enricobuehler
370b0ab494
Closes M2. The 2026-08-05 ladder decision: WP-D shut with bit-exact
parity vs libavcodec (250/250 AUs on RADV, AMD-proprietary and NVIDIA)
and a 92-minute clean soak, and the program's goal is dropping FFmpeg
from the client — so on H.264 sessions where caps pass, auto now tries
pf-vkdecode FIRST, exactly where the ladder would reach FFmpeg-Vulkan.
No bake period.
native_vulkan_gate widens from by-name-only to the auto family
(auto/""/hardware); the vendor-first rungs are untouched (Linux
Intel/unknown still VAAPI-first, Windows Intel/unknown still
D3D11VA-first — NVIDIA and ALL AMD go native first). A native INIT
failure or caps refusal logs and falls through to FFmpeg-Vulkan, so
admission can't cost a session its decoder at start; runtime error
streaks ride the existing demotion machinery unchanged (past
FFmpeg-Vulkan to VAAPI/D3D11VA/software — a native→FFmpeg-Vulkan
runtime rung is deliberately absent, FFmpeg is on its way out).
PUNKTFUNK_DECODER=native-vulkan stays as the explicit pin; vulkan
keeps naming the FFmpeg backend specifically. A native_tried guard
keeps a failed pin init from re-attempting construction in auto.
Review round 8 (adversarial): no blocking code defect — no demote
bounce-back (Decoder::new is session-start-only; demotion mutates in
place), no double attempt, no cfg imbalance. 5 findings fixed: two doc
overclaims ("nothing regresses" now scoped to init; the ladder
enumerations no longer claim desktop-AMD Linux is VAAPI-first —
prefer_vulkan_first is vendor-wide), stale opt-in claims in Cargo.toml,
stale user-facing ladder text (console-ui row, trust.rs decoder field,
session README incl. the env-knob list), and the gate test now pins the
H264 codec-op bit to the literal 0x1 so a typo'd constant can't make
native silently never engage.
Gates: fmt clean; container clippy -D warnings zero for pf-client-core +
pf-presenter + pf-vkdecode; container tests green (pf-client-core lib +
pf-vkdecode + pf-bitstream); pf-console-ui check clean; mac
pf-vkdecode/pf-bitstream/cros-codecs 167 tests green.
On-glass sanity CLOSED 2026-08-05 ~22:10 UTC on .173 (4090, coincide
mode), decoder=auto and NO env var: the ladder picked native on its
own ("pf-vkdecode auto rung" log line), 525/526 stats windows on
native-vulkan over ~8m46s / 31550 frames, fps 0/59.4/61 with 6
windows <55 incl. startup zeros, bad-signature grep over the whole
log EMPTY, zero TDR events, host service Running after teardown.
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 is vendor-ordered: hardware Vulkan Video →
VAAPI → software on Linux, hardware Vulkan Video → D3D11VA → software on Windows, with
VAAPI/D3D11VA first on Intel; on H.264 the native pf-vkdecode Vulkan decoder is tried
immediately before FFmpeg-Vulkan): the Vulkan decoders run 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=native-vulkan|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).