Accumulated qt-frontend work from the 2026-08-11/12 sessions (cc),
uncommitted until now: the app-wide dynamic background in both modes
(AmbientField with GPU/Canvas arms, AppShell layering, ambient palette
pipeline), the wave-1 clip/batch sweep across the tree (alpha batches
449 -> 327, reproducible), the rounded-cover and icon-tint arms, and
scripts/qt-batches.sh (batches + presents/s sampler).
The GPU behaviour of these pieces was finalized in the follow-up pulse
commits; see qbz-nix-docs/qt-frontend/2026-08-11-scenegraph-batches/
GPU-COST-INVESTIGATION.md for the full campaign.
km
Two defects with one cause: a tint name that means a frozen hex.
"primary" is the legacy alias of literal #ffffff, not Theme.text-primary,
so every control passing it drew a white glyph. On the eleven light
themes that is white-on-light -- the header back/forward chevrons, the
sidebar toggle and the carousel arrows the owner marked. They now pass
the theme-following names, which icon_tint_qt bakes at runtime.
The stale `hslLightness > 0.5 ? "primary" : "black"` workarounds that
predate the runtime tinter collapse into those names, and the qrc floor
underneath them becomes polarity-aware: dir_for() returns "" whenever
the cache dir is unavailable, a bake fails or the theme document has not
been published, and that path used to resolve textPrimary straight back
to the white bake -- reproducing the bug it was fixing, app-wide, in the
degraded state.
On accent fills the fix is a deviation from Slint, approved by the owner
after measurement. A fixed white glyph on Theme.accent falls under 2.6:1
on 16 of the 35 shipped palettes, including high-contrast at 1.70:1 and
wcag-dark at 1.82:1 -- the two themes whose reason to exist is contrast.
Slint hardcodes #ffffff there (CircleAction.slint:72 and three others),
so the bug is upstream. accentText alone is not the answer either: it is
picked for the theme's text ramp and gives 2.56:1 on Rose Pine Dawn,
worse than the black it replaces. So QbzTheme picks the best-contrast
tint by real sRGB luminance against the live accent, and the labels
beside those glyphs use its colour twin -- BrowseGenreButton and
LibraryView were drawing a white glyph next to an accentText label
inside the same pill.
Rounds out the two parity items the same files owe: QbzNavButton gains
the ambient arm from Carousel.slint (wired at the six carousel sites,
not left dead), and QbzCircleAction rounds its glyph to whole pixels the
way CircleAction.slint does.
cc
**Deferred external rows.** The album page awaited the Last.fm row before
publishing anything, so the tracklist waited on an external service plus
MusicBrainz. It publishes in stages now — header and tracks first, then each
Qobuz rail as it lands, then Last.fm — with every patch merged under a
generation counter so a late reply for album A cannot paint onto album B. The
artist page was already staged this way; its views were the part still showing
bare "Loading…" text.
**Skeletons as the standard.** One control, new variants rather than new
components, mounted across the views. Its second job is the one the owner
named: cleanup. A cover that never resolves settles the placeholder once and
reveals the card's own empty state instead of shimmering forever — local albums
with no embedded art produce no artwork entry at all, so a placeholder gated
only on "not arrived yet" would never stop.
**Local artwork streams.** Fifteen seconds to first cover on a 1274-album grid
was one batch emitted after the whole window resolved. Each cover emits as it
resolves now, visible band before prefetch margin.
**Lyrics migrated.** Smooth sync instead of a 1 Hz tick, word-level karaoke
where the document carries it, the surrounding-line dimming, the controls
flyout and the translation layer the v10 backend already supported. Exactly one
row subscribes to the 30 Hz output; the timer drops to 250ms when paused or
hidden.
**Navigation by mouse and touchpad.** Side buttons and a two-finger horizontal
swipe, matching #653 — including the part that matters, which is that a swipe
over a carousel scrolls the carousel. The layer is declared first in the shell
so everything else gets first refusal.
**Context menus.** Brought to the Slint inventory, Play later included, with
right-click opening the same menu as the button everywhere. Entries whose seam
does not exist are hidden rather than shipped inert.
Two controls that rendered and no-opped are now honestly disabled: the My QBZ
nav row, which routes to a view the shell has no case for, and three sidebar
menu entries with no backing call.
The sidebar caret was never a condition bug. The row is a positioner and the
name cell's width ignored the count label, so a folder WITH content pushed the
chevron past the clip — which is why it vanished exactly when it mattered.
cc
Two fronts of the modularization, both gated green before this commit.
QML leaves the flat qml/ directory for seven modules: cards, controls,
rows, settings, shell, theme, views. Only Main.qml and LoginScreen.qml
stay at the root. build.rs matches the tree exactly (55 files), relative
imports and asset paths were re-anchored for the new depth.
The QbzBridge God-object starts breaking up: QbzSession, QbzShell,
QbzPlayer, QbzQueue and QbzHome are now their own #[cxx_qt::bridge]
singletons, each with its own OnceLock<CxxQtThread> and ui() hop, booted
in order from Main.qml. Bridge files stay directly under src/ because
cxx-qt-build only accepts rust_files from one directory (QTBUG-93443).
bridge.rs keeps 5.5 domains (library, album/artist, settings,
integrations, search, playlist) and dies once they are split out.
cc
vicrodh