drm: finish the logical-geometry comparison, and chain a re-raise

the pipewire-fallback guard now normalizes BOTH sides to logical before
comparing. last round fixed only the single-display case, which left
the same defect on the shape that actually has it: on a multi-monitor
scaled host the advertised geometry carries the PHYSICAL drm mode plus
the compositor scale, while the portal rect is already logical, so a
scaled output disagreed with itself (2880x1800 against 1440x900) and a
per-connector stream that really was that display was rejected,
leaving it advertised offline instead of degrading. the size check
itself stays: on a multi-monitor host it is what tells one connector
apart from the whole-desktop rect. the failure message reports the
logical numbers, the ones actually compared.

also chains the libdrmtap read failure with `from err` so the original
OSError survives (ruff B904).
This commit is contained in:
Mariano Abad
2026-07-30 14:50:21 -03:00
parent f524d41279
commit 0035c89763
2 changed files with 27 additions and 15 deletions

View File

@@ -488,7 +488,7 @@ def _assert_so_has_egl(so_path):
with open(so_path, 'rb') as f:
blob = f.read()
except OSError as err:
raise Exception(f'cannot read the built libdrmtap at {so_path}: {err}')
raise Exception(f'cannot read the built libdrmtap at {so_path}: {err}') from err
missing = [m for m in (b'libEGL.so.1', b'eglCreateImageKHR') if m not in blob]
if missing:
raise Exception(

View File

@@ -457,25 +457,37 @@ pub(super) fn get_capturer_for_display(
None => (None, false),
};
if let Some(advertised) = advertised {
// The advertised DRM geometry is PHYSICAL while the PipeWire rect is the
// compositor's LOGICAL size (try_fix_logical_size), so on a scaled output the
// two sizes legitimately disagree (2880x1800 vs 1440x900) even when the stream
// IS this display. On a single-display host the whole-desktop stream is this
// display by construction, so only the position has to agree there; comparing
// the physical size too rejected the one valid fallback and restart-looped the
// display instead of degrading. On a multi-monitor host the size check stays:
// it is what tells one connector apart from the full-desktop rect.
// Compare LOGICAL against LOGICAL. The advertised DRM geometry carries the
// PHYSICAL mode plus the compositor scale (augment_with_wayland_geometry sets
// x/y/scale and deliberately leaves width/height physical), while the PipeWire
// rect is already logical (try_fix_logical_size). Comparing the two raw made a
// scaled output disagree with itself -- 2880x1800 against 1440x900 -- and the
// guard then rejected a portal stream that really was this display, leaving it
// advertised offline instead of degrading to PipeWire.
//
// The size check itself stays, because on a multi-monitor host it is what
// tells a single connector apart from the whole-desktop rect the portal
// usually exposes. On a single-display host that rect IS this display by
// construction, so only the position has to agree.
let scale = if advertised.scale > 0.0 {
advertised.scale
} else {
1.0
};
let logical_w = (advertised.width as f64 / scale).round() as usize;
let logical_h = (advertised.height as f64 / scale).round() as usize;
let consistent = advertised.x == rect.0 .0
&& advertised.y == rect.0 .1
&& (single_display
|| (advertised.width as usize == rect.1
&& advertised.height as usize == rect.2));
&& (single_display || (logical_w == rect.1 && logical_h == rect.2));
if !consistent {
// Report the LOGICAL numbers, the ones actually compared, so the message
// does not look like a mismatch of quantities that were never expected to
// match on a scaled output.
bail!(
"drm display {} demoted with no geometry-consistent PipeWire stream (advertised {}x{}+{}+{} vs stream {}x{}+{}+{}); advertised offline",
"drm display {} demoted with no geometry-consistent PipeWire stream (advertised {}x{} logical +{}+{} vs stream {}x{}+{}+{}); advertised offline",
display_idx,
advertised.width,
advertised.height,
logical_w,
logical_h,
advertised.x,
advertised.y,
rect.1,