# VolumetricProtocol A set of methods for working with Spatial primitives with volume. ``` protocol VolumetricProtocol : SpatialTypeProtocol ``` ## Topics ### Instance Properties [`var size: Self.Size`](/documentation/Spatial/VolumetricProtocol/size) The size of the volume. ### Instance Methods [`func contains(Self) -> Bool`](/documentation/Spatial/VolumetricProtocol/contains(_:)) Returns a Boolean value that indicates whether the entity contains the specified volumetric entity. [`func contains(anyOf: [Self.Point]) -> Bool`](/documentation/Spatial/VolumetricProtocol/contains(anyOf:)) Returns a Boolean value that indicates whether this volume contains any of the specified points. [`func contains(point: Self.Point) -> Bool`](/documentation/Spatial/VolumetricProtocol/contains(point:)) Returns a Boolean value that indicates whether this volume contains the specified point. [`func formIntersection(Self)`](/documentation/Spatial/VolumetricProtocol/formIntersection(_:)) Sets the primitive to the intersection of itself and the specified primitive. [`func formUnion(Self)`](/documentation/Spatial/VolumetricProtocol/formUnion(_:)) Sets the primitive to the union of itself and the specified primitive. [`func intersection(Self) -> Self?`](/documentation/Spatial/VolumetricProtocol/intersection(_:)) Returns the intersection of two volumetric entities. [`func union(Self) -> Self`](/documentation/Spatial/VolumetricProtocol/union(_:)) Returns the smallest volumetric entity that contains the two source entities. ## Relationships ### Inherits From [`Encodable`](/documentation/Swift/Encodable) [`Equatable`](/documentation/Swift/Equatable) [`Decodable`](/documentation/Swift/Decodable) [`SpatialTypeProtocol`](/documentation/Spatial/SpatialTypeProtocol) ### Conforming Types [`Size3DFloat`](/documentation/Spatial/Size3DFloat) [`Rect3D`](/documentation/Spatial/Rect3D) [`Size3D`](/documentation/Spatial/Size3D) [`Rect3DFloat`](/documentation/Spatial/Rect3DFloat) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)