# ComputeGraphViewpointComponent A transient component that provides camera viewpoint information to the particle simulation. ``` struct ComputeGraphViewpointComponent ``` ## Overview Attach this component to an entity to supply the simulation with an observer’s position and direction. The simulation uses these values for view-dependent effects such as billboard orientation or camera-facing particles. Both properties are optional. When `nil`, the simulation falls back to its default viewpoint behavior. ## Topics ### Initializers [`init()`](/documentation/RealityKit/ComputeGraphViewpointComponent/init()) ### Instance Properties [`var viewDirection: SIMD3?`](/documentation/RealityKit/ComputeGraphViewpointComponent/viewDirection) The direction the observer is facing, in world space. [`var viewPosition: SIMD3?`](/documentation/RealityKit/ComputeGraphViewpointComponent/viewPosition) The position of the observer, in world space. ## Relationships ### Conforms To [`TransientComponent`](/documentation/RealityKit/TransientComponent) [`Component`](/documentation/RealityKit/Component) --- 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)