# Fx3DAPI_v5 An API that defines the methods the host application provides to get information about the 3D environment, including camera and object transforms. ``` protocol Fx3DAPI_v5 ``` ## Topics ### Accessing the 3D Environment [`func focalLength(at: CMTime, error: NSErrorPointer) -> Double`](/documentation/professional_video_applications/Fx3DAPI_v5/focalLength(at:error:)) Gets the focal length. [`func layerMatrix(at: CMTime) throws -> FxMatrix44`](/documentation/professional_video_applications/Fx3DAPI_v5/layerMatrix(at:)) Gets the 4x4 layer matrix, which is equivalent to the model matrix for the object that the effect is applied to. [`func viewMatrix(at: CMTime) throws -> FxMatrix44`](/documentation/professional_video_applications/Fx3DAPI_v5/viewMatrix(at:)) Gets the 4x4 view matrix. [`func metalProjectionMatrix(at: CMTime) throws -> FxMatrix44`](/documentation/professional_video_applications/Fx3DAPI_v5/metalProjectionMatrix(at:)) Gets the 4x4 Metal projection matrix. [`func frustumLeft(UnsafeMutablePointer!, right: UnsafeMutablePointer!, bottom: UnsafeMutablePointer!, top: UnsafeMutablePointer!, near: UnsafeMutablePointer!, far: UnsafeMutablePointer!, at: CMTime) throws`](/documentation/professional_video_applications/Fx3DAPI_v5/frustumLeft(_:right:bottom:top:near:far:at:)) Describes the bounds of the viewing solid for generating a projection matrix. --- 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)