Playing and editing Cinematic mode video

At a glance

Project structure

Source bundle/
└── CinematicVideoPlaybackAndEditing/
    ├── CinematicVideoPlaybackAndEditingApp.swift
    ├── ContentView.swift
    ├── AssetView.swift
    ├── CinematicPlayer.swift
    ├── PlayerLayerView.swift
    ├── SampleCustomCompositor.swift
    ├── CinematicAssetReader.swift
    ├── CinematicAsset.swift
    ├── CinematicAssetData.swift
    ├── CinematicEditHelper.swift
    ├── CinematicEditor.swift
    └── PlayerLayerContainer.swift

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: Metal, Swift.
• The verified tree contains 4 project/configuration file(s) and 18 source declaration(s).

Overall architecture

flowchart LR
    N1["CinematicVideoPlaybackAndEditingApp"]
    N2["ContentView"]
    N3["CinematicPlayer"]
    N4["Cinematic APIs"]
    N1 --> N2
    N2 --> N3
    N3 --> N4

Reference code

CinematicVideoPlaybackAndEditing/CinematicVideoPlaybackAndEditingApp.swift:10 — architecture anchor

@main
struct CinematicVideoPlaybackAndEditingApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

Interpretation

The arrows summarize the source-visible entry, role-named types or folders, and framework direction; when nodes come from structural folders, the sequence is a high-level interpretation rather than proof that every adjacent node calls the next. Ownership is claimed only where the next section cites a stored property or assignment. The diagram is intentionally limited to the dominant path into Cinematic.

Ownership and state

classDiagram
    ContentView *-- PhotosPickerItem : selectedPickerItem
    ContentView *-- CinematicAsset : selectedAsset
    ContentView *-- AsyncStream : continuation
    AssetView o-- CinematicAsset : asset

Ownership evidence

CinematicVideoPlaybackAndEditing/ContentView.swift:13 — stored dependency or nearest verified ownership anchor

struct ContentView: View {
    // ...
    @State private var selectedPickerItem: PhotosPickerItem?
    // ...
}

Composition arrows indicate a source-visible construction expression or locally owned value state; aggregation means the owner stores or receives a dependency without proving exclusive lifetime ownership.

Class and protocol design

CinematicVideoPlaybackAndEditing/ViewRepresentable.swift:21 — representative type boundary

public protocol ViewRepresentable: PlatformViewRepresentable {
    // ...
}

The source explicitly defines local protocol relationships: PlayerLayerContainer → ViewRepresentable.

Access control

Reference code

CinematicVideoPlaybackAndEditing/CinematicEditHelper.swift:54 — representative boundary

    private func texture(from outputBuffer: CVPixelBuffer) -> MTLTexture? {
        // ...
    }

Swift declarations without a modifier are internal; explicit private, fileprivate, private(set), public, or open entries above are interpreted by language semantics. Objective-C/C samples instead rely on header and implementation boundaries, which are not equivalent to Swift lexical privacy.

Logic ownership and placement

Design patterns

Naming conventions

• Types: App: CinematicVideoPlaybackAndEditingApp; Player: CinematicPlayer; View: AssetView, ContentView, PlayerLayerView.
• Protocols: ViewRepresentable.
• Methods: refreshPlayer, setVideoComposition, refreshFrame, renderContextChanged, startRequest, drawFocusDetections, setupForReading, cancelReading.
• Files: CinematicVideoPlaybackAndEditing/CinematicVideoPlaybackAndEditingApp.swift, CinematicVideoPlaybackAndEditing/ContentView.swift, CinematicVideoPlaybackAndEditing/AssetView.swift, CinematicVideoPlaybackAndEditing/CinematicPlayer.swift, CinematicVideoPlaybackAndEditing/PlayerLayerView.swift, CinematicVideoPlaybackAndEditing/SampleCustomCompositor.swift.

Architecture takeaways

• CinematicVideoPlaybackAndEditingApp is the main source-visible entry or composition anchor for this sample.
• Framework work reaches AVFoundation, SwiftUI, Cinematic, CoreMedia through a deliberately small high-level chain; the detailed API graph remains inside the cited implementation files.
• Stored-property evidence identifies lifecycle collaboration; it does not by itself prove exclusive object ownership.
• Access-control conclusions separate verified language visibility from the likely design rationale.
• Local protocol relationships provide an explicit substitution boundary.

Source map

• Official Apple documentation