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punktfunk/clients/apple
enricobuehler 76832a5b86
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fix(client/apple): two DualSenses stop fighting over one device, and a failed stop stops lying
Five faults in the Apple client's feedback path.

With two DualSenses attached, each pad's renderer opened "the first connected
DualSense" — taken from an unordered Set, so the choice could differ between
two calls in one process. Both renderers could land on the same device, one
pad's rumble coming out of the other while their per-instance write dedupes
fought over it, or they could split by luck. Each renderer now asks for the
device its own controller is, correlating GameController's stable ordering with
IOKit's location ids; the selection rule is a pure function so it can be tested
without an IOHIDDevice, which cannot be constructed. Without a preference the
lowest location id wins — still arbitrary, but stable, which Set.first was not.

A failed HID write was logged and swallowed, so a write that never reached the
device still counted as a successful render. That matters most for a stop,
which has nothing behind it: the renderer stamped its write clock even on
failure, the keepalive only re-writes non-zero levels, the ticker is cancelled
once the target is zero, and on USB there is no firmware timeout. A swallowed
stop therefore left the motors running with nothing scheduled to try again.
The write result now reaches the caller, which drops the handle and falls back
to CoreHaptics rather than claiming success.

A half-failed split-handle setup reported HEALTHY. Only the all-nil case
counted as failure, so one surviving handle passed silently while rendering
something wrong in a direction that depended on which handle died: lose the
right one and render falls to the combined branch, playing max(low, high) on
the LEFT handle; lose the left and the split branch discards the heavy motor
outright. A half-open split now tears the survivor down and takes the combined
path, which at least renders both motors somewhere.

Session end never put the lightbar out. This class is what turned it on, and
every DS write is valid-flag-selective, so a game's last colour stayed lit in
firmware after the stream ended — a DS4 was cleared incidentally because its
player indicator IS the lightbar, a DualSense was not.

And the renderer's stop() ran on the main actor. It is a queue.sync whose body
is a per-motor CHHapticEngine.stop() — an XPC round trip the renderer's own
notes record as able to hang — plus a blocking HID write to a device that has
just departed, and it queues behind any in-flight setup(). It runs on every
unplug and every pin change, and the main thread drives the presenter's
CADisplayLink, so it hitched the picture mid-stream. It is detached now; the
renderer is already off routing by then, so nothing observes it.

Verified: swift build clean, 188 tests pass (185 before), and the three new
device-selection tests fail if the deterministic fallback is reverted.

Note for anyone rebuilding here: the checked-in xcframework was stale (it
predates punktfunk_connection_report_phase) and build-xcframework.sh still dies
on this Mac at its macOS-floor guard. A macos-arm64 slice assembled by hand
from `cargo build --target aarch64-apple-darwin` is enough to typecheck.

From the 2026-08-03 force-feedback sweep (B14, B15, B18, B19, B20).
2026-08-04 08:20:12 +02:00
..

punktfunk — Apple client (macOS · iOS · iPadOS · tvOS)

The native Apple app for streaming a punktfunk host to your Mac, iPhone, iPad, or Apple TV. A SwiftUI app that finds hosts on your network, pairs with a PIN, and streams at your display's own resolution and refresh rate — with VideoToolbox hardware decode and full controller support.

All the networking and protocol work — QUIC control plane, UDP data plane, GF(2¹⁶) FEC, AES-GCM, Opus audio, cert pinning — lives in the shared Rust punktfunk-core (statically linked as PunktfunkCore.xcframework). This package is the Swift shell: decode, present, input, and UI.

Features

  • Hardware decode — VideoToolbox H.264/HEVC (plus AV1 on devices with an AV1 hardware decoder — M3-class Macs, A17 Pro-class iPhones), with a low-latency stage-2 presenter (VTDecompressionSessionCAMetalLayer, presented off a CADisplayLink, ~11 ms p50) as the default and an AVSampleBufferDisplayLayer fallback.
  • HDR & 4:4:4 — PQ passthrough with a correct reference-white anchor, mid-session SDR↔HDR reconfiguration, and hardware-probed 4:4:4 support.
  • Your display's native mode — the host builds a virtual output at exactly your WxH@Hz; mid-stream resize renegotiates without reconnecting.
  • Audio both ways — Opus playback (CoreAudio, no bundled libopus) with a jitter ring, plus mic uplink; speaker/mic selectable in Settings.
  • Full controller support — one selected controller forwarded as pad 0, including DualSense feedback (rumble → CoreHaptics, lightbar, player LEDs, adaptive triggers) and touchpad/motion. The virtual pad type auto-resolves from your physical controller.
  • Mouse & keyboardGCMouse/GCKeyboard capture with click-to-capture and a ⌃⌥⇧Q release (the cross-client Ctrl+Alt+Shift+Q; ⌘⎋ still works as the macOS/iPad toggle), plus iPad pointer lock and touch input.
  • Find hosts automatically — mDNS discovery (NWBrowser over _punktfunk._udp); first connect does a one-time SPAKE2 PIN pairing (or TOFU on trusted LANs), then reconnects on a pinned, Keychain-stored identity.
  • Tune the stream — a fps / Mb·s / latency HUD (skew-corrected across machines), a bitrate control, a per-host network speed test with a recommended bitrate, and a host-compositor picker.

Runs from one shared codebase across macOS, iOS, iPadOS, and tvOS.

Get it

Install from the App Store / TestFlight, or build from source below. Per-device install steps and the pairing walkthrough: docs.punktfunk.unom.io/docs/install-client.

Build / run / test (on a Mac)

Requires Xcode 26.5 / Swift 6.3. First build the Rust core into an xcframework, then build the app:

rustup target add aarch64-apple-darwin x86_64-apple-darwin
bash scripts/build-xcframework.sh            # → clients/apple/PunktfunkCore.xcframework
#   BUILD_IOS=1  also builds the iOS slices  (add the ios rustup targets)
#   BUILD_TVOS=1 also builds tvOS            (tier-3 targets, built from source — see below)

cd clients/apple
open Punktfunk.xcodeproj                      # the real app: ⌘R builds + runs Punktfunk.app
swift run PunktfunkClient                     # or the unbundled dev shell (CLI)
swift build && swift test                     # unit + loopback/remote tests (self-skip w/o a host)

tvOS slices are tier-3 Rust targets, built from source: rustup toolchain install nightly && rustup component add rust-src --toolchain nightly.

Test against a host

# full loopback proof — builds punktfunk-host (synthetic source, runs on macOS) and streams
# byte-verified frames into the Swift client, incl. the PIN pairing ceremony:
bash test-loopback.sh

# against a real Linux host on the LAN (see the repo README "Running on this box"):
PUNKTFUNK_REMOTE_HOST=<box-ip> swift test --filter RemoteFirstLightTests            # headless
PUNKTFUNK_AUTOCONNECT=<box-ip> PUNKTFUNK_MODE=1280x720x60 swift run PunktfunkClient # on glass

Project layout

  • PunktfunkKit (library) — the reusable pieces:
    • PunktfunkConnection — the wrapper over the C ABI (thread-safe close(), per-plane locks, pinning + TOFU).
    • AnnexB / StreamView / VideoDecoder / MetalVideoPresenter — format handling, the stage-1 (AVSampleBufferDisplayLayer) and stage-2 (VTDecompressionSessionCAMetalLayer) presenters.
    • InputCaptureGCMouse/GCKeyboard → host VK/mouse, with fractional-delta accumulation.
    • GamepadManager / GamepadCapture / GamepadFeedback / DualSenseTriggerEffect — controller discovery + selection, capture (buttons/axes/touchpad/motion), and host-feedback rendering.
    • HostDiscoveryNWBrowser over _punktfunk._udp.
  • PunktfunkClient (the app) — hosts grid with an On this network section, add-host sheet, the two trust flows (TOFU prompt + SPAKE2 PairSheet), the stream view with the HUD, a tabbed Settings pane (General / Display / Audio / Controllers / Advanced), and the network speed test. A Scene-level Stream menu carries the cross-client shortcut set: Release Mouse (⌃⌥⇧Q), Disconnect (⌃⌥⇧D) and the HUD toggle (⌃⌥⇧S) — the same Ctrl+Alt+Shift combos the Windows and Linux clients reserve, also shown on a 6-second banner at stream start. On iOS/iPadOS and macOS a connected controller swaps the whole home for the gamepad UI (Home/Gamepad*, Settings/GamepadSettingsView): a console-style host carousel (A connect · Y library · X settings), a controller-navigable settings screen, an add-host flow with an on-screen controller keyboard (no touch required anywhere), and the coverflow library browser — all driven by the shared GamepadMenuInput poller + GamepadCarousel/GamepadMenuList focus machinery, with dual-channel haptics (device Taptic + controller MenuHaptics), over an animated "aurora" backdrop (GamepadScreenBackground — TimelineView-driven drifting color blobs; deliberately pure SwiftUI, since a .metal library only reliably bundles in one of the two build systems these sources compile under). macOS presents the settings/add-host screens as sheets (no fullScreenCover there); PUNKTFUNK_FORCE_GAMEPAD_UI=1 forces the mode without a physical pad (dev/screenshots).
  • Tests (swift test) — Annex-B units, a real-codec VideoToolbox round trip, DualSense trigger-effect and gamepad-wire conversions, loopback integration against real local hosts, and the remote first-light test.

Notes for contributors

  • Xcode project (Punktfunk.xcodeproj) wraps the same sources as the swift run shell (a synchronized folder — no duplication). The macOS target is App-Sandboxed (needs network.server — the raw-UDP plane and quinn both bind()); iOS/tvOS use the shared entitlements file (keep app-sandbox out of it). Verify with codesign -d --entitlements :- <built .app>.
  • Decode flow: the host opens every stream with an IDR carrying VPS/SPS/PPS in-band, and recovery keyframes re-send them — refresh the format description on every IDR; there is no out-of-band extradata, ever.
  • ABI threading: one video pump thread per connection, one optional audio drain thread, and one optional feedback drain thread (rumble + HID-output). send() is enqueue-only and safe alongside all of them. The wrapper's per-plane locks make close() safe from anywhere.
  • DualSense motion scale (GamepadWire) is derived from hid-playstation's math, not yet live-verified — if gyro/accel feel wrong in a game, correct sign/scale there and evtest the host's virtual pad.
  • App Store screenshots are automated — tools/screenshots.sh all renders the real UI at the required pixel sizes via a DEBUG-only shot mode; the apple CI workflow captures the iOS sizes on every main push. See the script header for details.
  • Deeper design notes live in the internal planning repo (punktfunk-planning: apple-stage2-presenter.md).