| ray | 定义要测试的原点和方向的 3D 射线。 |
| distance | 射线的最大投射距离。 |
| layerMask | 过滤器，用于仅在特定层上检测碰撞体。 |
| results | 用于接收结果的数组。 |
int 返回的结果数量。
Cast a 3D ray against the Colliders in the Scene returning the Colliders along the ray. Note: This method will be deprecated in a future build and it is recommended to use GetRayIntersection instead.
This is useful for finding Colliders intersecting an arbitrary 3D ray.
This function is similar to the GetRayIntersectionAll function except that the results are returned in the supplied array. The integer return value is the number of objects that intersect the ray (possibly zero) but the results array will not be resized if it doesn't contain enough elements to report all the results. The significance of this is that no memory is allocated for the results and so garbage collection performance is improved when such calls are performed frequently. The Colliders will be placed in the returned array in order of distance from the start of the ray.
此外，该函数是一种 3D 交叉测试，因此 RaycastHit2D 中返回的任何碰撞法线都将为零。