enricobuehlerandClaude Fable 5
4a01bc4463
The host cursor stops riding the video and becomes a real OS cursor on the client (the Parsec/RDP model): pointer feel no longer pays the capture→encode→network→decode→present round trip. Wire (M2a): - Hello grows a client_caps trailing byte (CLIENT_CAP_CURSOR) after the fixed display_hdr block — presence disambiguated by remaining length, which caps the post-HDR tail at 27 bytes (documented); Welcome answers HOST_CAP_CURSOR (capable-and-asked, the 444/clipboard precedent). - CursorShape (0x50, control stream): serial + dims + hotspot + straight RGBA, ≤120px/side so the u16 frame always fits (128² would overshoot); client caches by serial — re-showing a known shape costs 14 bytes, not a bitmap (RDP pointer-cache for free). - CursorState (0xD0 datagram): serial + visible/relative_hint flags + position, sent once per encode-loop tick — latest-wins, self-healing under loss, no refresh timer. relative_hint is reserved for M3. - Client core: two new planes (control-task + datagram-task arms) → next_cursor_shape/next_cursor_state; connect() grows client_caps (C ABI passes 0 until the v11 cursor poll fns exist). Host (M2b, Linux portal only): - handshake::cursor_forward is THE predicate (client asked ∧ Linux ∧ compositor ≠ gamescope) — Welcome bit and session wiring both read it. - SessionPlan.cursor_blend goes false for a forwarding session; the encode loop ticks a CursorForwarder every iteration: shape-serial diff → control-task bridge (mirrors probe_result), state datagram → conn. - CursorOverlay/capture CursorState carry the hotspot through (nearest-neighbor downscale backstop for XL cursors, unit-tested). Presenter: - CursorChannel drains both planes per loop iteration; shapes become SDL color cursors (from_surface + hotspot), applied while the desktop mouse model is engaged; visibility follows the host; capture/released hands back the system cursor. Sessions advertise the cap when they START in desktop mode. Verified on .21: fmt + clippy -D warnings (7 crates) + tests green (core 218 incl. new wire roundtrips, host 245 incl. e2e + forwarder downscale tests). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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.
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