enricobuehlerandClaude Opus 5
12abb47d26
WP1+WP2 of design/desktop-presentation-rebuild.md. The shared Linux/Windows session client presented arrival-paced with no pacing layer at all: two depth-2 newest-wins hops into a drain-to-newest and an immediate present. That IS the lowest-latency intent, but it was unnamed, unselectable, and had no alternative — and on a surface without MAILBOX (AMD's Windows driver offers none, and any compositor holding images does the same) the swapchain's own FIFO becomes a standing queue worth a measured 11-13 ms at 60 Hz. WP1 — the settings cluster, under the keys the Apple client already writes into the shared profile catalog (present_priority / smooth_buffer / vsync / allow_vrr): mismatched names would ride SettingsOverlay::extra, carried but never applied. PresentPriority::resolve mirrors the Android reference exactly (anything but an explicit "smooth" is latency; a buffer outside 1..=3 becomes 2), so a profile authored on any client means the same thing on all of them. Only the first two are consumed here; vsync/allow_vrr land in WP3. WP2 — the engine (present_pace.rs, pure state + arithmetic, 6 tests): - FrameStore: newest-wins slot, or the smoothing FIFO with preroll-to-capacity, drop-oldest overflow, and an underflow that re-arms the preroll (repeat by omission) — the Apple/Android semantics, with qDrop/qDry counters. - LatchClock: the panel grid learned from VK_KHR_present_wait glass stamps, min positive spacing capped by the mode refresh (measured, never queried — VRR and Android's per-uid refresh lie both punish trusting a reported rate). It now also publishes the host-facing LatchGrid, so the phase-lock report and the local scheduler cannot disagree about the grid. - PresentGate: one undisplayed present in flight on FIFO surfaces, with the 100 ms stale force-open. This is the standing-queue killer, and it is inert on MAILBOX/IMMEDIATE and without present timing — where behaviour stays byte-for-byte the shipped arrival pacing. Wiring: glass samples drain every pass (a 1 Hz batch would starve clock and gate) and the waiter pushes an SDL wake, so a gate reopen never waits out the event timeout; smoothness serves one frame per latch slot and tightens the loop's wait to that deadline; the adaptive slot margin starts at 0 and widens +500 us per missed window toward 2.5 ms (a fixed lead was measured to be pure display tax). PUNKTFUNK_PRESENTER=arrival disables the whole engine for field A/B without a rebuild. PyroWave collapses smoothness to latency for the stream: its plane-ring retirement accounting assumes the depth-2 newest-wins hand-off, and all-intra frames make buffering moot anyway. Gates (punktfunk-rust-ci, linux/amd64, sources touched first so a warm target cannot print a vacuous Finished): clippy -D warnings across pf-client-core, pf-presenter and punktfunk-client-session; 80 + 32 tests pass; rustfmt clean. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
punktfunk-session
The Vulkan session binary: one stream per invocation in an SDL3 window — no UI toolkit,
no widgets, terminal stats. The power-user / gamescope stream client, and the stage-2
presenter of the Linux client re-architecture (punktfunk-planning:
linux-client-rearchitecture.md).
This binary is deliberately dumb: a renderer the front-ends call INTO — the GTK shell
(punktfunk-client), the WinUI shell, and the punktfunk CLI all spawn it through the
same brain (pf_client_core::orchestrate), which resolves policy (profiles, settings,
wake) and hands the result down, normally as a --resolved-spec file. It reads the
shared stores only as the compat fallback for a bare hand-launched invocation.
punktfunk-session --connect host[:port] [--fp HEX] [--launch id] [--fullscreen] [--stats]
punktfunk-session --browse host[:port] [--mgmt PORT] [--fullscreen]
--browse opens the console game library (the Skia coverflow over the animated aurora)
instead of connecting: A launches the focused title as a stream in the same window,
session end returns to the library, B quits (Gaming Mode returns). Paired hosts only —
pairing is the desktop client / Decky plugin's job. PUNKTFUNK_FAKE_LIBRARY=<file.json>
feeds canned entries with no host (portrait paths starting with / load from disk).
Reads the same identity / known-hosts / settings stores as the desktop client
(punktfunk-client), so enrolling on either side makes the other work; this binary never
connects to a host it has no pinned fingerprint for (--fp HEX overrides the store).
Pairing is punktfunk pair <host> — the CLI, which ships alongside this binary in every
package and needs no window and no toolkit either. punktfunk-session --pair still works
for one release (someone's provisioning script calls it today) but prints a deprecation
notice: pairing is a trust ceremony and belongs to the brain, not a renderer.
Stdout is the machine interface: {"ready":true} after the first presented frame,
stats: … once per second while the overlay tier isn't Off (always the full detailed
text, whatever the OSD shows; --stats forces the overlay on), one
{"error"|"ended": …} JSON line on the way out. Logs go to stderr. Exit codes: 0
clean end, 2 connect failed, 3 trust rejected / pairing required, 4 presenter
init failed.
In-stream keys match the desktop client: click captures input (Ctrl+Alt+Shift+Q releases), Ctrl+Alt+Shift+D disconnects, F11 toggles fullscreen; the controller escape chord (L1+R1+Start+Select, hold to disconnect) works the same.
The default build carries the Skia console UI (ui feature): the stats OSD and capture
hint render in-window. Ctrl+Alt+Shift+S cycles the OSD tier live — Off → Compact (one
line: fps · latency · Mb/s) → Normal (mode + end-to-end percentiles) → Detailed (decoder
path + per-stage latency equation); any tier but Off also emits the stdout mirror.
--no-default-features is the ~5 MB power-user build — same streaming, stats on stdout
only, no Skia anywhere in the dependency tree.
Decode follows the Settings preference (auto: Vulkan Video → VAAPI → software on Linux,
Vulkan Video → D3D11VA → software on Windows): FFmpeg's Vulkan Video decoder runs on the
presenter's own device where the stack supports it (every vendor, zero copy); VAAPI
dmabufs import per-plane elsewhere (D3D11VA textures on Windows); software is the
universal fallback. 10-bit Main10 and HDR10 are advertised
(VIDEO_CAP_10BIT|HDR): P010 decodes through all three paths, and PQ streams present
on an HDR10/ST.2084 swapchain when the desktop offers one (KDE HDR, gamescope) or
tone-map in-shader to SDR when it doesn't (PUNKTFUNK_TONEMAP_PEAK tunes the rolloff,
default ≈1000 nits). The host still gates the upgrade behind its PUNKTFUNK_10BIT
policy.
Debug/bisect knobs: PUNKTFUNK_DECODER=vulkan|vaapi|d3d11va|software, PUNKTFUNK_PRESENT_MODE= mailbox|fifo|immediate|fifo_relaxed (default MAILBOX, FIFO where the surface offers no
MAILBOX — AMD on Windows), PUNKTFUNK_VK_DEVICE=<index> (multi-GPU), and
PUNKTFUNK_HW_FAULT=import (fault every VAAPI dmabuf import — proves the three-strike
demotion to software on healthy hardware).