| Parameter | Description |
|---|---|
| ray | The starting point and direction of the ray. |
| results | The buffer to store the hits into. |
| maxDistance | The max distance the rayhit is allowed to be from the start of the ray. |
| layerMask | A Layer mask that is used to selectively filter which colliders are considered when casting a ray. |
| queryTriggerInteraction | Specifies whether this query should hit Triggers. |
int
The amount of hits stored into the results buffer.
Cast a ray through the Scene and store the hits into the buffer.
Like Physics.RaycastAll, but generates no garbage.
The raycast query ends when there are no more hits and/or the results buffer is full. The order of the results is undefined. When a full buffer is returned it is not guaranteed that the results are the closest hits and the length of the buffer is returned. If a null buffer is passed in, no results are returned and no errors or exceptions are thrown.
| Parameter | Description |
|---|---|
| origin | The starting point and direction of the ray. |
| results | The buffer to store the hits into. |
| direction | The direction of the ray. |
| maxDistance | The max distance the rayhit is allowed to be from the start of the ray. |
| queryTriggerInteraction | Specifies whether this query should hit Triggers. |
| layerMask | A Layer mask that is used to selectively filter which colliders are considered when casting a ray. |
int
The amount of hits stored into the results buffer.
Cast a ray through the Scene and store the hits into the buffer.
using UnityEngine;
public class RaycastFanNonAlloc : MonoBehaviour { public int rayCount = 10; // Number of rays in the fan public float angle = 60f; // Total spread angle in degrees public float maxDistance = 20f; // Ray length // The size of the array determines how many raycasts will occur RaycastHit[] m_Results = new RaycastHit[5]; // Reused buffer to avoid GC allocations
// See Order of Execution for Event Functions for information on FixedUpdate() and Update() related to physics queries void FixedUpdate() { Vector3 origin = transform.position; Vector3 forward = transform.forward; float halfAngle = angle / 2f;
for (int i = 0; i < rayCount; i++) { // Interpolate angle across the spread range float lerp = (float)i / (rayCount - 1); float currentAngle = Mathf.Lerp(-halfAngle, halfAngle, lerp);
// Rotate direction around Y axis Quaternion rotation = Quaternion.AngleAxis(currentAngle, Vector3.up); Vector3 direction = rotation * forward;
// Note: The buffer is overwritten from index 0 up to the number of hits returned. Unused slots remain unchanged. int hits = Physics.RaycastNonAlloc(origin, direction, m_Results, maxDistance);
if (hits > 0) { for (int j = 0; j < hits; j++) { Debug.Log($"Ray {i} hit {m_Results[j].collider.gameObject.name}"); Debug.DrawLine(origin, m_Results[j].point, Color.green); } } else { Debug.DrawRay(origin, direction * maxDistance, Color.red); } } } }