Struct AABB3D

Axis-aligned 3D bounding box represented as Center + HalfExtents. The canonical Scylla type for shape bounds, frustum culling, spatial queries, and any "box that sits on world axes" use case.

Implements

IEquatable<AABB3D>

Inherited Members

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: Scylla.Core.Util.Geom

Assembly: ScyllaCore.dll

Syntax

[Serializable]
public struct AABB3D : IEquatable<AABB3D>

Remarks

Center + HalfExtents is preferred over Min + Max because it keeps Encapsulate(Vector3) / Expand(float) cheap and matches the layout of UnityEngine.Bounds. Implicit conversions to and from UnityEngine.Bounds are provided so callers can use either type freely.

HalfExtents components are expected to be non-negative. Behaviour with negative half-extents is undefined for intersection and containment queries.

Equality comparisons use Approximately(float, float, float) for each component, so two boxes that differ only by floating-point rounding will be considered equal.

For Burst-compatible AABB usage inside spatial data structures such as ScyllaBVH and ScyllaLooseOctreeCore, use ScyllaAABB3 from the Scylla.Core.Structures namespace instead.

Constructors

AABB3D(Vector3, Vector3)

Initializes a new AABB3D with the supplied center and half-extents.

Declaration

public AABB3D(Vector3 center, Vector3 halfExtents)

Parameters

Type	Name	Description
Vector3	center	The box center in world (or local) space.
Vector3	halfExtents	Half the box extent on each axis. Each component should be non-negative; negative values produce undefined results in intersection and containment queries.

Fields

Center

Center of the box expressed in the same coordinate space the box is defined in (typically world space).

Declaration

[SerializeField]
public Vector3 Center

Field Value

Type	Description
Vector3

Empty

A zero-size box centered at the world origin. Useful as a default or "uninitialized" sentinel value.

Declaration

public static readonly AABB3D Empty

Field Value

Type	Description
AABB3D

HalfExtents

Half the box's full extent on each axis. Each component should be non-negative. The relationship to the full size is Size = HalfExtents * 2.

Declaration

[SerializeField]
public Vector3 HalfExtents

Field Value

Type	Description
Vector3

Properties

Max

The maximum (most-positive) corner of the box, computed as Center + HalfExtents.

Declaration

public readonly Vector3 Max { get; }

Property Value

Type	Description
Vector3

Min

The minimum (most-negative) corner of the box, computed as Center - HalfExtents.

Declaration

public readonly Vector3 Min { get; }

Property Value

Type	Description
Vector3

Size

The full size of the box on each axis, equal to HalfExtents * 2. Each component corresponds to the box's extent along that world axis.

Declaration

public readonly Vector3 Size { get; }

Property Value

Type	Description
Vector3

SurfaceArea

The total surface area of the box, in square units. Computed as 2 * (wh + hd + d*w) where w, h, and d are the box's width, height, and depth respectively.

Declaration

public readonly float SurfaceArea { get; }

Property Value

Type	Description
float

Volume

The total volume enclosed by the box, in cubic units. Equals Size.x * Size.y * Size.z. Returns zero for a degenerate (flat or point) box.

Declaration

public readonly float Volume { get; }

Property Value

Type	Description
float

Methods

ClosestPoint(Vector3)

Returns the closest point on or inside the box to point. If point is already inside the box, it is returned unchanged.

Declaration

public readonly Vector3 ClosestPoint(Vector3 point)

Parameters

Type	Name	Description
Vector3	point	The query point in world space.

Returns

Type	Description
Vector3	The point within or on the surface of the box that is nearest to `point`. This is obtained by clamping `point` component-wise to the box's Min / Max range.

Contains(in AABB3D)

Returns true if other is fully contained within this box, meaning all eight corners of other lie inside or on the boundary of this box.

Declaration

public bool Contains(in AABB3D other)

Parameters

Type	Name	Description
AABB3D	other	The box to test for containment.

Returns

Type	Description
bool	`true` if `other` is entirely enclosed by this box; `false` if any part of `other` extends outside.

Contains(Vector3)

Returns true if point is inside or exactly on the boundary of this box.

Declaration

public bool Contains(Vector3 point)

Parameters

Type	Name	Description
Vector3	point	The world-space point to test.

Returns

Type	Description
bool	`true` if the point lies within the closed volume of the box (boundary contact counts as inside); `false` otherwise.

Distance(Vector3)

Returns the Euclidean distance from point to the nearest surface point of the box. Returns zero if point is inside or on the boundary of the box.

Declaration

public readonly float Distance(Vector3 point)

Parameters

Type	Name	Description
Vector3	point	The query point in world space.

Returns

Type	Description
float	A non-negative distance in world units. Zero means the point is inside or touching the box.

Encapsulate(in AABB3D)

Grows this box minimally to fully include other. Equivalent to calling Encapsulate(Vector3) for other's Min and Max corners. This method mutates the box in place.

Declaration

public void Encapsulate(in AABB3D other)

Parameters

Type	Name	Description
AABB3D	other	The box to include in this box.

Encapsulate(Vector3)

Grows this box minimally to include point. If the point is already inside, the box is unchanged. This method mutates the box in place.

Declaration

public void Encapsulate(Vector3 point)

Parameters

Type	Name	Description
Vector3	point	The world-space point to include in the box.

Equals(AABB3D)

Returns true if this box and other are approximately equal, comparing each component of Center and HalfExtents using Approximately(float, float, float).

Declaration

public bool Equals(AABB3D other)

Parameters

Type	Name	Description
AABB3D	other	The box to compare against.

Returns

Type	Description
bool	`true` if all six float components are within EPSILON of each other; `false` otherwise.

Equals(object)

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
object	obj

Returns

Type	Description
bool

Overrides

ValueType.Equals(object)

Expand(float)

Expands each half-extent by amount uniformly along all three axes. Use a negative value to shrink the box. This method mutates the box in place.

Declaration

public void Expand(float amount)

Parameters

Type	Name	Description
float	amount	The amount to add to each half-extent component. A positive value grows the box; a negative value shrinks it. Shrinking below zero produces negative half-extents, which are undefined for intersection queries.

Expand(Vector3)

Expands each half-extent by the corresponding component of amount, allowing per-axis control. This method mutates the box in place.

Declaration

public void Expand(Vector3 amount)

Parameters

Type	Name	Description
Vector3	amount	Per-axis expansion amounts. A positive component grows the box on that axis; a negative component shrinks it.

FromCenterSize(Vector3, Vector3)

Builds a new AABB3D from a center and a full-size vector. The half-extents are set to size * 0.5, matching the UnityEngine.Bounds constructor convention.

Declaration

public static AABB3D FromCenterSize(Vector3 center, Vector3 size)

Parameters

Type	Name	Description
Vector3	center	The center of the desired box.
Vector3	size	The full size of the box along each axis.

Returns

Type	Description
AABB3D	A new AABB3D centered at `center` with the given size.

FromMinMax(Vector3, Vector3)

Builds a new AABB3D from a minimum and maximum corner pair. The resulting box's center is the midpoint of min and max, and the half-extents are half the diagonal.

Declaration

public static AABB3D FromMinMax(Vector3 min, Vector3 max)

Parameters

Type	Name	Description
Vector3	min	The minimum (most-negative) corner of the desired box.
Vector3	max	The maximum (most-positive) corner of the desired box.

Returns

Type	Description
AABB3D	A new AABB3D that exactly spans the given corners.

FromPoints(ReadOnlySpan<Vector3>)

Builds the smallest axis-aligned box that contains all points in points. Returns Empty when the span is empty.

Declaration

public static AABB3D FromPoints(ReadOnlySpan<Vector3> points)

Parameters

Type	Name	Description
ReadOnlySpan<Vector3>	points	A read-only span of points to enclose. May be empty, in which case Empty is returned.

Returns

Type	Description
AABB3D	The tightest AABB3D enclosing all supplied points, or Empty if `points` contains no elements.

Remarks

The implementation performs a single linear scan, updating per-axis min/max values, so the time complexity is O(n) with no heap allocation.

GetCorner(int)

Returns one of the eight corner points of this box. The index parameter is bit-packed: bit 0 selects the maximum X face (versus minimum), bit 1 selects the maximum Y face, and bit 2 selects the maximum Z face. Valid indices are in the range [0, 7].

Declaration

public Vector3 GetCorner(int index)

Parameters

Type	Name	Description
int	index	A value from 0 to 7 that bit-encodes which corner to retrieve. Bit 0: X axis (0 = min, 1 = max). Bit 1: Y axis (0 = min, 1 = max). Bit 2: Z axis (0 = min, 1 = max).

Returns

Type	Description
Vector3	The world-space position of the selected corner.

Remarks

Iterating from index 0 to 7 visits all eight corners in a consistent, deterministic order. This is useful for computing conservative screen-space bounds or for feeding the eight corners into ToAABB3D().

GetHashCode()

Declaration

public override int GetHashCode()

Returns

Type	Description
int

Overrides

ValueType.GetHashCode()

Intersects(in AABB3D)

Returns true if this box and other overlap. Boundary contact (touching faces, edges, or corners) counts as an intersection.

Declaration

public bool Intersects(in AABB3D other)

Parameters

Type	Name	Description
AABB3D	other	The box to test against.

Returns

Type	Description
bool	`true` if the two boxes share any volume or surface point; `false` if they are completely separated.

Remarks

The test is a simple per-axis overlap check on the center-distance versus the sum of half-extents, equivalent to a degenerate Separating Axis Theorem test with three axes. It runs in constant time with no allocation.

IntersectsRay(Ray, out float)

Tests whether a ray intersects this box using the slab method. When the ray hits, distance receives the parametric distance along the ray to the first intersection point. If the ray origin is already inside the box, the distance is set to zero.

Declaration

public bool IntersectsRay(Ray ray, out float distance)

Parameters

Type	Name	Description
Ray	ray	The ray to test. The direction should be normalized for `distance` to correspond to world-space units, but need not be for a pure hit/miss test.
float	distance	When this method returns `true`, this parameter contains the distance along the ray to the entry point (zero if the origin is inside the box). The value is undefined when the method returns `false`.

Returns

Type	Description
bool	`true` if the ray intersects the box; `false` if the ray misses entirely (including rays that point away from the box from outside).

Remarks

Uses the slab method: for each axis the ray is intersected against the two parallel planes that bound the box on that axis. The resulting per-axis entry and exit intervals are intersected to determine overall overlap. Rays parallel to an axis are handled separately to avoid division by near-zero.

This test does not detect back-face intersections from inside the box; the returned distance is always non-negative.

ToString()

Returns a human-readable string representation of this box in the format AABB3D[Center=(x,y,z), HalfExtents=(x,y,z)].

Declaration

public override string ToString()

Returns

Type	Description
string	A formatted string describing the box's center and half-extents.

Overrides

ValueType.ToString()

Operators

operator ==(AABB3D, AABB3D)

Approximate equality operator. Delegates to Equals(AABB3D); two boxes that differ only by floating-point rounding are considered equal.

Declaration

public static bool operator ==(AABB3D left, AABB3D right)

Parameters

Type	Name	Description
AABB3D	left	The left operand.
AABB3D	right	The right operand.

Returns

Type	Description
bool	`true` if the boxes are approximately equal; `false` otherwise.

implicit operator Bounds(AABB3D)

Implicitly converts an AABB3D to a UnityEngine.Bounds value. The resulting Bounds has the same center and size.

Declaration

public static implicit operator Bounds(AABB3D box)

Parameters

Type	Name	Description
AABB3D	box	The source AABB3D to convert.

Returns

Type	Description
Bounds	A UnityEngine.Bounds with `center` equal to Center and `size` equal to Size.

implicit operator AABB3D(Bounds)

Implicitly converts a UnityEngine.Bounds to an AABB3D. The Bounds.extents field (which equals half the size) is used directly as HalfExtents.

Declaration

public static implicit operator AABB3D(Bounds bounds)

Parameters

Type	Name	Description
Bounds	bounds	The source UnityEngine.Bounds to convert.

Returns

Type	Description
AABB3D	An AABB3D with Center equal to `bounds.center` and HalfExtents equal to `bounds.extents`.

operator !=(AABB3D, AABB3D)

Approximate inequality operator. Returns the negation of operator ==(AABB3D, AABB3D).

Declaration

public static bool operator !=(AABB3D left, AABB3D right)

Parameters

Type	Name	Description
AABB3D	left	The left operand.
AABB3D	right	The right operand.

Returns

Type	Description
bool	`true` if the boxes are not approximately equal; `false` otherwise.

Implements

IEquatable<T>