G17's motion half. The docs described what the CLIENT sends and stopped there, which
made a promise the host does not always keep.
The support matrix said a desktop client forwards motion from any pad SDL exposes a gyro
on "and the host injects it into the matching virtual pad". The first clause is true; the
second is only true when the virtual pad has a motion plane. The X-Box 360 and One
backends do not — no gyro in their HID contract — so the host parses every sample and
discards it. That is where *Automatic* lands anything it does not recognise as Sony or
Valve, an 8BitDo with a perfectly good gyro included, and where a Switch Pro lands on a
Windows host with no `hid-nintendo` backend to fold it into.
A reader following the old text would conclude their gyro was broken. The failure has no
other symptom: motion just does nothing.
So both pages now say what to do about it — pick a DualSense-class type — and the
client-settings page says it where the choice is actually made, next to the degrade
paragraph that explains why a session ends up on an X-Box pad in the first place.
The Deck's Steam-Input requirement moves out of Decky's settings blurb, which is the one
place a Deck user streaming FROM the Deck would never look. With Steam Input on, Steam
hands the app its own virtual X-Box pad, so no controller-type choice can help: there is
no gyro on the pad the client can see.
The picker help text now mentions motion on GTK and Android, which is where it was
missing — Windows already said it and Apple says it in its own words. One sentence, the
same sentence, so the four clients answer the question the same way.
This is the doc side of the on-screen notice that shipped earlier in this branch. The two
exist for the same reason and now agree: the client says it when it detects the case, the
docs say it when someone goes looking.
Not covered: the preset COUNTS in note 1 ("Android and the console home offer six …
Windows and Apple offer five") are still unverified against the four pickers, and the
Apple picker's missing Steam Deck entry is a code gap rather than a doc one. Both are
noted in the plan and left for their own change rather than guessed at here.
Gate: Linux CI image fmt + `clippy --locked --all-targets -D warnings` on
punktfunk-client-linux (the GTK string is compiled) plus the core crates and their tests;
Android `:app:compileDebugKotlin` + `:app:testDebugUnitTest`. Green.
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, and it's ours — the session presenter decodes with Punktfunk's own
decoders; no FFmpeg is linked or bundled. Vulkan Video (
pf-vkdecode, decoding onto the presenter's own device) leads on NVIDIA and AMD, VAAPI (pf-vaadecdriving a dlopen'd libva, exporting DRM-PRIME dmabufs) leads on Intel, whichever isn't first is the fallback, and an OpenH264/rav1d CPU rung is last. - 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, PipeWire, and SDL3 (with hidapi) development packages, plus a C compiler (the CPU rung builds OpenH264 from source). No decoder development package is needed: libva and the Vulkan loader are both opened at runtime rather than linked, so hardware decode is a fact about the box you run on — a Vulkan loader and your GPU's driver, and libva for the VAAPI rung — not about the one you build on.
# 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, the native decode ladder (Vulkan Video · VAAPI ·
OpenH264/rav1d), 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.
Related
- Documentation — quick start, pairing, troubleshooting
- Steam Deck plugin — launches this client fullscreen in Gaming Mode
- Project README — the host, the other clients, and how it all fits together