enricobuehler
73c911cae4
Rumble was level-triggered, unbounded state on a lossy channel: a non-zero level meant "buzz until further notice", healed only by the host re-sending state every 500 ms, and every client guessed when the host had died with its own magic timeout (SDL 1.5 s, Apple 1.6 s, Android up to 60 s). A lost stop, a reordered start, or a dead host could drone the motor for seconds. Make "stuck rumble" inexpressible on the wire. The 0xCA datagram grows a length-tolerant tail — [u8 seq][u16 ttl_ms] — so it self-terminates: the host authorizes a level for at most ttl_ms and renews it (~120 ms) while it holds, letting an abandoned one lapse client-side. seq is a per-pad wrapping reorder gate (reusing GamepadSnapshot::seq_newer) so a reordered stale start can't re-light a stopped motor. Decoders read the first 7 bytes as a plain level and ignore the tail, so no wire-version bump: an old client renders a new host's levels, and a new client falls back to its prior staleness heuristic against an old host (ttl = None). All four generation pairings render correctly. - core: encode_rumble_datagram_v2 / decode_rumble_envelope (datagram.rs); the client demux applies the seq gate then forwards (pad, low, high, Option<ttl>); next_rumble is unchanged (drops ttl), next_rumble_ttl keeps it; ABI adds punktfunk_connection_next_rumble2 + PUNKTFUNK_RUMBLE_NO_TTL, ABI_VERSION 4->5 (WIRE_VERSION unchanged — the tail is backward-compatible). - host (punktfunk1.rs): the flat 500 ms refresh becomes a renewal loop that bumps seq + stamps a fresh TTL on active pads and drains a short post-stop zero burst, then goes quiet. Hatches: PUNKTFUNK_RUMBLE_ENVELOPE=0 (legacy v1 + flat refresh, a bisect switch), PUNKTFUNK_RUMBLE_TTL_MS (clamped [150, 5000]). - renderers honor the TTL as their playback duration/deadline and keep their old heuristic only for a legacy (ttl=None) update: pf-client-core (the Deck haptic keep-alive is now deadline-bounded so it can't sustain a host-stopped rumble), clients/windows (SDL duration), android (JNI packs the lease out-of-band in bit 48 so any u16 ttl is unambiguous; Kotlin createOneShot(ttl)), apple (RumbleRenderer.envelopeDeadline + nextRumble2; sessionStaleSeconds demoted to the legacy fallback). - tests: codec round-trip + tail tolerance + seq-gate reorder (Rust); the probe asserts the v2 tail arrived under PUNKTFUNK_TEST_FEEDBACK; the Apple loopback asserts ttlMs round-trips end to end; RumbleTuning lease-decision cases. The host-side idle-timeout from the previous commit is defense in depth on the game side; this is the guarantee on the client side. Design: punktfunk-planning/design/rumble-envelope-plan.md. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
punktfunk-host
The streaming host — the program you run on the machine whose desktop or games you want to stream. For each client that connects, it spins up a virtual display sized to that device, captures it on the GPU, encodes with hardware NVENC/VAAPI/AMF/QSV, and sends it out over a low-latency transport — no physical monitor, no letterboxing, no rearranging your real screens.
It speaks two protocols from one process:
- GameStream — so any Moonlight / Artemis client works day one.
punktfunk/1— punktfunk's own faster protocol (QUIC control plane, GF(2¹⁶) FEC + AES-GCM data plane) that the native clients use.
Runs on Linux (the primary, most battle-tested path) and Windows (x64). The shared protocol,
FEC, and crypto live in punktfunk-core; this crate is everything
platform-facing around it.
What it does
- Per-client virtual displays at the exact WxH@Hz. Linux uses per-compositor backends — KWin, gamescope, Mutter, and Sway/wlroots; Windows uses its own all-Rust IddCx virtual display, even on the secure desktop (UAC / lock screen).
- GPU zero-copy capture → encode. dmabuf → CUDA/Vulkan → NVENC on Linux; on Windows the host pushes frames straight into its own IDD (sealed IDD-push, no screen-scraping) → GPU encode. Encoders auto-select by GPU vendor: NVENC (NVIDIA), VAAPI (Linux AMD/Intel), AMF/QSV (Windows AMD/Intel), or software H.264 as a floor. HDR/10-bit and HEVC 4:4:4 supported.
- Input injection. Mouse/keyboard (libei / gamescope EIS / wlr / Windows SendInput) and virtual gamepads — Xbox 360/One, DualSense, DualShock 4 — with rumble and HID feedback back-channels.
- Audio both ways. Opus audio host→client, plus a virtual microphone the client can talk into.
- Trust & discovery. A persistent host identity, SPAKE2 PIN pairing (default) or TOFU, and mDNS auto-advertisement so clients find the host without typing an IP.
- Management API + web console. A REST API (
mgmt.rs, OpenAPI atapi/openapi.json) drives status, paired devices, and on-demand pairing; the browser UI is inweb/.
Run it
punktfunk-host serve runs inside your desktop session. Bare serve is the secure native-only
default (punktfunk/1 + the management API); add --gamestream on a trusted LAN to also accept
stock Moonlight clients.
# Linux, from the repo root (see the repo README "Running on this box" for the headless recipe):
cargo run -rp punktfunk-host -- serve # native-only (secure default)
cargo run -rp punktfunk-host -- serve --gamestream # + Moonlight compatibility
Then pair from the web console (https://<host-ip>:47992) or the client app.
Most people should install a package rather than run from source — see
packaging/ (apt · rpm/COPR/bootc · Arch/sysext · Windows installer) and
the per-platform guides at docs.punktfunk.unom.io/docs/install.
Subcommands
| Command | Purpose |
|---|---|
serve |
The host (native punktfunk/1 + mgmt API; --gamestream adds Moonlight). |
punktfunk1-host |
Standalone native-protocol listener for testing/measurement (--source virtual, --max-sessions). |
openapi |
Print the management-API OpenAPI spec (regenerates api/openapi.json). |
library |
Inspect the multi-store game library. |
service · driver · web |
Windows: SCM service, driver install, bundled web console. |
*-test / *-selftest / *-probe |
Diagnostics (input, zero-copy, HDR, compositor, gamepads). |
--help lists them all.
Layout
src/
main.rs CLI + subcommand dispatch
config.rs · session_plan.rs · session_tuning.rs · pipeline.rs session setup + the frame pipeline
vdisplay/ per-compositor virtual outputs (kwin · gamescope · mutter · wlroots)
capture/ · capture.rs screen/dmabuf capture (+ Windows IDD-push)
encode/ · encode.rs per-GPU encoders (nvenc · vaapi · ffmpeg_win (AMF/QSV) · sw)
linux/zerocopy/ dmabuf → CUDA → NVENC bridges (EGL/GL tiled, Vulkan LINEAR)
inject/ · inject.rs input backends (libei · wlr · uinput gamepads · UHID DualSense/DS4)
audio/ · audio.rs Opus out + virtual mic (PipeWire / WASAPI)
gamestream/ Moonlight compat: nvhttp · pairing · rtsp · control · stream · gamepad · apps
punktfunk1.rs the native punktfunk/1 host (QUIC control + native-thread UDP data plane)
mgmt.rs · native_pairing.rs · stats_recorder.rs management API, pairing, perf capture
hdr.rs · library.rs HDR metadata; multi-store game library
linux/ · windows/ platform-confined backends
Related
punktfunk-core— the shared protocol · FEC · crypto core- Clients — the apps that connect (Apple · Linux · Windows · Android · probe)
- Packaging & docs — install & operate
- punktfunk-planning (internal planning repo) — architecture rationale and deep-dive plans