Version: 2019.1 (switch to 2018.3 or 2017.4)
LanguageEnglish
  • C#

Collider2D.Cast

Suggest a change

Success!

Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.

Close

Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.

Close

Cancel

public int Cast(Vector2 direction, RaycastHit2D[] results, float distance = Mathf.Infinity, bool ignoreSiblingColliders = true);

Parameters

directionVector representing the direction to cast the shape.
resultsArray to receive results.
distanceMaximum distance over which to cast the shape.
ignoreSiblingCollidersDetermines whether the cast should ignore Colliders attached to the same Rigidbody2D (known as sibling Colliders).

Returns

int The number of results returned.

Description

Casts the Collider shape into the Scene starting at the Collider position ignoring the Collider itself.

This function will take the collider shape and cast it into the Scene starting at the collider position in the specified direction for an optional distance and return the results in the provided results array. The integer return value is the number of results written into the results array. 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 casts are performed frequently.

Additionally, this will also detect other Collider(s) at the collider start position if they are overlapping. In this case the cast shape will be starting inside the Collider and may not intersect the Collider surface. This means that the collision normal cannot be calculated in which case the collision normal returned is set to the inverse of the direction vector being tested.

Note: Use of Collider2D.Cast() requires the use of Rigidbody2D. If no Rigidbody2D is declared Cast() does not work. However a Rigidbody2D can be static and attached to the Collider2D. This will make the Cast() work as expected. Also, if the Collider2D object has no Rigidbody2D object then it can collide with objects which have both Collider2D and Rigidbody2D objects.


public int Cast(Vector2 direction, ContactFilter2D contactFilter, RaycastHit2D[] results, float distance = Mathf.Infinity, bool ignoreSiblingColliders = true);

Parameters

directionVector representing the direction to cast the shape.
contactFilterFilter results defined by the contact filter.
resultsArray to receive results.
distanceMaximum distance over which to cast the shape.
ignoreSiblingCollidersDetermines whether the cast should ignore Colliders attached to the same Rigidbody2D (known as sibling Colliders).

Returns

int The number of results returned.

Description

Casts the Collider shape into the Scene starting at the Collider position ignoring the Collider itself.

This function will take the collider shape and cast it into the Scene starting at the collider position in the specified direction for an optional distance and return the results in the provided results array. The integer return value is the number of results written into the results array. 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 casts are performed frequently.

The contactFilter parameter can filter the returned results by the options in ContactFilter2D.

Additionally, this will also detect other Collider(s) at the collider start position if they are overlapping. In this case the cast shape will be starting inside the Collider and may not intersect the Collider surface. This means that the collision normal cannot be calculated in which case the collision normal returned is set to the inverse of the direction vector being tested.


public int Cast(Vector2 direction, ContactFilter2D contactFilter, List<RaycastHit2D> results, float distance = Mathf.Infinity, bool ignoreSiblingColliders = true);

Parameters

directionVector representing the direction to cast the shape.
contactFilterFilter results defined by the contact filter.
resultsList to receive results.
distanceMaximum distance over which to cast the shape.
ignoreSiblingCollidersDetermines whether the cast should ignore Colliders attached to the same Rigidbody2D (known as sibling Colliders).

Returns

int The number of results returned.

Description

Casts the Collider shape into the Scene starting at the Collider position ignoring the Collider itself.

This function will take the Collider shape and cast it into the Scene starting at the Collider position in the specified direction for an optional distance and return the results in the provided results list. 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 casts are performed frequently.

The contactFilter parameter can filter the returned results by the options in ContactFilter2D.

Additionally, this also detects other Collider(s) at the Collider start position if they are overlapping. In this case, the cast shape will start inside the Collider and may not 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 direction vector being tested.

Did you find this page useful? Please give it a rating: