ARKit iOS 11.2 to 11.3 API Differences

ARAnchor.h
Modified ARAnchor
Protocols
FromNSCopying
ToNSCopying, NSSecureCoding

ARCamera.h
Added ARTrackingStateReasonRelocalizing
ARConfiguration.h
Added ARPlaneDetectionVertical
Added ARConfiguration.supportedVideoFormats
Added ARConfiguration.videoFormat
Added ARWorldTrackingConfiguration.autoFocusEnabled
Added ARWorldTrackingConfiguration.detectionImages
Added AROrientationTrackingConfiguration.autoFocusEnabled
ARError.h
Added ARErrorCodeInvalidReferenceImage
ARFaceGeometry.h
Modified ARFaceGeometry
Protocols
FromNSCopying
ToNSCopying, NSSecureCoding

ARHitTestResult.h
Added ARHitTestResultTypeEstimatedVerticalPlane
Added ARHitTestResultTypeExistingPlaneUsingGeometry
ARImageAnchor.h
Added ARImageAnchor
Added ARImageAnchor.referenceImage
ARPlaneAnchor.h
Added ARPlaneAnchorAlignmentVertical
Added ARPlaneAnchor.geometry
ARPlaneGeometry.h
Added ARPlaneGeometry
Added ARPlaneGeometry.vertexCount
Added ARPlaneGeometry.vertices
Added ARPlaneGeometry.textureCoordinateCount
Added ARPlaneGeometry.textureCoordinates
Added ARPlaneGeometry.triangleCount
Added ARPlaneGeometry.triangleIndices
Added ARPlaneGeometry.boundaryVertexCount
Added ARPlaneGeometry.boundaryVertices
Added ARSCNPlaneGeometry
Added +[ARSCNPlaneGeometry planeGeometryWithDevice:]
Added -[ARSCNPlaneGeometry updateFromPlaneGeometry:]
ARPointCloud.h
Modified ARPointCloud
Protocols
Fromnone
ToNSSecureCoding

ARReferenceImage.h
Added ARReferenceImage
Added ARReferenceImage.name
Added ARReferenceImage.physicalSize
Added -[ARReferenceImage initWithCGImage:orientation:physicalWidth:]
Added -[ARReferenceImage initWithPixelBuffer:orientation:physicalWidth:]
Added +[ARReferenceImage referenceImagesInGroupNamed:bundle:]
ARSession.h
Added -[ARSession setWorldOrigin:]
Added -[ARSessionObserver sessionShouldAttemptRelocalization:]
ARVideoFormat.h
Added ARVideoFormat
Added ARVideoFormat.imageResolution
Added ARVideoFormat.framesPerSecond