Vendor i-slint-core 1.16.1 with a one-rule patch in sharedparley's
line culling: with overflow: elide, every line whose bottom edge
exceeded max_height was dropped — INCLUDING the first one, eliding the
text to literally nothing. CJK fallback fonts report line metrics
taller than snug fixed-height boxes (Hiragino at 14px measures ~21px
inside TrackRow's 20px title line), so on macOS every CJK track title
rendered blank while Latin titles fit; Linux survived because Noto's
metrics fit the box. Root-caused with a headless render matrix on the
Mac Mini: the verbatim TrackRow structure reproduced the blank title,
removing elide rendered it, and the patched core renders all variants.
The first line still receives the ellipsis treatment as the last
visible line.
This is the real #543 mechanism. The earlier femtovg render_glyph
retry (3a1c367d) addressed a different, hypothesized layer and stays
as harmless defense in depth.
Fixes#543
cc
Vendor femtovg 0.23.2 with a targeted patch: the swash raster path can
fail to scale some variable fonts at a non-default variation instance
(the CFF2-based CJK system fonts on modern macOS), and femtovg cached
those glyphs as permanently missing — so track titles and any other
text at medium/semibold/bold weight rendered blank for CJK while
regular weight (empty coords) worked. render_glyph now retries the
glyph at the font's default instance before giving up: worst case the
glyph draws at regular weight instead of not at all. Fonts and
instances that already render are untouched.
Fixes#543
cc
fontique's CoreText-based Han-script fallback fails to resolve a family on
modern macOS (the suggested PingFang is not always in the scanned family
map), so Japanese kanji rendered blank while kana worked. Vendor
i-slint-common 1.16.1 and pre-register Hiragino / PingFang / Apple SD
Gothic Neo / Arial Unicode MS in the fallback map at collection creation
(Japanese-biased default; the map takes priority over the CoreText query).
macOS-only cfg; Linux keeps its working fontconfig fallback. Type-checked
against aarch64-apple-darwin.
cc
Weak-GPU hardware (Raspberry Pi 4 / v3dv, Haswell / hasvk) exposes a
real Vulkan adapter, so the old binary wgpu-or-software detection handed
it the slowest possible path: femtovg-wgpu over an immature Vulkan
driver. Mesa's GL path is the fast one on that class of hardware.
- Three-tier chain: wgpu -> femtovg GL -> software. Auto-detect
classifies adapters (weak-driver markers incl. hasvk, integrated-on-arm,
tiny texture limits); adapters only reachable through wgpu's GL backend
never select the wgpu tier (the renderer masks Backends::GL out, so
detection must too). renderer-femtovg (GL) feature now compiled on
Linux.
- wgpu tier requests PowerPreference::LowPower (WGPU_POWER_PREF still
wins).
- Per-window swapchain alpha in the vendored femtovg renderer: only the
miniplayer gets a transparent (blended) swapchain; the main window
keeps an Opaque one, sparing a full-window compositor blend per frame.
- Settings > Appearance gains a Renderer row (Linux only): Auto
(default) / GPU / GPU compatibility / Software, persisted in
ui_prefs.json, applied on restart. QBZ_RENDERER env still overrides
(now also accepts gl|gles|femtovg).
- Auto-revert sentinel: a non-auto choice is armed before backend init
and disarmed after the window survives 5s; if the previous start died
before that, the setting reverts to Auto with an explanatory toast, so
a bad renderer pick can never lock the user out of Settings.
- Developer tools > Diagnostics now reports the active renderer, why it
was chosen, and the enumerated GPU adapters (panel + markdown report).
cc
Slint 1.16's femtovg-wgpu renderer configures the wgpu surface via
get_default_config() and leaves the composite alpha mode at Auto, which
resolves to an opaque surface on KWin/Wayland — a borderless transparent
window then shows a black rectangular backing behind the rounded card.
WGPUConfiguration exposes no surface/alpha hook, so the only fix is a
renderer patch.
Vendor i-slint-renderer-femtovg-1.16.1 with a preferred_alpha_mode() that
picks a supported non-opaque mode (PreMultiplied / PostMultiplied /
Inherit, guarded by the surface's advertised alpha_modes, else Auto) and
wire it into set_surface(). Pulled in via [patch.crates-io]; Slint stays
pinned =1.16.1. The main window is unaffected (it paints opaque).
cx
vicrodh