Class BufferedRaycast

Namespace: mobisim.VR

Zero-allocation wrapper around Unity's Physics.RaycastNonAlloc and Physics.SphereCastNonAlloc APIs that stores results in a fixed-size array allocated once at construction time.

public class BufferedRaycast

Inheritance

object→BufferedRaycast

Examples

Allocate the instance once at component startup so the internal hit and distance arrays are never re-created at runtime. Call Int32}) with sortByDistance: true in the per-frame hot path; the results are returned via a zero-allocation iterator over the pre-allocated buffer rather than a freshly constructed RaycastHit[] as Physics.RaycastAll would produce.

public class GazeCaster : MonoBehaviour
{
    // Allocated once; supports up to 10 simultaneous hits per cast — matching
    // the capacity used by VarjoEyeTrackingHandler for 200 Hz gaze sampling.
    private readonly BufferedRaycast _raycast = new BufferedRaycast(10);

    private void Update()
    {
        Ray gazeRay = new Ray(transform.position, transform.forward);

        // sortByDistance: true orders hits nearest-first with no List allocation;
        // the sort is performed in-place on the internal float[] distance buffer.
        foreach (RaycastHit hit in _raycast.Raycast(gazeRay, sortByDistance: true))
        {
            // Process hits in ascending distance order.
            Debug.Log($"Hit {hit.collider.name} at {hit.distance:F2} m");
        }
        // No GC pressure: _raycast reuses the same RaycastHit[] on every call.
    }
}

Remarks

Unity's convenience overloads (Physics.RaycastAll, Physics.SphereCastAll) return a newly allocated RaycastHit[] on every call. At the 200 Hz gaze-logging rate used by VarjoEyeTrackingHandler this produces 200 allocations per second, increasing GC pause frequency. BufferedRaycast fixes the array size at construction — the caller trades dynamic result counts for zero per-cast heap pressure.

The optional distance sort uses a companion float[] buffer and Array) on the slice that was actually filled, avoiding allocating a List for the sort step.

Constructors

BufferedRaycast(int)

Initializes a new instance of the BufferedRaycast class, allocating buffers for up to allowedSize hits.

public BufferedRaycast(int allowedSize)

Parameters

Name	Type	Description
allowedSize	int	The maximum number of hits to store per cast.

Methods

FilteredRaycast<T>(Ray, bool, float, int?)

Performs a raycast and returns components of type T attached to GameObjects hit by the raycast.

public IEnumerable<T> FilteredRaycast<T>(Ray ray, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
ray	Ray	The ray to cast.
sortByDistance	bool	If true, sorts hits by distance from the ray origin.
maxDistance	float	The maximum distance to cast the ray.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<T> — An enumerable of components of type T.

Type Parameters

Name	Type	Description
T		Type of component to retrieve from hit GameObjects.

FilteredRaycast<T>(Vector3, Vector3, bool, float, int?)

Performs a raycast and returns components of type T attached to GameObjects hit by the raycast.

public IEnumerable<T> FilteredRaycast<T>(Vector3 origin, Vector3 direction, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
origin	Vector3	The starting point of the ray.
direction	Vector3	The direction of the ray.
sortByDistance	bool	If true, sorts hits by distance from the origin.
maxDistance	float	The maximum distance to cast the ray.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<T> — An enumerable of components of type T.

Type Parameters

Name	Type	Description
T		Type of component to retrieve from hit GameObjects.

FilteredSphereCast<T>(Vector3, float, Vector3, bool, float, int?)

Performs a sphere cast and returns components of type T attached to GameObjects hit by the sphere cast.

public IEnumerable<T> FilteredSphereCast<T>(Vector3 origin, float radius, Vector3 direction, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
origin	Vector3	The starting point of the sphere cast.
radius	float	The radius of the sphere cast.
direction	Vector3	The direction to cast the sphere.
sortByDistance	bool	If true, sorts hits by distance from the origin.
maxDistance	float	The maximum distance to cast the sphere.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<T> — An enumerable of components of type T.

Type Parameters

Name	Type	Description
T		Type of component to retrieve from hit GameObjects.

FilteredSphereCast<T>(Ray, float, bool, float, int?)

Performs a sphere cast and returns components of type T attached to GameObjects hit by the sphere cast.

public IEnumerable<T> FilteredSphereCast<T>(Ray ray, float radius, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
ray	Ray	The ray to cast the sphere along.
radius	float	The radius of the sphere cast.
sortByDistance	bool	If true, sorts hits by distance from the ray origin.
maxDistance	float	The maximum distance to cast the sphere.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<T> — An enumerable of components of type T.

Type Parameters

Name	Type	Description
T		Type of component to retrieve from hit GameObjects.

Raycast(Ray, bool, float, int?)

Performs a raycast using the specified Ray and returns the hits.

public IEnumerable<RaycastHit> Raycast(Ray ray, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
ray	Ray	The ray to cast.
sortByDistance	bool	If true, sorts hits by distance from the ray origin.
maxDistance	float	The maximum distance to cast the ray.
layerMask	int?	Optional layer mask to filter raycast hits.

Returns

IEnumerable<RaycastHit> — An enumerable of RaycastHit objects.

Raycast(Vector3, Vector3, bool, float, int?)

Performs a raycast from the given origin and direction, returning the hits.

public IEnumerable<RaycastHit> Raycast(Vector3 origin, Vector3 direction, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
origin	Vector3	The starting point of the ray.
direction	Vector3	The direction of the ray.
sortByDistance	bool	If true, sorts hits by distance from the origin.
maxDistance	float	The maximum distance to cast the ray.
layerMask	int?	Optional layer mask to filter raycast hits.

Returns

IEnumerable<RaycastHit> — An enumerable of RaycastHit objects.

SphereCast(Vector3, float, Vector3, bool, float, int?)

Performs a sphere cast from the given origin with the specified radius and direction, returning the hits.

public IEnumerable<RaycastHit> SphereCast(Vector3 origin, float radius, Vector3 direction, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
origin	Vector3	The starting point of the sphere cast.
radius	float	The radius of the sphere cast.
direction	Vector3	The direction to cast the sphere.
sortByDistance	bool	If true, sorts hits by distance from the origin.
maxDistance	float	The maximum distance to cast the sphere.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<RaycastHit> — An enumerable of RaycastHit objects.

SphereCast(Ray, float, bool, float, int?)

Performs a sphere cast using the specified Ray and radius, returning the hits.

public IEnumerable<RaycastHit> SphereCast(Ray ray, float radius, bool sortByDistance = false, float maxDistance = Infinity, int? layerMask = null)

Parameters

Name	Type	Description
ray	Ray	The ray to cast the sphere along.
radius	float	The radius of the sphere cast.
sortByDistance	bool	If true, sorts hits by distance from the ray origin.
maxDistance	float	The maximum distance to cast the sphere.
layerMask	int?	Optional layer mask to filter hits.

Returns

IEnumerable<RaycastHit> — An enumerable of RaycastHit objects.