Version: 2022.3
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PhysicsScene2D.Raycast

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Declaration

public RaycastHit2D Raycast(Vector2 origin, Vector2 direction, float distance, int layerMask = Physics2D.DefaultRaycastLayers);

Declaration

public RaycastHit2D Raycast(Vector2 origin, Vector2 direction, float distance, ContactFilter2D contactFilter);

Parameters

origin The point in 2D space where the ray originates.
direction The vector representing the direction of the ray.
distance Maximum distance over which to cast the ray.
layerMask The filter used to detect Colliders only on certain layers.
contactFilter The contact filter used to filter the results differently, such as by layer mask and Z depth, or normal angle.

Returns

RaycastHit2D The cast results returned.

Description

Casts a ray against colliders in the PhysicsScene2D, returning the first intersection only.

A raycast is conceptually like a laser beam that is fired from a point in space along a particular direction. Any object making contact with the beam can be detected and reported. Raycasts are useful for determining lines of sight, targets hit by gunfire and for many other purposes in gameplay.

This function returns a RaycastHit2D object with a reference to the Collider2D that is hit by the ray (the collider property of the result will be NULL if nothing was hit).

The layerMask can be used to detect objects selectively only on certain layers (this allows you to apply the detection only to enemy characters, for example). Overloads of this method that use contactFilter can filter the results by the options available in ContactFilter2D.

Additionally, this will also detect collider(s) at the start of the ray. In this case, the ray starts inside the collider and doesn't intersect the collider surface. This means that the collision normal cannot be calculated, in which case the returned collision normal is set to the inverse of the ray vector being tested. This can easily be detected because such results are always at a RaycastHit2D fraction of zero.

Additional resources: PhysicsScene2D, RaycastHit2D, LayerMask, Physics2D.DefaultRaycastLayers, Physics2D.IgnoreRaycastLayer, Physics2D.queriesHitTriggers & Collider2D.Raycast.


Declaration

public int Raycast(Vector2 origin, Vector2 direction, float distance, RaycastHit2D[] results, int layerMask = Physics2D.DefaultRaycastLayers);

Declaration

public int Raycast(Vector2 origin, Vector2 direction, float distance, ContactFilter2D contactFilter, RaycastHit2D[] results);

Parameters

origin The point in 2D space where the ray originates.
direction The vector representing the direction of the ray.
distance Maximum distance over which to cast the ray.
layerMask The filter used to detect Colliders only on certain layers.
contactFilter The contact filter used to filter the results differently, such as by layer mask and Z depth, or normal angle.
results The array to receive results. The size of the array determines the maximum number of results that can be returned.

Returns

int Returns the number of results placed in the results array.

Description

Casts a ray against colliders the PhysicsScene2D, returning all intersections.

A raycast is conceptually like a laser beam that is fired from a point in space along a particular direction. Any object making contact with the beam can be detected and reported. Raycasts are useful for determining lines of sight, targets hit by gunfire and for many other purposes in gameplay.

This function returns any Collider2D that intersect the ray with the results returned in the supplied array. The integer return value is the number of objects that intersect the line (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. Note that you will always get zero results if you pass an empty array.

The layerMask can be used to detect objects selectively only on certain layers (this allows you to apply the detection only to enemy characters, for example). Overloads of this method that use contactFilter can filter the results by the options available in ContactFilter2D.

Additionally, this will also detect collider(s) at the start of the ray. In this case, the ray starts inside the collider and doesn't intersect the collider surface. This means that the collision normal cannot be calculated, in which case the returned collision normal is set to the inverse of the ray vector being tested. This can easily be detected because such results are always at a RaycastHit2D fraction of zero.

All results are sorted by ascending distance order.

Additional resources: PhysicsScene2D, RaycastHit2D, LayerMask, Physics2D.DefaultRaycastLayers, Physics2D.IgnoreRaycastLayer, Physics2D.queriesHitTriggers & Collider2D.Raycast.


Declaration

public int Raycast(Vector2 origin, Vector2 direction, float distance, ContactFilter2D contactFilter, List<RaycastHit2D> results);

Parameters

origin The point in 2D space where the ray originates.
direction The vector representing the direction of the ray.
distance Maximum distance over which to cast the ray.
contactFilter The contact filter used to filter the results differently, such as by layer mask and Z depth, or normal angle.
results The list to receive results.

Returns

int Returns the number of results placed in the results list.

Description

Casts a ray against Colliders the PhysicsScene2D, returning all intersections.

A raycast is conceptually like a laser beam that is fired from a point in space along a particular direction. Any object making contact with the beam can be detected and reported. Raycasts are useful for determining lines of sight, targets hit by gunfire and for many other purposes in gameplay.

The integer return value is the number of results written into the results list. The results list will be resized if it doesn't contain enough elements to report all the results. This prevents memory from being allocated for results when the results list does not need to be resized, and improves garbage collection performance when the query is performed frequently.

The results can also be filtered by the contactFilter. All results are sorted by ascending distance order.

Additional resources: PhysicsScene2D and RaycastHit2D.

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