# boundsMargin A margin applied to an entity’s bounding box that determines object visibility. ``` var boundsMargin: Float { get set } ``` ## Discussion When determining which entities are currently visible, RealityKit tests each entity’s bounding box to see if it overlaps with the camera’s field of view (also known as the camera’s *frustum*). For efficiency, entities with a bounding box that don’t overlap the camera’s frustum aren’t rendered. Use this property to prevent RealityKit from incorrectly culling entities that use a [`CustomMaterial`](/documentation/RealityKit/CustomMaterial) with a geometry modifier that moves vertices outside of the entity’s bounding box. RealityKit adds the value of `boundsMargin` to the bounding box before determining which entities are visible. > Note: On visionOS, if a mesh has an incorrect axis-aligned bounding > box (AABB), you might see pixelated passthrough artifacts on the mesh > due to inaccurate depth reprojection. Provide a correct AABB for your > virtual content, or if the mesh is animated by a shader, make the AABB > more conservative using this property. --- 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)