# boundingBox(atTime:) Returns the minimum region entirely enclosing the object’s contents at the specified time sample. ``` func boundingBox(atTime time: TimeInterval) -> MDLAxisAlignedBoundingBox ``` ## Parameters `time` A timestamp referring to timed information in the asset. ## Return Value The asset’s bounding box as of the specified time sample. ## Discussion Objects may or may not provide spatial content. Subclasses of [`MDLObject`](/documentation/ModelIO/MDLObject) that include spatial content, such as the [`MDLMesh`](/documentation/ModelIO/MDLMesh) class, implement this method to return the axis-aligned minimal region that entirely encloses such content. Objects without spatial content return an empty bounding box—that is, a [`MDLAxisAlignedBoundingBox`](/documentation/ModelIO/MDLAxisAlignedBoundingBox) structure whose `minBounds` field is greater than its `maxBounds` field. Calling this method on an object that contains other objects (that is, one whose [`children`](/documentation/ModelIO/MDLObject/children) property is not `nil` and references a nonempty container) recursively computes the combined bounding box enclosing of the object’s children. --- 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)