Files
punktfunk/clients/linux
enricobuehlerandClaude Opus 5 b297542c4d feat(clients/input): controllers can stop being forwarded, for couches that hand the pad over another way
A controller that reaches the host by USB passthrough — VirtualHere and friends, or simply a
pad plugged into the host — arrived there twice: once as the real device, once as the virtual
pad this client built from the same hands. Games read both, so a stick drifts against the
centred second pad and menus take every input twice.

New per-client setting, "Forward controllers", default on (today's behaviour). It is tier-P,
so a profile can decline what another profile forwards.

On Linux and Windows it is deliberately stronger than "send nothing". Opening a controller is
what CLAIMS it — SDL's HIDAPI drivers take the device node — and a claimed device is one a
passthrough tool cannot bind, so with this off the session opens no slot at all and never
enables the Valve HIDAPI drivers. Menu navigation is untouched: the launcher still opens the
active pad, and a session supersedes menu mode whether it forwards or not, so the pad is free
for the whole time a stream is up. The consequence, documented at both the setting and the
chord: the controller escape chord is read off forwarded pads, so it is unavailable there.

The Apple and Android input stacks claim nothing, so those clients keep their slots and their
chords and only gate the wire sends — losing tvOS's only controller way out of a stream would
have been the worse bug. Android does stop its DualSense and Steam Controller 2 USB captures,
which do claim the device.

Surfaces: GTK, WinUI, the console settings screen, Apple's touch and gamepad settings, the
Android touch and gamepad settings, and Decky (which also hides the rows that now have nothing
to act on). Everywhere the "which pad" and "pad type" rows grey out while it is off.

Verified: cargo clippy --all-targets -D warnings + 79 tests on pf-client-core, pf-console-ui,
punktfunk-client-session and punktfunk-client-linux (linux/amd64 container, gate proven
non-vacuous with a planted error); swift build for the Apple clients; gradle compile + 49 unit
tests for Android (likewise proven); tsc for Decky. clients/windows is UNCOMPILED — both
Windows boxes were offline; its edits were reviewed against the helper signatures by hand.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-02 22:21:26 +02:00
..

punktfunk — Linux client

The native Linux app for streaming a punktfunk host to your desktop, laptop, or Steam Deck. It's a clean relm4/GTK4/libadwaita shell that finds hosts on your network, pairs with a PIN, and manages your settings and library — the stream itself runs in the sibling punktfunk-session Vulkan binary (clients/session), which the shell spawns, putting the picture on glass at your display's own resolution and refresh rate.

Built in Rust end to end (no C ABI): the shell shares its plumbing with the session binary through crates/pf-client-core, which links the punktfunk-core protocol crate and speaks the fast punktfunk/1 protocol — QUIC control plane, GF(2¹⁶) FEC + AES-GCM data plane.

Features

  • Zero-copy hardware decode — the session presenter decodes via Vulkan Video on every GPU vendor (including NVIDIA), falling back to FFmpeg VAAPI → DRM-PRIME dmabuf and then software when Vulkan Video is unavailable.
  • Your display's native mode — the host builds a virtual output at exactly your WxH@Hz; no scaling, no letterboxing. Steady 60 fps at 1080p60, ~6 ms capture→decoded on the LAN.
  • Audio both ways — PipeWire playback with a jitter ring, plus mic uplink to the host.
  • Full controller support — SDL3 gamepads with rumble and DualSense fidelity (lightbar, player LEDs, touchpad, motion, adaptive-trigger replay). Click-to-capture keyboard and mouse, with a release chord (Ctrl+Alt+Shift+Q) and focus-loss release.
  • Find hosts automatically — mDNS discovery lists hosts on your LAN; saved hosts persist. First connect does a one-time SPAKE2 PIN pairing (or TOFU on trusted LANs), then reconnects on a pinned identity.
  • Per-host speed test to pick a bitrate, plus compositor and mode preferences in Settings.
  • Game library browser (experimental, off by default) — "Browse library…" on a saved host shows its games (Steam + custom) as a poster grid; click one to launch it in the session. Fetched from the host's management API over mTLS — paired devices are authorized by their certificate, no extra host setup.
  • Gamepad library launcher (--browse host) — a console-style, controller-driven library view of a paired host's games, rendered by the session binary's Skia console UI: A plays the focused title, B quits, L1/R1 jump. Built for the Steam Deck plugin's "Open library" launch; session end returns to the launcher. Arrow keys/Enter/Esc drive it too (no pad needed).

Get it

Most people should install a package rather than build from source:

Distro Install
Flatpak (any distro, Steam Deck) io.unom.Punktfunk — see packaging/flatpak
Ubuntu / Debian (apt) sudo apt install punktfunk-client (after adding the repo)
Fedora / Bazzite (rpm) rpm-ostree install punktfunk-client
Arch (PKGBUILD) see packaging/arch

Per-device install steps and pairing walkthrough: docs.punktfunk.unom.io/docs/install-client.

Build & run from source

Requires GTK ≥ 4.16, libadwaita ≥ 1.5, FFmpeg 7 or 8 (with VAAPI for hardware decode), PipeWire, and SDL3 (with hidapi) development packages.

# from the repo root
cargo run -p punktfunk-client-linux                 # launch the app
cargo run -p punktfunk-client-linux -- --connect HOST[:PORT]   # skip the host list and connect
cargo run -p punktfunk-client-linux -- --browse HOST           # the gamepad library launcher

The binary is named punktfunk-client — the relm4/libadwaita desktop shell (hosts, pairing/trust, settings, the desktop library page). Every stream and the console game library run in the sibling punktfunk-session Vulkan binary; the shell spawns it for connects, and --connect/--browse on the shell exec it directly (so the Decky wrapper keeps working unchanged). Headless flags stay in the shell: --pair <PIN> --connect host[:port] (pairing ceremony), --wake host[:port], and --library host[:mgmt_port] (print a host's game library).

Layout

src/
  main.rs · app.rs        entry point, relm4 AppModel (window, trust gate, session child
                          lifecycle, typed messages), primary menu, CSS
  cli.rs                  headless paths (--pair/--wake/--library), the --connect/--browse
                          exec handoff to punktfunk-session, screenshot scenes
  ui_hosts.rs             hosts page component (FactoryVecDeque cards, saved + discovered
                          grids, add-host dialog, banner)
  ui_library.rs           game-library poster grid (per-host, launches titles)
  ui_trust.rs             TOFU / PIN-pairing / request-access dialogs
  ui_settings.rs          resolution · refresh · decoder · bitrate · compositor · mic
  spawn.rs                the session-child plumbing (stdout contract → AppMsg)
tools/screenshots.sh      store screenshot capture (app self-capture; Xvfb fallback)

The UI-agnostic plumbing — session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads + keymap, trust store, mDNS discovery, library client, Wake-on-LAN — lives in crates/pf-client-core, shared with the Vulkan session binary.