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 — Windows client
The native Windows app for streaming a punktfunk host to your PC. A modern WinUI 3 app that discovers hosts on your network, pairs with a PIN, and streams at your display's own resolution and refresh rate — with a hardware-accelerated D3D11 video path and HDR.
It's pure Rust: the UI is WinUI 3 driven through windows-reactor
(a declarative, React-like framework), and it links the shared punktfunk-core directly to speak
the fast punktfunk/1 protocol.
Features
- Hardware decode, GPU present — FFmpeg HEVC with a D3D11VA zero-copy path (decoder and
presenter share one D3D11 device; NV12/P010 textures sampled straight into a
SwapChainPanelcomposition swapchain), with a robust software-decode fallback. - HDR10 — advertise 10-bit/HDR, detect PQ in-band, and flip the swapchain to
R10G10B10A2+ ST.2084 with HDR10 metadata. - Your display's native mode — the host builds a virtual display at exactly your WxH@Hz.
- Audio both ways — WASAPI render + mic capture.
- Full controller support — SDL3 gamepads with rumble, lightbar, and DualSense feedback.
- Your display's native mode, really — "Native display" resolves the actual size + refresh of the monitor the window is on at connect time.
- Find hosts automatically — mDNS discovery lists hosts on your LAN, alongside saved and manual entries. First connect does a one-time SPAKE2 PIN pairing (or TOFU on trusted LANs), then reconnects on a pinned identity. Saved hosts carry per-host actions: a network speed test (probe burst over the real data plane → recommended bitrate, applied in one tap) and forget.
- Polished shell — host cards, settings (resolution / refresh / host compositor / decoder / codec / bitrate / HDR / forwarded controller / gamepad type / system shortcuts / audio channels / mic / stats-overlay level), the tiered stats overlay (Off / Compact / Normal / Detailed — Ctrl+Alt+Shift+S cycles it live in the session window), and the full trust surface. Stream input uses Win32 low-level hooks with Moonlight-style capture: Ctrl+Alt+Shift+Q releases the pointer, a click on the stream re-captures it, and system shortcuts (Alt+Tab, Win, …) can act locally or forward to the host.
Builds and ships for both x64 and ARM64 as a signed MSIX.
Get it
Install the signed MSIX from the package registry — see docs.punktfunk.unom.io/docs/install-client. A stock Moonlight client also works over GameStream if you prefer.
Build from source
Windows-only (the crate builds as a stub on other platforms so the workspace stays green). You need
the MSVC toolchain, an FFMPEG_DIR FFmpeg tree, and CMake (SDL3 builds from source). windows-reactor's
build.rs downloads the Windows App SDK NuGets and needs CARGO_WORKSPACE_DIR set.
cargo build -p punktfunk-client-windows --target x86_64-pc-windows-msvc
# CLI paths for testing (no window):
punktfunk-client --discover # list hosts on the LAN
punktfunk-client --headless --connect host[:port] [--pin HEX] # connect, count frames, print stats
punktfunk-client --headless --speed-test --connect host[:port] # probe burst → recommended bitrate
CARGO_HOMEmust be an ASCII path — non-ASCII characters break SDL3's MSVC precompiled-header build. Packaging (MSIX manifest, signing) lives inpackaging/.
Layout
src/
main.rs entry point + CLI paths (--discover · --headless · --speed-test)
app/ WinUI 3 shell (windows-reactor), one module per screen:
mod (root/router) · hosts · connect · pair · speed · settings ·
licenses · stream · style (shared cards/pills/monograms)
present.rs · gpu.rs SwapChainPanel D3D11 composition swapchain; shared D3D11 device
video.rs FFmpeg HEVC decode (D3D11VA zero-copy + software fallback)
audio.rs WASAPI render + mic capture
gamepad.rs SDL3 controllers + rumble/lightbar/DualSense feedback
input.rs Win32 low-level hooks → host input (pointer lock · click-to-capture)
session.rs session lifecycle over the NativeClient connector (+ speed probe)
trust.rs · discovery.rs persistent identity, TOFU/PIN pairing, mDNS browse
packaging/ MSIX manifest, signing, pack script
Related
- Documentation — quick start, pairing, troubleshooting
- Project README — the host, the other clients, and how it all fits together