不在图层蒙版中的 Unity 对象被光线投射击中 [重复]

Question

我正在使用光线投射来检测与可控层上的对象的碰撞。由于某种原因，不在可控层上的对象也会受到影响。这是我调用光线投射的代码。

if (Input.touches.Length > 0)
    {
        RaycastHit hit;
        if (Physics.Raycast(firstPersonCamera.ScreenPointToRay(Input.GetTouch(0).position), out hit, controllableLayer))
        {
            Debug.Log("Object hit");
            Debug.Log(hit.transform.gameObject.name);

            Touch touch = Input.GetTouch(0);

            GameObject objectHit = hit.transform.gameObject;

            if (dragging)
            {
                Vector3 cursorScreenPoint = new Vector3(touch.position.x, touch.position.y, screenPoint.z);
                Vector3 cursorPosition = firstPersonCamera.ScreenToWorldPoint(cursorScreenPoint) + offset;
                objectHit.transform.position = cursorPosition;
            }
            // Handle finger movements based on touch phase.
            switch (touch.phase)
            {
                // Record initial touch position.
                case TouchPhase.Began:
                    screenPoint = firstPersonCamera.WorldToScreenPoint(objectHit.transform.position);
                    offset = objectHit.transform.position - firstPersonCamera.ScreenToWorldPoint(new Vector3(touch.position.x, touch.position.y, screenPoint.z));
                    dragging = true;
                    break;

                // Determine direction by comparing the current touch position with the initial one.
                case TouchPhase.Moved:
                    break;

                // Report that a direction has been chosen when the finger is lifted.
                case TouchPhase.Ended:
                    dragging = false;
                    break;
            }
        }
        else
        {
            Debug.Log("Nothing hit");
        }
    }

这里也是我声明图层蒙版的地方

void Awake()
{
    firstPersonCamera = GameObject.Find("First Person Camera").GetComponent<Camera>();
    controllableLayer = LayerMask.NameToLayer("Controllable");
    Debug.Log(LayerMask.LayerToName(controllableLayer));
}

Answer 1

由于Layers使用位移，所以在raycasting时你必须这样做：

int layerMask = 1 << controllableLayer;
Physics.Raycast(firstPersonCamera.ScreenPointToRay(Input.GetTouch(0).position), out hit, layerMask)

否则，将controllableLayer 声明为整数并执行以下操作：

int controllableLayer ;

void Awake()
{
    controllableLayer = 1 << LayerMask.NameToLayer("Controllable");
}

void Update()
{
    // ...
    if( Physics.Raycast(firstPersonCamera.ScreenPointToRay(Input.GetTouch(0).position), out hit, controllableLayer) )
    {
        // ...
    }
}

检查这些链接：

1. https://answers.unity.com/questions/472886/use-layer-name-for-layermask-instead-of-layer-numb.html
2. https://gamedev.stackexchange.com/questions/132132/why-do-unity-layer-masks-need-to-use-bit-shifting