Unity Script Reference:

static function OverlapCircle(point: Vector2, radius: float, layerMask: int = DefaultRaycastLayers, minDepth: float = -Mathf.Infinity, maxDepth: float = Mathf.Infinity): Collider2D;

static Collider2D OverlapCircle(Vector2 point, float radius, int layerMask = DefaultRaycastLayers, float minDepth = -Mathf.Infinity, float maxDepth = Mathf.Infinity);

static def OverlapCircle(point as Vector2, radius as float, layerMask as int = DefaultRaycastLayers, minDepth as float = -Mathf.Infinity, maxDepth as float = Mathf.Infinity) as Collider2D

Parameters

point	Centre of the circle.
radius	Radius of the circle.
layerMask	Filter to check objects only on specific layers.
minDepth	Only include objects with a Z coordinate (depth) greater than this value.
maxDepth	Only include objects with a Z coordinate (depth) less than this value.

Description

Check if a collider falls within a circular area.

The circle is defined by its centre coordinate in world space and by its radius. The optional layerMask allows the test to check only for objects on specific layers.

Although the Z axis is not relevant for rendering or collisions in 2D, you can use the minDepth and maxDepth parameters to filter objects based on their Z coordinate. If more than one collider falls within the circle then the one returned will be the one with the lowest Z coordinate value. Null is returned if there are no colliders in the circle.

Note that this function will allocate memory for the returned Collider2D object. You can use OverlapCircleNonAlloc to avoid this overhead if you need to make the check frequently.