监听On_Drag需要注意一下三点：

1. Enable auto-select，[勾选].
   3d物体时能被触摸识别

2. pickable layers 3D ，[设置需要的层级].
   能够被触摸识别的3d物体层级

3. 相机Camera，[一定要设置]，界面或代码设置皆可.

    EasyTouch.AddCamera(_camera);
    EasyTouch.RemoveCamera(_camera);
   

EasyTouch Drag设置.png

On_Drag监听：

 EasyTouch.On_Drag += FurnitureTrigger.Instance.OnDrag;
 EasyTouch.On_Drag -= FurnitureTrigger.Instance.OnDrag;

 public void OnDrag(Gesture gesture)
 { 
    if (gesture.touchCount > 1 || gesture.pickedObject == null)
    {
        return;
    }
 }

注意事项解析：

private void CreateGesture(int touchIndex,EvtType message,Finger finger, SwipeDirection swipe, float swipeLength, Vector2 swipeVector)
{
    ...
    // Auto update picked object
    if (autoUpdatePickedObject && autoSelect){
        if (message != EvtType.On_Drag && message != EvtType.On_DragEnd && message != EvtType.On_DragStart){
            if (GetPickedGameObject(finger)){
                gesture.pickedObject = pickedObject.pickedObj;
                gesture.pickedCamera = pickedObject.pickedCamera;
                gesture.isGuiCamera = pickedObject.isGUI;
            }
            else{
                gesture.pickedObject = null;
                gesture.pickedCamera = null;
                gesture.isGuiCamera = false;
            }
        }
    }
    ...
}

为什么要设置相机Camera和pickable layers？

1. 在GetPickedGameObject中判断touchCameras.Count数量以及是否有有效的touchCamerastouchCameras[i].camera!=null && touchCameras[i].camera.enabled

2. 在GetGameObjectAt中Physics.Raycast( ray, out hit,float.MaxValue,mask )射线检测mask层 (pickable layers，LayerMask mask = pickableLayers3D;)，获取并设置pickedObjpickedObject.pickedObj = hit.collider.gameObject

3. 在OneFinger中，若pickedObject 存在，则说明是Drag（If an object is selected we drag）；否则是Swipe。
   if (fingers[fingerIndex].pickedObject){ fingers[fingerIndex].gesture = GestureType.Drag;}

private bool GetPickedGameObject(Finger finger, bool isTowFinger=false){

    ...
    
    if (touchCameras.Count>0){
        for (int i=0;i<touchCameras.Count;i++){
            if (touchCameras[i].camera!=null && touchCameras[i].camera.enabled){

                Vector2 pos=Vector2.zero;
                if (!isTowFinger){
                    pos = finger.position;
                }
                else{
                    pos = twoFinger.position;
                }

                
                if (GetGameObjectAt( pos, touchCameras[i].camera,touchCameras[i].guiCamera)){
                        return true;
                    }
            }
        }
    }
    else{
        Debug.LogWarning("No camera is assigned to EasyTouch"); 
    }
    return false;     
}


private bool GetGameObjectAt(Vector2 position, Camera cam, bool isGuiCam){

    Ray ray = cam.ScreenPointToRay( position );
    RaycastHit hit;

    if (enable2D){
        
        LayerMask mask2d = pickableLayers2D;
        RaycastHit2D[] hit2D = new RaycastHit2D[1];
        if (Physics2D.GetRayIntersectionNonAlloc( ray,hit2D,float.PositiveInfinity,mask2d)>0){
            pickedObject.pickedCamera = cam;
            pickedObject.isGUI = isGuiCam;
            pickedObject.pickedObj = hit2D[0].collider.gameObject;
            return true;
        }
    }
    
    LayerMask mask = pickableLayers3D;
    
    if( Physics.Raycast( ray, out hit,float.MaxValue,mask ) ){
        pickedObject.pickedCamera = cam;
        pickedObject.isGUI =isGuiCam;
        pickedObject.pickedObj = hit.collider.gameObject;
        return true;
    }

    return false;
}

private void OneFinger(int fingerIndex){
    ...
    // If an object is selected we drag
    if (fingers[fingerIndex].pickedObject){
      fingers[fingerIndex].gesture = GestureType.Drag;
    }
    ...
}