Unity基礎篇：射線檢測Physics.Raycast相關功能整合。

我們先看射線的相關文檔。

public static bool RayCast(Vector3 origin, Vector3 direction, float maxDistance = Mathf.Infinity, int layerMask = DefaultRaycastLayers, QueryTriggerInteraction queryTriggerInteraction = QueryTriggerInteraction.UseGlobal);

public static bool Raycast(Vector3 origin, Vector3 direction, out RaycastHit hitInfo, float maxDistance = Mathf.Infinity, int layerMask = DefaultRaycastLayers, QueryTriggerInteraction queryTriggerInteraction = QueryTriggerInteraction.UseGlobal);

public static bool Raycast(Ray ray, float maxDistance = Mathf.Infinity, int layerMask = DefaultRaycastLayers, QueryTriggerInteraction queryTriggerInteraction = QueryTriggerInteraction.UseGlobal);

public static bool Raycast(Ray ray, out RaycastHit hitInfo, float maxDistance = Mathf.Infinity, int layerMask = DefaultRaycastLayers, QueryTriggerInteraction queryTriggerInteraction = QueryTriggerInteraction.UseGlobal);

Parameters 參數

origin	The starting point of the ray in world coordinates. 在世界坐标，射線的起始點。
direction	The direction of the ray. 射線的方向。
distance	The length of the ray. 射線的長度。
layermask	A Layer mask that is used to selectively ignore colliders when casting a ray. 投射射線，選擇投射的層蒙版。
queryTriggerInteraction	Specifies whether this query should hit Triggers. 指定是否查詢碰到觸發器。

ray	The starting point and direction of the ray. 射線的起點和方向

hitInfo

If true is returned, hitInfo will contain more information about where the collider was hit (See Also: RaycastHit).

hitInfo将包含碰到器碰撞的更多資訊。

RaycastHit 射線投射碰撞資訊

struct in UnityEngine

Description 描述

Structure used to get information back from a raycast.

該結構用來擷取射線投射傳回的資訊。

See Also: Physics.Raycast, Physics:Physics.Linecast, Physics.RaycastAll.

Variables 變量

barycentricCoordinate	The barycentric coordinate of the triangle we hit. 碰到的三角形的重心坐标。
collider	The Collider that was hit. 碰到的碰撞器。
distance	The distance from the ray's origin to the impact point. 從射線的原點到觸碰點的距離。
lightmapCoord	The uv lightmap coordinate at the impact point. 在觸碰點的UV光照貼圖的坐标。
normal	The normal of the surface the ray hit. 射線觸碰表面的法線。
point	The impact point in world space where the ray hit the collider. 在世界坐标空間，射線碰到碰撞器的接觸點。
rigidbody	The Rigidbody of the collider that was hit. If the collider is not attached to a rigidbody then it is null. 碰到的該碰撞器上的剛體。如果碰撞器上沒有附加剛體，那麼傳回null。
textureCoord	The uv texture coordinate at the impact point. 在觸碰點的UV紋理坐标。
textureCoord2	The secondary uv texture coordinate at the impact point. 在接觸點處的第二套UV紋理坐标。
transform	The Transform of the rigidbody or collider that was hit. 碰到的該剛體或碰撞器的變換。
triangleIndex	The index of the triangle that was hit. 碰到的三角形的索引。

Returns 傳回

bool True when the ray intersects any collider, otherwise false.

當光線投射與任何碰撞器交叉時為真，否則為假。

預設參數：1.layerMask參數預設為DefaultRaycastLayers，

2.distance被預設為正無窮，

3. queryTriggerInteraction 被預設為QueryTriggerInteraction.UseGlobal

什麼意思呢？我們來看