(ARPlaneAnchor anchorData)

public delegate void ARSessionFailed(string error)

一些回调：

public static event ARFrameUpdate ARFrameUpdatedEvent;

public static event ARAnchorAdded ARAnchorAddedEvent;

public static event ARAnchorUpdated ARAnchorUpdatedEvent;

public static event ARAnchorRemoved ARAnchorRemovedEvent;

public static event ARAnchorAdded ARUserAnchorAddedEvent;

public static event ARAnchorUpdated ARUserAnchorUpdatedEvent;

public static event ARAnchorRemoved ARUserAnchorRemovedEvent;

public static event ARSessionCallback ARSessionInterruptedEvent;

public static event ARSessionCallback ARSessioninterruptionEndedEvent;

public static event ARSessionTrackingChanged ARSessionTrackingChangedEvent;

2. TUTORIAL.txt

一些要点作如下总结：

1>一切都从session开始，在文件UnityARCameraManager.cs中有

m_session = UnityARSessionNativeInterface.GetARSessionNativeInterface();

2> ARSession的config根据精度不同分为

ARKitWorldTrackingSessionConfiguration(6DOF)和ARKitSessionConfiguration(3DOF)，

这也是UnityARCameraManager.cs和AR3DOFCameraManager.cs两个文件的原因。

3>想要获取相机的位置，可以使用

Matrix4x4 matrix = m_session.GetCameraPose();

camera.transform.localPosition = UnityARMatrixOps.GetPosition(matrix);

camera.transform.localRotation = UnityARMatrixOps.GetRotation(matrix);

同样代码在UnityARCameraManager.cs中。

4> UnityARVideo.cs相机上组件，使用YUVMaterial shader渲染视频纹理。

5> UnityARHitTestExample处理Hit事件，获得Hit与接触平面的相交坐标，可以关联任何GameObject，Hit中的坐标可以控制相关GameObject.

6>可用使用UnityARAnchorManager执行AddAnchor,RemoveAnchor,UpdateAnchor操作。

7> PointCloudParticleExample，显示PointCloud的小黄点。

8> UnityARAmbient,ARKit光照亮度向Unity亮度的转化,Light的组件。

9> UnityARUserAnchorComponent用来移除用户自己添加的ARUserAnchor。

10>重要事件的回调还得去看UnityARSessionNativeInterface.cs

3. SCENES.txt

对Example中给出了Scene进行了介绍

UnityARKitScene.unity：最小场景的ARkit功能演示；

UnityParticlePainter.unity：空间粒子系统画点;

UnityARBallz.unity:平面小球移动与碰撞;

UnityARShadows.unity:在平面显示物体的阴影;

UnityAROcclusion.unity:遮光材料遮挡物体;;

UnityARUserAnchorScene.unity:通过Anchor添加删除物体;

### UnityARKitScene.unity

### UnityParticlePainter.unity

### UnityAROcclusion.unity
效果描述:出现立方体，点击出现小人，场景出现Cloud黄点，但没有显示平面

### UnityARShadows.unity

### UnityARBallz.unity

### AddRemoveAnchorScene.unity

效果描述:点击创建黑白网格立方体,4秒钟后消失

## 重要文件分析

Directional light

类型是Directional,绑定UnityARAmbient.cs

void UpdateAmbientIntensity(UnityARCamera camera)

{

// Convert ARKit intensity to Unity intensity

// ARKit ambient intensity ranges 0-2000

// Unity ambient intensity ranges 0-8(for over-bright lights)

float newai = camera.ambientIntensity;

l.intensity = newai / 1000.0f;

}

Main Camera