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←API Reference ←NSDK

PlaybackSession

↳ inherits from ARKit.ARSession

Declaration

class PlaybackSession

Summary

Drives playback. Subclasses ARSession so it can be assigned to ARView.session and the app can use the same delegate pattern. Runs a loop on a background queue, builds PlaybackFrame per frame from the PlaybackDataset, dispatches to the main queue, and notifies the delegate and PlaybackRenderer. Relation to Apple AR: Replaces the behavior of ARSession (no real device frames); API-compatible so ARView and delegate code don't need to know it's playback.

Constructors

init(dataset: PlaybackDataset)

Summary

Initializes a new playback session with an existing dataset.

Properties

Name	Type	Summary
var compassTimestampBase	ClockBase	Clock the played-back dataset's compass timestamps are on.
var currentPlaybackFrame	PlaybackFrame	The most recently delivered playback frame. Set on the main queue when each frame is delivered. Use this to get camera or frame data outside the delegate (e.g. in a render loop).
weak var playbackDelegate	( PlaybackSessionDelegate)?	Delegate that receives frame updates during playback
var playbackRenderer	PlaybackRenderer?	-

Methods

Name	Type	Summary
hasDepth	Bool	Returns whether the dataset contains LiDAR depth (depthSource == "lidar"). Used by NSDKView.hasDepth and feature checks.
override pause	void	Stops playback. The loop exits on its next iteration; the current frame index is preserved so a later `run()` resumes from the same frame.
override run	void	Starts playback. The playback loop runs asynchronously on a background queue; frames are delivered on the main queue. Configuration and options are ignored (playback uses the dataset's frame rate and content). Call `pause()` to stop.