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Physics.Raycast

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

Parameters

originThe starting point of the ray in world coordinates.
directionThe direction of the ray.
maxDistanceThe max distance the ray should check for collisions.
layerMaskA Layer mask that is used to selectively ignore Colliders when casting a ray.
queryTriggerInteractionSpecifies whether this query should hit Triggers.

Returns

bool True if the ray intersects with a Collider, otherwise false.

Description

Casts a ray, from point origin, in direction direction, of length maxDistance, against all colliders in the scene.

You may optionally provide a LayerMask, to filter out any Colliders you aren't interested in generating collisions with.

Specifying queryTriggerInteraction allows you to control whether or not Trigger colliders generate a hit, or whether to use the global Physics.queriesHitTriggers setting.

This example creates a simple Raycast, projecting forwards from the position of the object's current position, extending for 10 units.

using UnityEngine;

public class ExampleClass : MonoBehaviour { // C# example. void Update() { // Bit shift the index of the layer (8) to get a bit mask int layerMask = 1 << 8;

// This would cast rays only against colliders in layer 8. // But instead we want to collide against everything except layer 8. The ~ operator does this, it inverts a bitmask. layerMask = ~layerMask;

RaycastHit hit; // Does the ray intersect any objects excluding the player layer if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3.forward), out hit, Mathf.Infinity, layerMask)) { Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.forward) * hit.distance, Color.yellow); Debug.Log("Did Hit"); } else { Debug.DrawRay(transform.position, transform.TransformDirection(Vector3.forward) * 1000, Color.white); Debug.Log("Did not Hit"); } } }
using UnityEngine;

public class ExampleClass : MonoBehaviour { void FixedUpdate() { Vector3 fwd = transform.TransformDirection(Vector3.forward);

if (Physics.Raycast(transform.position, fwd, 10)) print("There is something in front of the object!"); } }

Notes: Raycasts will not detect Colliders for which the Raycast origin is inside the Collider.


public static bool Raycast(Vector3 origin, Vector3 direction, out RaycastHit hitInfo, float maxDistance, int layerMask, QueryTriggerInteraction queryTriggerInteraction);

Parameters

originThe starting point of the ray in world coordinates.
directionThe direction of the ray.
hitInfoIf true is returned, hitInfo will contain more information about where the collider was hit. (See Also: RaycastHit).
maxDistanceThe max distance the ray should check for collisions.
layerMaskA Layer mask that is used to selectively ignore colliders when casting a ray.
queryTriggerInteractionSpecifies whether this query should hit Triggers.

Returns

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

Description

Casts a ray against all colliders in the scene and returns detailed information on what was hit.

This example reports the distance between the current object and the reported Collider:

using UnityEngine;

public class RaycastExample : MonoBehaviour { void FixedUpdate() { RaycastHit hit;

if (Physics.Raycast(transform.position, -Vector3.up, out hit)) print("Found an object - distance: " + hit.distance); } }

This example re-introduces the maxDistance parameter to limit how far ahead to cast the Ray:

using UnityEngine;

public class RaycastExample : MonoBehaviour { void FixedUpdate() { RaycastHit hit;

if (Physics.Raycast(transform.position, -Vector3.up, out hit, 100.0f)) print("Found an object - distance: " + hit.distance); } }

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

Parameters

rayThe starting point and direction of the ray.
maxDistanceThe max distance the ray should check for collisions.
layerMaskA Layer mask that is used to selectively ignore colliders when casting a ray.
queryTriggerInteractionSpecifies whether this query should hit Triggers.

Returns

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

Description

Same as above using ray.origin and ray.direction instead of origin and direction.

using UnityEngine;

public class ExampleClass : MonoBehaviour { void Update() { Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition); if (Physics.Raycast(ray, 100)) print("Hit something!"); } }

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

Parameters

rayThe starting point and direction of the ray.
hitInfoIf true is returned, hitInfo will contain more information about where the collider was hit. (See Also: RaycastHit).
maxDistanceThe max distance the ray should check for collisions.
layerMaskA Layer mask that is used to selectively ignore colliders when casting a ray.
queryTriggerInteractionSpecifies whether this query should hit Triggers.

Returns

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

Description

Same as above using ray.origin and ray.direction instead of origin and direction.

This example draws a line along the length of the Ray whenever a collision is detected:

using UnityEngine;

public class ExampleClass : MonoBehaviour { void Update() { Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition); RaycastHit hit;

if (Physics.Raycast(ray, out hit, 100)) Debug.DrawLine(ray.origin, hit.point); } }

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