enricobuehler
27a5d8daac
vdisplay.rs + vdisplay/* (the per-compositor Linux backends — KWin zkde-screencast,
wlroots swaymsg, Mutter RemoteDesktop, Hyprland — and the Windows IddCx/pf-vdisplay
driver backend, behind one VirtualDisplay trait; the mode-conflict admission
registry, the display policy/identity/custom-preset state, and the session-env /
gamescope routing) move into crates/pf-vdisplay (plan §W6). The DDC/CI panel-power
control (used only here) and the KWin zkde protocol XML move with it. This
completes the host-crate decomposition: capture, encode, inject, and vdisplay are
now four subsystem crates over the shared leaves, and punktfunk-host is the
orchestrator (serve/supervisor + native + gamestream + mgmt).
Coupling breaks (all down-only, cargo-tree acyclic):
- capture::dxgi identity -> pf_frame::dxgi; win_display/monitor_devnode/
console_session_mismatch -> pf-win-display leaf; can_open_another_session ->
pf-encode (the NVENC session-budget admission gate — acyclic peer edge).
- The registry's DisplayCreated/DisplayReleased emits into the host SSE event bus
invert to a leaf hook: pf-vdisplay emits a neutral DisplayEvent to a
host-registered DISPLAY_EVENT_SINK, so it never reaches the orchestrator's
events module.
- The IddCx driver module is renamed pf_vdisplay -> driver (its old name collided
with the crate name through the host's `mod vdisplay` shim glob).
The host keeps `mod vdisplay { pub use pf_vdisplay::* }` so every crate::vdisplay::*
path (serve/mgmt/native/the capture FrameChannelSender seam) is unchanged; the
heavy deps (wayland/ashpd/tokio + the zkde protocol) moved with the crate.
Co-authored: a fail-closed IOCTL-reply-length security fix (reject short/zeroed
pf-vdisplay driver replies before trusting protocol_version/target_id/wudf_pid/luid,
security-review 2026-07-17) rides this commit in the moved driver module.
Verified: Linux clippy -D warnings (pf-vdisplay + host nvenc,vulkan-encode,pyrowave
--all-targets) + pf-vdisplay 63/63 + host 167/167 tests; Windows clippy -D warnings
(pf-vdisplay --all-targets + host nvenc,amf-qsv --all-targets) Finished exit 0.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
979 lines
42 KiB
Rust
979 lines
42 KiB
Rust
//! GNOME/Mutter virtual-display backend via Mutter's *direct* D-Bus APIs (the same path
|
||
//! gnome-remote-desktop uses for headless sessions — not the xdg portal, which needs an
|
||
//! interactive grant):
|
||
//!
|
||
//! 1. `org.gnome.Mutter.RemoteDesktop.CreateSession()` → a remote-desktop session (read its
|
||
//! `SessionId`). The cast is anchored to it, and it's also the future input path.
|
||
//! 2. `org.gnome.Mutter.ScreenCast.CreateSession({"remote-desktop-session-id": id})`.
|
||
//! 3. `ScreenCast.Session.RecordVirtual({"cursor-mode": embedded})` → Mutter creates a **virtual
|
||
//! monitor** and returns a Stream object.
|
||
//! 4. `RemoteDesktop.Session.Start()` → the Stream signals `PipeWireStreamAdded(node_id)`.
|
||
//!
|
||
//! The virtual monitor's *size* follows the PipeWire format negotiation — Mutter adapts it to
|
||
//! what the consumer asks for — so the client's exact WxH is plumbed into our consumer's format
|
||
//! pod as the preferred size ([`VirtualOutput::preferred_mode`]) rather than passed here.
|
||
//! Sessions die with the D-Bus connection, so a keepalive thread owns it (RAII teardown).
|
||
//!
|
||
//! Requires a running Mutter (`gnome-shell` session, or `gnome-shell --headless` for the
|
||
//! headless host) on the session bus. GNOME is detected via `XDG_CURRENT_DESKTOP=GNOME` or
|
||
//! forced with `PUNKTFUNK_COMPOSITOR=mutter`.
|
||
//!
|
||
//! **Per-client scaling** (`identity` policy §5.4): GNOME persists per-monitor scale to
|
||
//! `monitors.xml` keyed by connector+vendor+product+**serial**, but Mutter mints a fresh serial
|
||
//! (`0x%.6x`, a per-shell counter) for every `RecordVirtual` monitor and the API offers no way to
|
||
//! pass a stable identity — so GNOME's own persistence can never rematch our virtual output. The
|
||
//! host persists the scale instead ([`identity::ScaleMap`](crate::identity), keyed per
|
||
//! client / per the policy): reapplied at connect via the mode's `preferred-scale` plus the
|
||
//! topology `ApplyMonitorsConfig`, and the user's mid-session changes are polled from
|
||
//! DisplayConfig and written back.
|
||
|
||
use super::{Mode, VirtualDisplay, VirtualOutput};
|
||
use anyhow::{anyhow, bail, Context, Result};
|
||
use ashpd::zbus;
|
||
use futures_util::StreamExt;
|
||
use std::collections::{HashMap, HashSet};
|
||
use std::sync::atomic::{AtomicBool, Ordering};
|
||
use std::sync::mpsc::Sender;
|
||
use std::sync::Arc;
|
||
use std::thread;
|
||
use std::time::{Duration, Instant};
|
||
use zbus::zvariant::{OwnedObjectPath, OwnedValue, Value};
|
||
|
||
const BUS_RD: &str = "org.gnome.Mutter.RemoteDesktop";
|
||
const BUS_SC: &str = "org.gnome.Mutter.ScreenCast";
|
||
const BUS_DC: &str = "org.gnome.Mutter.DisplayConfig";
|
||
/// `ApplyMonitorsConfig` method: 1 = temporary (auto-reverts on the next monitor change —
|
||
/// e.g. when our virtual output is torn down — so we never persist a layout to monitors.xml).
|
||
const APPLY_TEMPORARY: u32 = 1;
|
||
|
||
/// Mutter cursor mode: render the cursor into the stream (matches the KWin/gamescope backends).
|
||
const CURSOR_EMBEDDED: u32 = 1;
|
||
|
||
/// Serializes, process-wide, every Mutter operation that adds/removes a virtual monitor or applies
|
||
/// a monitor configuration. Each of these makes Mutter rebuild its monitor topology, and
|
||
/// *concurrent* rebuilds have segfaulted gnome-shell on-glass twice now: the teardown-side race is
|
||
/// documented at the teardown below, and on 2026-07-10 three simultaneous session setups (three
|
||
/// `RecordVirtual` calls within ~200 µs plus an `ApplyMonitorsConfig`) crashed the shell inside
|
||
/// `meta_monitor_manager_rebuild` — dropping the box to the GDM greeter until a DM restart. One
|
||
/// mutation at a time also keeps [`wait_virtual_connector`] sound: with two virtual outputs
|
||
/// appearing at once, "the connector absent from MY pre-snapshot" can name a sibling's monitor.
|
||
/// Each session runs on its own dedicated thread (see [`session_thread`]), so blocking on a std
|
||
/// mutex — including across the awaits of its single-threaded setup future — is safe.
|
||
static TOPOLOGY_LOCK: std::sync::Mutex<()> = std::sync::Mutex::new(());
|
||
|
||
/// The Mutter virtual-display driver. Each [`create`](VirtualDisplay::create) spins up a
|
||
/// keepalive thread owning the D-Bus sessions behind the virtual monitor.
|
||
pub struct MutterDisplay {
|
||
/// Whether this display is the FIRST of its group (§6.1) — set by the registry before `create`.
|
||
/// A later sibling **extends** into the already-exclusive desktop instead of re-applying the
|
||
/// sole-monitor config (which would disable the first session's virtual). Defaults true (a lone
|
||
/// session establishes topology as before).
|
||
first_in_group: bool,
|
||
/// The connecting client's cert fingerprint (set before [`create`](VirtualDisplay::create)) —
|
||
/// keys the per-client persisted **scale** (GNOME can't persist it itself: Mutter mints a fresh
|
||
/// EDID serial per `RecordVirtual` monitor, so `monitors.xml` never rematches; see
|
||
/// [`identity::ScaleMap`](crate::identity)).
|
||
client_fp: Option<[u8; 32]>,
|
||
/// The identity slot the last `create` resolved — reported to the registry via
|
||
/// [`last_identity_slot`](VirtualDisplay::last_identity_slot) to key the group arrangement +
|
||
/// `/display/state` slot, like the KWin backend.
|
||
last_slot: Option<u32>,
|
||
}
|
||
|
||
impl MutterDisplay {
|
||
pub fn new() -> Result<Self> {
|
||
Ok(MutterDisplay {
|
||
first_in_group: true,
|
||
client_fp: None,
|
||
last_slot: None,
|
||
})
|
||
}
|
||
}
|
||
|
||
/// Mutter is usable when the host runs inside a GNOME session (its `RecordVirtual` D-Bus API
|
||
/// drives the *live* compositor). Cheap signal: `XDG_CURRENT_DESKTOP` names GNOME — same basis
|
||
/// as [`super::detect`], avoiding a blocking D-Bus round-trip on the enumeration path.
|
||
pub fn is_available() -> bool {
|
||
std::env::var("XDG_CURRENT_DESKTOP")
|
||
.map(|d| d.to_ascii_uppercase().contains("GNOME"))
|
||
.unwrap_or(false)
|
||
}
|
||
|
||
impl VirtualDisplay for MutterDisplay {
|
||
fn name(&self) -> &'static str {
|
||
"mutter"
|
||
}
|
||
|
||
fn set_first_in_group(&mut self, first: bool) {
|
||
self.first_in_group = first;
|
||
}
|
||
|
||
fn set_client_identity(&mut self, fingerprint: Option<[u8; 32]>) {
|
||
self.client_fp = fingerprint;
|
||
}
|
||
|
||
fn last_identity_slot(&self) -> Option<u32> {
|
||
self.last_slot
|
||
}
|
||
|
||
fn create(&mut self, mode: Mode) -> Result<VirtualOutput> {
|
||
// Identity (§5.4): resolve the client's stable slot per the `identity` policy (Linux
|
||
// defaults to Shared when unconfigured, like KWin) — it keys the registry's group
|
||
// arrangement/state. Mutter can't carry the slot into the monitor's EDID (RecordVirtual
|
||
// owns the identity), so the per-client scaling that policy promises is host-persisted
|
||
// instead: the session thread reapplies the remembered scale and records the user's
|
||
// in-session changes under `scale_key`.
|
||
self.last_slot = crate::identity::resolve_slot(
|
||
self.client_fp,
|
||
(mode.width, mode.height),
|
||
crate::policy::Identity::Shared,
|
||
);
|
||
let scale_key = crate::identity::scale_key(
|
||
self.client_fp,
|
||
(mode.width, mode.height),
|
||
crate::policy::Identity::Shared,
|
||
);
|
||
let remembered_scale = crate::identity::scales()
|
||
.lock()
|
||
.unwrap()
|
||
.get(&scale_key);
|
||
if let Some(scale) = remembered_scale {
|
||
tracing::info!(scale, "mutter: reapplying the client's saved display scale");
|
||
}
|
||
let (setup_tx, setup_rx) = std::sync::mpsc::channel::<Result<u32, String>>();
|
||
let stop = Arc::new(AtomicBool::new(false));
|
||
let stop_thread = stop.clone();
|
||
let first_in_group = self.first_in_group;
|
||
thread::Builder::new()
|
||
.name("punktfunk-mutter-vout".into())
|
||
.spawn(move || {
|
||
session_thread(
|
||
setup_tx,
|
||
stop_thread,
|
||
mode,
|
||
first_in_group,
|
||
scale_key,
|
||
remembered_scale,
|
||
)
|
||
})
|
||
.context("spawn Mutter virtual-output thread")?;
|
||
|
||
// 45 s (was 20 s): setups now queue on TOPOLOGY_LOCK, so a session behind a slow sibling
|
||
// (whose guard spans up to a ~10 s stream wait + 6 s connector wait + the apply) must
|
||
// outwait it plus its own handshake before this fires.
|
||
let node_id = match setup_rx.recv_timeout(Duration::from_secs(45)) {
|
||
Ok(Ok(v)) => v,
|
||
Ok(Err(e)) => bail!("Mutter virtual monitor failed: {e}"),
|
||
Err(_) => bail!("timed out creating the Mutter virtual monitor"),
|
||
};
|
||
tracing::info!(
|
||
node_id,
|
||
w = mode.width,
|
||
h = mode.height,
|
||
"Mutter virtual monitor ready"
|
||
);
|
||
Ok(VirtualOutput::owned(
|
||
node_id,
|
||
Some((mode.width, mode.height, mode.refresh_hz)),
|
||
Box::new(StopGuard(stop)),
|
||
))
|
||
}
|
||
}
|
||
|
||
/// Dropping this ends the keepalive thread, closing the D-Bus connection — Mutter then tears
|
||
/// the remote-desktop + screencast sessions (and the virtual monitor) down.
|
||
struct StopGuard(Arc<AtomicBool>);
|
||
|
||
impl Drop for StopGuard {
|
||
fn drop(&mut self) {
|
||
self.0.store(true, Ordering::Relaxed);
|
||
}
|
||
}
|
||
|
||
/// Keepalive thread: run the D-Bus handshake on a private tokio runtime, report the PipeWire
|
||
/// node id, then hold the connection until stopped. `first_in_group` gates the topology change (a
|
||
/// non-first sibling extends into the group's already-exclusive desktop instead of re-clobbering it).
|
||
/// `scale_key`/`remembered_scale` carry the per-client persisted scale: reapplied at connect,
|
||
/// and the user's in-session changes are recorded back under the key (GNOME itself can't — see
|
||
/// [`identity::ScaleMap`](crate::identity)).
|
||
// TOPOLOGY_LOCK is deliberately held across the awaits of the setup/teardown sequences: each
|
||
// session owns this dedicated OS thread and its own single-future runtime, so the guard never
|
||
// blocks a shared executor — it blocks exactly the sibling session threads, which is the point
|
||
// (see TOPOLOGY_LOCK).
|
||
#[allow(clippy::await_holding_lock)]
|
||
fn session_thread(
|
||
setup_tx: Sender<Result<u32, String>>,
|
||
stop: Arc<AtomicBool>,
|
||
mode: Mode,
|
||
first_in_group: bool,
|
||
scale_key: String,
|
||
remembered_scale: Option<f64>,
|
||
) {
|
||
let rt = match tokio::runtime::Builder::new_multi_thread()
|
||
.worker_threads(1)
|
||
.enable_all()
|
||
.build()
|
||
{
|
||
Ok(rt) => rt,
|
||
Err(e) => {
|
||
let _ = setup_tx.send(Err(format!("build tokio runtime: {e}")));
|
||
return;
|
||
}
|
||
};
|
||
rt.block_on(async move {
|
||
// The whole setup — pre-snapshot → RecordVirtual → ApplyMonitorsConfig — is one
|
||
// read-modify-write on Mutter's monitor state; hold TOPOLOGY_LOCK across it so concurrent
|
||
// sessions can't interleave rebuilds (gnome-shell SIGSEGV) or poison each other's
|
||
// connector diffs. Released before the keepalive park below.
|
||
let topology_guard = TOPOLOGY_LOCK.lock().unwrap_or_else(|e| e.into_inner());
|
||
// Display-management topology (Stage 2): the console policy's level, resolved to a concrete
|
||
// value. `Extend` leaves the virtual output an extension (no config change); `Primary` makes
|
||
// it the primary monitor but keeps the physicals as secondaries; `Exclusive` makes it the
|
||
// SOLE output (physicals disabled). `Auto` never reaches here — it's resolved upstream.
|
||
use crate::policy::Topology;
|
||
let topo = crate::effective_topology();
|
||
let topo_policy = matches!(topo, Topology::Primary | Topology::Exclusive);
|
||
// Group-aware (§6.1): only the FIRST display of the group establishes the topology. A later
|
||
// sibling extends into the already-exclusive desktop — re-applying the sole-monitor config would
|
||
// disable the first session's virtual output (Mutter connectors are un-nameable, so we can't
|
||
// build a config that keeps all group virtuals; skipping is the safe choice). *Concurrent
|
||
// Mutter exclusive is on-glass-validation-pending; the APPLY_TEMPORARY revert when the FIRST
|
||
// session leaves under a live sibling is a documented residual (design §7).*
|
||
let want_config = first_in_group && topo_policy;
|
||
if topo_policy && !first_in_group {
|
||
tracing::info!(
|
||
"mutter: joining an existing display group — extending (the first session owns the \
|
||
exclusive/primary topology)"
|
||
);
|
||
}
|
||
let exclusive = matches!(topo, Topology::Exclusive);
|
||
// Snapshot the monitor layout BEFORE the virtual output exists — it's how we tell the new
|
||
// connector apart, both for the topology apply and for tracking the scale the user sets on
|
||
// it. Taken unconditionally now (scale tracking wants it even when we won't touch the
|
||
// topology); failure just degrades to no-topology + no-scale-persistence, as before.
|
||
let dc_pre = match display_config().await {
|
||
Ok(dc) => match get_state(&dc).await {
|
||
Ok(state) => Some((dc, state)),
|
||
Err(e) => {
|
||
tracing::warn!(error = %format!("{e:#}"), "mutter: GetCurrentState (pre) failed; topology + scale persistence off");
|
||
None
|
||
}
|
||
},
|
||
Err(e) => {
|
||
tracing::warn!(error = %format!("{e:#}"), "mutter: DisplayConfig unavailable; topology + scale persistence off");
|
||
None
|
||
}
|
||
};
|
||
|
||
let session = match connect(mode, remembered_scale).await {
|
||
Ok(s) => s,
|
||
Err(e) => {
|
||
let _ = setup_tx.send(Err(format!("{e:#}")));
|
||
return;
|
||
}
|
||
};
|
||
let _ = setup_tx.send(Ok(session.node_id));
|
||
|
||
// Identify the virtual connector (present now, absent in the pre-snapshot), then — when this
|
||
// session owns the topology — make it the PRIMARY monitor so the GNOME shell + new windows
|
||
// land on the surface we stream. Without this, on a host that also has a physical monitor
|
||
// attached, the virtual output is an empty extended desktop — you stream only the wallpaper.
|
||
// Best-effort: any failure just logs and streaming continues unchanged.
|
||
let mut tracked: Option<(zbus::Proxy<'static>, CurrentState, String)> = None;
|
||
if let Some((dc, pre)) = dc_pre {
|
||
match wait_virtual_connector(&dc, &pre).await {
|
||
Ok((vconn, state)) => {
|
||
if want_config {
|
||
match make_virtual_primary(
|
||
&dc,
|
||
mode,
|
||
&pre,
|
||
&state,
|
||
&vconn,
|
||
exclusive,
|
||
remembered_scale,
|
||
)
|
||
.await
|
||
{
|
||
Ok(()) => tracing::info!(
|
||
exclusive,
|
||
"mutter: virtual output set as the primary monitor (physicals {})",
|
||
if exclusive { "disabled" } else { "kept" }
|
||
),
|
||
Err(e) => tracing::warn!(
|
||
error = %format!("{e:#}"),
|
||
"mutter: could not set the virtual output primary; streaming continues — the desktop may render on the physical monitor"
|
||
),
|
||
}
|
||
}
|
||
tracked = Some((dc, pre, vconn));
|
||
}
|
||
Err(e) => tracing::warn!(
|
||
error = %format!("{e:#}"),
|
||
"mutter: virtual connector not identified; topology + scale persistence off"
|
||
),
|
||
}
|
||
}
|
||
|
||
drop(topology_guard);
|
||
|
||
// Park, keeping `session` (and its zbus connection) alive until told to stop. Every ~5 s,
|
||
// read the virtual output's logical-monitor scale and persist a change the user made (GNOME
|
||
// Settings mid-stream) under the client's key — polled rather than teardown-only so a host
|
||
// crash/redeploy doesn't lose it.
|
||
let mut known = remembered_scale.unwrap_or(1.0);
|
||
let mut ticks: u32 = 0;
|
||
while !stop.load(Ordering::Relaxed) {
|
||
tokio::time::sleep(Duration::from_millis(200)).await;
|
||
ticks = ticks.wrapping_add(1);
|
||
if ticks % 25 == 0 {
|
||
if let Some((dc, _, vconn)) = &tracked {
|
||
persist_scale_change(dc, vconn, &scale_key, &mut known).await;
|
||
}
|
||
}
|
||
}
|
||
// Final scale read BEFORE Stop (the virtual output must still exist to be read).
|
||
if let Some((dc, _, vconn)) = &tracked {
|
||
persist_scale_change(dc, vconn, &scale_key, &mut known).await;
|
||
}
|
||
|
||
// Tear down: STOP the screencast so Mutter removes the virtual output. We deliberately do NOT
|
||
// re-assert the physical layout with our own ApplyMonitorsConfig. Issuing a monitor reconfig
|
||
// while the just-removed high-refresh virtual output is still tearing down SIGSEGVs gnome-shell
|
||
// on Mutter 50 + NVIDIA — observed live on home-worker-3: the teardown ApplyMonitorsConfig
|
||
// returned "recipient disconnected from message bus" because the shell crashed mid-call, after
|
||
// which GDM's crash-loop guard dropped to the greeter and wedged EVERY subsequent reconnect.
|
||
// make_virtual_primary applied an APPLY_TEMPORARY config; Mutter reverts that on its own once
|
||
// the virtual output disappears and our DisplayConfig connection (in `tracked`) closes — so we
|
||
// just drop it here and let the revert happen Mutter-side, never touching the layout ourselves.
|
||
// The Stop (+ the revert it triggers) is a topology mutation too — take TOPOLOGY_LOCK so a
|
||
// sibling's teardown or setup can't interleave with the rebuild it causes.
|
||
let _topology_guard = TOPOLOGY_LOCK.lock().unwrap_or_else(|e| e.into_inner());
|
||
let _ = session.rd_session.call_method("Stop", &()).await;
|
||
drop(tracked);
|
||
});
|
||
}
|
||
|
||
/// The live session objects (held for the stream's lifetime) + the PipeWire node id.
|
||
struct MutterSession {
|
||
rd_session: zbus::Proxy<'static>,
|
||
_sc_session: zbus::Proxy<'static>,
|
||
_conn: zbus::Connection,
|
||
node_id: u32,
|
||
}
|
||
|
||
/// Run the four-step handshake (see module docs). `preferred_scale` is the client's remembered
|
||
/// desktop scale, passed as the virtual mode's `preferred-scale` so Mutter creates the monitor
|
||
/// already scaled (Mutter ≥ 48; older Mutter ignores unknown mode keys) — this covers the
|
||
/// `extend` topology, where we never issue our own ApplyMonitorsConfig.
|
||
async fn connect(mode: Mode, preferred_scale: Option<f64>) -> Result<MutterSession> {
|
||
let conn = zbus::Connection::session()
|
||
.await
|
||
.context("connect session D-Bus")?;
|
||
|
||
// 1. RemoteDesktop session (the anchor; also the future input path).
|
||
let rd = zbus::Proxy::new(
|
||
&conn,
|
||
BUS_RD,
|
||
"/org/gnome/Mutter/RemoteDesktop",
|
||
"org.gnome.Mutter.RemoteDesktop",
|
||
)
|
||
.await
|
||
.context("RemoteDesktop proxy (is gnome-shell / `gnome-shell --headless` running?)")?;
|
||
let rd_path: OwnedObjectPath = rd
|
||
.call("CreateSession", &())
|
||
.await
|
||
.context("RemoteDesktop.CreateSession")?;
|
||
let rd_session = zbus::Proxy::new(
|
||
&conn,
|
||
BUS_RD,
|
||
rd_path,
|
||
"org.gnome.Mutter.RemoteDesktop.Session",
|
||
)
|
||
.await?;
|
||
let session_id: String = rd_session
|
||
.get_property("SessionId")
|
||
.await
|
||
.context("read SessionId")?;
|
||
|
||
// 2. ScreenCast session anchored to it.
|
||
let sc = zbus::Proxy::new(
|
||
&conn,
|
||
BUS_SC,
|
||
"/org/gnome/Mutter/ScreenCast",
|
||
"org.gnome.Mutter.ScreenCast",
|
||
)
|
||
.await
|
||
.context("ScreenCast proxy")?;
|
||
let mut props: HashMap<&str, Value> = HashMap::new();
|
||
props.insert("remote-desktop-session-id", Value::from(session_id));
|
||
let sc_path: OwnedObjectPath = sc
|
||
.call("CreateSession", &(props,))
|
||
.await
|
||
.context("ScreenCast.CreateSession")?;
|
||
let sc_session = zbus::Proxy::new(
|
||
&conn,
|
||
BUS_SC,
|
||
sc_path,
|
||
"org.gnome.Mutter.ScreenCast.Session",
|
||
)
|
||
.await?;
|
||
|
||
// 3. The virtual monitor. For >60 Hz we pin the client's exact WxH@Hz via RecordVirtual's
|
||
// "modes" (explicit size + refresh-rate; Mutter ≥ 47) — validated at 5120×1440@240 on Mutter 50
|
||
// + NVIDIA. At ≤60 Hz we let Mutter derive the refresh from the PipeWire framerate (its 60 Hz
|
||
// default is already correct), so the custom-mode path only runs when it buys something.
|
||
// (A high-refresh virtual CRTC used to SIGSEGV gnome-shell on teardown, which is why this was
|
||
// once gated behind PUNKTFUNK_MUTTER_VIRTUAL_REFRESH; the stop-screencast-before-any-monitor-
|
||
// reconfig teardown below fixed the crash, so pinning the client's refresh is now the default.)
|
||
let mut rec: HashMap<&str, Value> = HashMap::new();
|
||
rec.insert("cursor-mode", Value::from(CURSOR_EMBEDDED));
|
||
if mode.refresh_hz > 60 || preferred_scale.is_some() {
|
||
let mut vmode: HashMap<&str, Value> = HashMap::new();
|
||
vmode.insert("size", Value::from((mode.width, mode.height)));
|
||
// Only pin the refresh when it buys something (see above) — a remembered scale alone
|
||
// rides Mutter's 60 Hz default, exactly like the no-modes path did.
|
||
if mode.refresh_hz > 60 {
|
||
vmode.insert("refresh-rate", Value::from(mode.refresh_hz as f64));
|
||
}
|
||
if let Some(scale) = preferred_scale {
|
||
vmode.insert("preferred-scale", Value::from(scale));
|
||
}
|
||
vmode.insert("is-preferred", Value::from(true));
|
||
rec.insert("modes", Value::from(vec![vmode]));
|
||
}
|
||
let stream_path: OwnedObjectPath = sc_session
|
||
.call("RecordVirtual", &(rec,))
|
||
.await
|
||
.context("Session.RecordVirtual")?;
|
||
let stream = zbus::Proxy::new(
|
||
&conn,
|
||
BUS_SC,
|
||
stream_path,
|
||
"org.gnome.Mutter.ScreenCast.Stream",
|
||
)
|
||
.await?;
|
||
|
||
// 4. Subscribe to the node-id signal BEFORE starting, then start the (combined) session.
|
||
let mut added = stream
|
||
.receive_signal("PipeWireStreamAdded")
|
||
.await
|
||
.context("subscribe PipeWireStreamAdded")?;
|
||
rd_session
|
||
.call_method("Start", &())
|
||
.await
|
||
.context("RemoteDesktop.Session.Start")?;
|
||
let msg = tokio::time::timeout(Duration::from_secs(10), added.next())
|
||
.await
|
||
.map_err(|_| anyhow!("PipeWireStreamAdded did not arrive within 10s"))?
|
||
.ok_or_else(|| anyhow!("signal stream ended before PipeWireStreamAdded"))?;
|
||
let (node_id,): (u32,) = msg
|
||
.body()
|
||
.deserialize()
|
||
.context("PipeWireStreamAdded body")?;
|
||
|
||
Ok(MutterSession {
|
||
rd_session,
|
||
_sc_session: sc_session,
|
||
_conn: conn,
|
||
node_id,
|
||
})
|
||
}
|
||
|
||
// ---------------------------------------------------------------------------------------------
|
||
// Optional: make the per-session virtual output the PRIMARY monitor (PUNKTFUNK_MUTTER_VIRTUAL_PRIMARY).
|
||
//
|
||
// `RecordVirtual` adds the virtual monitor as an *extended* desktop. On a headless host that's the
|
||
// only display, so the shell + windows live there. But when a physical monitor is attached, GNOME
|
||
// keeps it primary and the virtual output is an empty extension — the stream shows only the
|
||
// wallpaper. We fix that by promoting the virtual output to primary (physical kept on, secondary)
|
||
// via `org.gnome.Mutter.DisplayConfig.ApplyMonitorsConfig`, and restore on teardown.
|
||
// ---------------------------------------------------------------------------------------------
|
||
|
||
/// `org.gnome.Mutter.DisplayConfig.GetCurrentState` reply shapes (see the interface XML):
|
||
/// monitors: `a((ssss)a(siiddada{sv})a{sv})`
|
||
/// logical_monitors: `a(iiduba(ssss)a{sv})`
|
||
type MonitorSpec = (String, String, String, String); // connector, vendor, product, serial
|
||
type DbusMode = (
|
||
String,
|
||
i32,
|
||
i32,
|
||
f64,
|
||
f64,
|
||
Vec<f64>,
|
||
HashMap<String, OwnedValue>,
|
||
);
|
||
type MonitorInfo = (MonitorSpec, Vec<DbusMode>, HashMap<String, OwnedValue>);
|
||
type LogicalMonitor = (
|
||
i32,
|
||
i32,
|
||
f64,
|
||
u32,
|
||
bool,
|
||
Vec<MonitorSpec>,
|
||
HashMap<String, OwnedValue>,
|
||
);
|
||
type CurrentState = (
|
||
u32,
|
||
Vec<MonitorInfo>,
|
||
Vec<LogicalMonitor>,
|
||
HashMap<String, OwnedValue>,
|
||
);
|
||
|
||
/// `ApplyMonitorsConfig` logical-monitor shape: `(iiduba(ssa{sv}))`, monitor = `(ssa{sv})`.
|
||
type ApplyMon = (String, String, HashMap<String, Value<'static>>); // connector, mode_id, props
|
||
type ApplyLogical = (i32, i32, f64, u32, bool, Vec<ApplyMon>);
|
||
|
||
/// A DisplayConfig proxy on its own session-bus connection (owned, so it stays alive for the
|
||
/// session — independent of the RemoteDesktop/ScreenCast connection).
|
||
async fn display_config() -> Result<zbus::Proxy<'static>> {
|
||
let conn = zbus::Connection::session()
|
||
.await
|
||
.context("connect session D-Bus (DisplayConfig)")?;
|
||
zbus::Proxy::new(
|
||
&conn,
|
||
BUS_DC,
|
||
"/org/gnome/Mutter/DisplayConfig",
|
||
"org.gnome.Mutter.DisplayConfig",
|
||
)
|
||
.await
|
||
.context("DisplayConfig proxy")
|
||
}
|
||
|
||
async fn get_state(dc: &zbus::Proxy<'_>) -> Result<CurrentState> {
|
||
dc.call("GetCurrentState", &())
|
||
.await
|
||
.context("DisplayConfig.GetCurrentState")
|
||
}
|
||
|
||
fn connectors(state: &CurrentState) -> HashSet<String> {
|
||
state.1.iter().map(|m| m.0 .0.clone()).collect()
|
||
}
|
||
|
||
fn mode_flag(md: &DbusMode, key: &str) -> bool {
|
||
matches!(md.6.get(key).map(|v| &**v), Some(&Value::Bool(true)))
|
||
}
|
||
|
||
/// The current (else preferred, else first) mode of `connector` → `(mode_id, width, height, refresh)`.
|
||
fn current_mode_full(state: &CurrentState, connector: &str) -> Option<(String, i32, i32, f64)> {
|
||
let mon = state.1.iter().find(|m| m.0 .0 == connector)?;
|
||
let pick = mon
|
||
.1
|
||
.iter()
|
||
.find(|md| mode_flag(md, "is-current"))
|
||
.or_else(|| mon.1.iter().find(|md| mode_flag(md, "is-preferred")))
|
||
.or_else(|| mon.1.first())?;
|
||
Some((pick.0.clone(), pick.1, pick.2, pick.3))
|
||
}
|
||
|
||
/// As [`current_mode_full`] but dropping the refresh (callers that only place by width).
|
||
fn current_mode(state: &CurrentState, connector: &str) -> Option<(String, i32, i32)> {
|
||
current_mode_full(state, connector).map(|(id, w, h, _)| (id, w, h))
|
||
}
|
||
|
||
/// Pure mode-pick for a KEPT physical (unit-tested). Given the physical's PRE-connect mode
|
||
/// (`pre_mode = (id, w, h, refresh)`; `None` when the connector is new since the snapshot) and the
|
||
/// mode list Mutter reports for it in the POST-virtual state
|
||
/// (`(id, w, h, refresh, is_current, is_preferred)`), return the `(mode_id, width)` to re-apply.
|
||
///
|
||
/// Mutter re-derives its layout when the `RecordVirtual` output appears and can silently drop a
|
||
/// 120 Hz panel to its EDID-preferred 60 Hz — so the post-virtual `is-current` is *already* 60 Hz.
|
||
/// We therefore prefer the PRE mode (its real refresh), resolved to a mode id valid at apply time;
|
||
/// only when the physical genuinely no longer offers that mode do we fall back to the post-virtual
|
||
/// current (never inventing a mode id `ApplyMonitorsConfig` would reject).
|
||
fn pick_keep_mode(
|
||
pre_mode: Option<(String, i32, i32, f64)>,
|
||
state_modes: &[(String, i32, i32, f64, bool, bool)],
|
||
) -> Option<(String, i32)> {
|
||
let state_current = || {
|
||
state_modes
|
||
.iter()
|
||
.find(|m| m.4)
|
||
.or_else(|| state_modes.iter().find(|m| m.5))
|
||
.or_else(|| state_modes.first())
|
||
.map(|m| (m.0.clone(), m.1))
|
||
};
|
||
let Some((pre_id, w, h, hz)) = pre_mode else {
|
||
return state_current();
|
||
};
|
||
// The exact pre mode id, if the connector still offers it (same session ⇒ usually true).
|
||
if state_modes.iter().any(|m| m.0 == pre_id) {
|
||
return Some((pre_id, w));
|
||
}
|
||
// Else a re-keyed id with the same geometry + refresh (still the real 120 Hz).
|
||
if let Some(m) = state_modes
|
||
.iter()
|
||
.find(|m| m.1 == w && m.2 == h && (m.3 - hz).abs() < 0.5)
|
||
{
|
||
return Some((m.0.clone(), m.1));
|
||
}
|
||
// The physical genuinely no longer offers that mode — use whatever is valid now.
|
||
state_current()
|
||
}
|
||
|
||
/// The `(mode_id, width)` a kept physical should be RE-APPLIED at — its PRE-connect mode preserved
|
||
/// across Mutter's virtual-output layout re-derive. See [`pick_keep_mode`].
|
||
fn physical_keep_mode(
|
||
pre: &CurrentState,
|
||
state: &CurrentState,
|
||
conn: &str,
|
||
) -> Option<(String, i32)> {
|
||
let pre_mode = current_mode_full(pre, conn);
|
||
let state_modes: Vec<(String, i32, i32, f64, bool, bool)> = state
|
||
.1
|
||
.iter()
|
||
.find(|m| m.0 .0 == conn)
|
||
.map(|mon| {
|
||
mon.1
|
||
.iter()
|
||
.map(|md| {
|
||
(
|
||
md.0.clone(),
|
||
md.1,
|
||
md.2,
|
||
md.3,
|
||
mode_flag(md, "is-current"),
|
||
mode_flag(md, "is-preferred"),
|
||
)
|
||
})
|
||
.collect()
|
||
})
|
||
.unwrap_or_default();
|
||
pick_keep_mode(pre_mode, &state_modes)
|
||
}
|
||
|
||
/// Wait for the virtual output to appear in DisplayConfig (its size follows PipeWire negotiation,
|
||
/// which lands shortly after the node id) and return its connector name (present now, absent in
|
||
/// the pre-snapshot) plus the state that contained it.
|
||
async fn wait_virtual_connector(
|
||
dc: &zbus::Proxy<'_>,
|
||
pre: &CurrentState,
|
||
) -> Result<(String, CurrentState)> {
|
||
let pre_conns = connectors(pre);
|
||
let deadline = Instant::now() + Duration::from_secs(6);
|
||
loop {
|
||
let state = get_state(dc).await?;
|
||
let virt = state
|
||
.1
|
||
.iter()
|
||
.map(|m| m.0 .0.clone())
|
||
.find(|c| !pre_conns.contains(c));
|
||
if let Some(vconn) = virt {
|
||
return Ok((vconn, state));
|
||
}
|
||
if Instant::now() >= deadline {
|
||
bail!("the virtual monitor did not appear in DisplayConfig within 6s");
|
||
}
|
||
tokio::time::sleep(Duration::from_millis(250)).await;
|
||
}
|
||
}
|
||
|
||
/// Make the virtual output the primary output — SOLE (`exclusive`: physicals disabled for the
|
||
/// session) or with the physicals kept as secondaries — so the cursor, windows, and keyboard focus
|
||
/// stay on the streamed surface. Applied at the client's `remembered_scale` (validated against the
|
||
/// mode's supported scales; 1.0 when none is remembered) so a saved DPI setting survives the
|
||
/// reconnect. Reverted by Mutter on teardown (APPLY_TEMPORARY).
|
||
async fn make_virtual_primary(
|
||
dc: &zbus::Proxy<'_>,
|
||
mode: Mode,
|
||
pre: &CurrentState,
|
||
state: &CurrentState,
|
||
vconn: &str,
|
||
exclusive: bool,
|
||
remembered_scale: Option<f64>,
|
||
) -> Result<()> {
|
||
// Prefer the mode matching the client's WxH; fall back to whatever is current.
|
||
let vmode = state
|
||
.1
|
||
.iter()
|
||
.find(|m| m.0 .0 == vconn)
|
||
.and_then(|m| {
|
||
m.1.iter()
|
||
.find(|md| md.1 == mode.width as i32 && md.2 == mode.height as i32)
|
||
.map(|md| md.0.clone())
|
||
})
|
||
.or_else(|| current_mode(state, vconn).map(|(id, _, _)| id));
|
||
let Some(vmode) = vmode else {
|
||
bail!("virtual monitor {vconn} has no usable mode yet");
|
||
};
|
||
// The scale to apply. Mutter (≥ its `preferred-scale` support) already derived the virtual's
|
||
// logical monitor at the remembered scale we passed to RecordVirtual, PRE-VALIDATED — preserve
|
||
// that instead of forcing a value (forcing 1.0 here was the original scale-clobber bug). On an
|
||
// older Mutter the derived scale stays 1.0 while a scale is remembered — try the remembered
|
||
// value snapped to an integral logical size (Mutter's fractional-scaling validity rule;
|
||
// GetCurrentState reports NO supported-scales for virtual monitors to snap to), and retry at
|
||
// the derived scale if the whole apply is rejected (an invalid scale fails the entire config —
|
||
// losing the primary switch over scaling would be worse).
|
||
let derived = logical_scale(state, vconn)
|
||
.filter(|s| s.is_finite() && *s > 0.0)
|
||
.unwrap_or(1.0);
|
||
let mut scale = match remembered_scale {
|
||
Some(want) if (want - derived).abs() > 1e-3 => {
|
||
snap_integral_scale(want, mode.width, mode.height)
|
||
}
|
||
_ => derived,
|
||
};
|
||
loop {
|
||
// Exclusive: the virtual output alone (physicals omitted → Mutter disables them).
|
||
// Primary: the virtual output primary at (0,0) PLUS the physicals kept as secondaries.
|
||
// (On a headless host with no physicals the two are identical.)
|
||
let config = if exclusive {
|
||
build_exclusive_config(vconn, &vmode, scale)
|
||
} else {
|
||
build_primary_keeping_physicals(pre, state, vconn, &vmode, mode.width as i32, scale)
|
||
};
|
||
let res: zbus::Result<()> = dc
|
||
.call(
|
||
"ApplyMonitorsConfig",
|
||
&(
|
||
state.0,
|
||
APPLY_TEMPORARY,
|
||
config,
|
||
HashMap::<String, Value<'static>>::new(),
|
||
),
|
||
)
|
||
.await;
|
||
match res {
|
||
Ok(()) => return Ok(()),
|
||
Err(e) if (scale - derived).abs() > 1e-3 => {
|
||
tracing::warn!(
|
||
scale,
|
||
derived,
|
||
error = %format!("{e:#}"),
|
||
"mutter: ApplyMonitorsConfig at the remembered scale failed — retrying at the derived scale"
|
||
);
|
||
scale = derived;
|
||
}
|
||
Err(e) => {
|
||
return Err(e).context("DisplayConfig.ApplyMonitorsConfig (set virtual primary)")
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Snap `want` to the nearest scale that gives the mode an **integral logical size** — Mutter only
|
||
/// accepts fractional scales where both `width/scale` and `height/scale` are integers, and its
|
||
/// GetCurrentState reports no `supported-scales` for virtual monitors to snap to. Searches the few
|
||
/// logical widths around the target for one that keeps the aspect exact; falls back to `want`
|
||
/// unchanged (the caller retries at the derived scale if Mutter still rejects it). Pure, unit-tested.
|
||
fn snap_integral_scale(want: f64, width: u32, height: u32) -> f64 {
|
||
if !want.is_finite() || want <= 0.0 {
|
||
return 1.0;
|
||
}
|
||
let (w, h) = (width as i64, height as i64);
|
||
let target = (w as f64 / want).round() as i64;
|
||
(target - 8..=target + 8)
|
||
.filter(|lw| *lw >= 1 && (h * lw) % w == 0)
|
||
.map(|lw| w as f64 / lw as f64)
|
||
.min_by(|a, b| (a - want).abs().total_cmp(&(b - want).abs()))
|
||
.unwrap_or(want)
|
||
}
|
||
|
||
/// The scale of the logical monitor carrying `connector`, if present.
|
||
fn logical_scale(state: &CurrentState, connector: &str) -> Option<f64> {
|
||
state
|
||
.2
|
||
.iter()
|
||
.find(|l| l.5.iter().any(|spec| spec.0 == connector))
|
||
.map(|l| l.2)
|
||
}
|
||
|
||
/// Read the virtual output's current scale and, when the user changed it (GNOME Settings
|
||
/// mid-stream), persist it under the client's `scale_key` so the next connect reapplies it.
|
||
/// Best-effort: read failures (teardown races, shell restart) are silently skipped.
|
||
async fn persist_scale_change(dc: &zbus::Proxy<'_>, vconn: &str, scale_key: &str, known: &mut f64) {
|
||
let Ok(state) = get_state(dc).await else {
|
||
return;
|
||
};
|
||
let Some(cur) = logical_scale(&state, vconn) else {
|
||
return;
|
||
};
|
||
if (cur - *known).abs() > 1e-3 {
|
||
crate::identity::scales()
|
||
.lock()
|
||
.unwrap()
|
||
.set(scale_key, cur);
|
||
*known = cur;
|
||
tracing::info!(
|
||
scale = cur,
|
||
"mutter: persisted the client's display scale for the next connect"
|
||
);
|
||
}
|
||
}
|
||
|
||
/// **Exclusive** — the virtual output as the SOLE, primary monitor: physical outputs are omitted, so
|
||
/// Mutter disables them for the session. This confines the cursor, windows, and keyboard focus to the
|
||
/// streamed surface; keeping the physical enabled as a *secondary* monitor instead lets relative
|
||
/// pointer motion and window focus wander onto it (invisible to the client — the cursor seems to
|
||
/// vanish). The physical layout is restored on teardown.
|
||
fn build_exclusive_config(vconn: &str, vmode: &str, scale: f64) -> Vec<ApplyLogical> {
|
||
vec![(
|
||
0,
|
||
0,
|
||
scale,
|
||
0,
|
||
true,
|
||
vec![(vconn.to_string(), vmode.to_string(), HashMap::new())],
|
||
)]
|
||
}
|
||
|
||
/// **Primary** — the virtual output primary at `(0, 0)`, with every currently-active physical
|
||
/// monitor KEPT as a secondary (laid left-to-right past the virtual, each at its **pre-connect**
|
||
/// mode). So the shell + new windows land on the streamed surface, but the operator's physical
|
||
/// screen stays on **at its real refresh**. On a headless host (no physicals) this is identical to
|
||
/// [`build_exclusive_config`].
|
||
///
|
||
/// `pre` is the snapshot taken *before* the virtual output existed (physical still at its true
|
||
/// refresh); `state` is the post-virtual state. We read each physical's mode from `pre` because
|
||
/// Mutter can knock a 120 Hz panel down to 60 Hz when it re-derives the layout for the virtual
|
||
/// monitor — reading `state` would cement that 60 Hz (`physical_keep_mode`).
|
||
///
|
||
/// *Physical-keep is unvalidated on-glass* — the lab boxes are headless (no attached display to keep
|
||
/// on); the layout math is conservative (append to the right) but wants a display-attached box.
|
||
fn build_primary_keeping_physicals(
|
||
pre: &CurrentState,
|
||
state: &CurrentState,
|
||
vconn: &str,
|
||
vmode: &str,
|
||
virt_width: i32,
|
||
scale: f64,
|
||
) -> Vec<ApplyLogical> {
|
||
let mut logicals: Vec<ApplyLogical> = vec![(
|
||
0,
|
||
0,
|
||
scale,
|
||
0,
|
||
true,
|
||
vec![(vconn.to_string(), vmode.to_string(), HashMap::new())],
|
||
)];
|
||
// Append each physical (non-virtual) connector that has a usable mode, to the right of the
|
||
// virtual output, as a non-primary secondary — at its PRE-connect mode (real refresh preserved).
|
||
// Offsets are in the layout's coordinate space: LOGICAL pixels by default on Wayland (the
|
||
// virtual's footprint is width/scale), physical pixels only under layout-mode 2.
|
||
let physical_layout = matches!(
|
||
state.3.get("layout-mode").map(|v| &**v),
|
||
Some(&Value::U32(2))
|
||
);
|
||
let virt_logical_width = if physical_layout {
|
||
virt_width
|
||
} else {
|
||
((virt_width as f64 / scale).round() as i32).max(1)
|
||
};
|
||
let mut x = virt_logical_width.max(0);
|
||
for mon in &state.1 {
|
||
let conn = &mon.0 .0;
|
||
if conn == vconn {
|
||
continue;
|
||
}
|
||
if let Some((mode_id, w)) = physical_keep_mode(pre, state, conn) {
|
||
logicals.push((
|
||
x,
|
||
0,
|
||
1.0,
|
||
0,
|
||
false,
|
||
vec![(conn.clone(), mode_id, HashMap::new())],
|
||
));
|
||
x += w.max(0);
|
||
}
|
||
}
|
||
logicals
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod tests {
|
||
use super::{pick_keep_mode, snap_integral_scale};
|
||
|
||
// (id, w, h, refresh, is_current, is_preferred)
|
||
fn m(
|
||
id: &str,
|
||
w: i32,
|
||
h: i32,
|
||
hz: f64,
|
||
cur: bool,
|
||
pref: bool,
|
||
) -> (String, i32, i32, f64, bool, bool) {
|
||
(id.to_string(), w, h, hz, cur, pref)
|
||
}
|
||
|
||
#[test]
|
||
fn keep_mode_prefers_pre_refresh_over_downgraded_state() {
|
||
// Physical was 2560x1440@120 pre-connect; after the virtual appeared Mutter marked 60 Hz
|
||
// current (the reported bug). We must re-apply the 120 Hz mode, not the state's 60 Hz.
|
||
let pre = Some(("M120".to_string(), 2560, 1440, 120.0));
|
||
let state = vec![
|
||
m("M120", 2560, 1440, 120.0, false, false),
|
||
m("M60", 2560, 1440, 60.0, true, true),
|
||
];
|
||
assert_eq!(
|
||
pick_keep_mode(pre, &state),
|
||
Some(("M120".to_string(), 2560))
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn keep_mode_rekeyed_id_matches_by_geometry_and_refresh() {
|
||
// The pre id is no longer offered (Mutter re-keyed the mode list), but a 120 Hz mode of the
|
||
// same geometry exists — match it so the real refresh survives.
|
||
let pre = Some(("old-120".to_string(), 2560, 1440, 120.0));
|
||
let state = vec![
|
||
m("new-120", 2560, 1440, 119.998, false, false),
|
||
m("new-60", 2560, 1440, 60.0, true, true),
|
||
];
|
||
assert_eq!(
|
||
pick_keep_mode(pre, &state),
|
||
Some(("new-120".to_string(), 2560))
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn keep_mode_falls_back_to_state_current_when_pre_mode_gone() {
|
||
// The physical genuinely no longer offers its pre mode (e.g. cable renegotiated to a lower
|
||
// max) — never invent an id; use the post-virtual current.
|
||
let pre = Some(("gone-165".to_string(), 3440, 1440, 165.0));
|
||
let state = vec![
|
||
m("s-100", 3440, 1440, 100.0, true, false),
|
||
m("s-60", 3440, 1440, 60.0, false, true),
|
||
];
|
||
assert_eq!(
|
||
pick_keep_mode(pre, &state),
|
||
Some(("s-100".to_string(), 3440))
|
||
);
|
||
}
|
||
|
||
#[test]
|
||
fn snap_integral_scale_keeps_valid_scales_and_snaps_odd_ones() {
|
||
// Already-integral scales survive exactly: 1920/1.5 = 1280, 1080/1.5 = 720.
|
||
assert_eq!(snap_integral_scale(1.5, 1920, 1080), 1.5);
|
||
// The GNOME fractional 1.6666… on 3840x2400 (logical 2304x1440) survives.
|
||
let s = snap_integral_scale(1.666_666_6, 3840, 2400);
|
||
assert!((s - 3840.0 / 2304.0).abs() < 1e-9, "got {s}");
|
||
// A scale with no integral logical size nearby snaps to the closest one that has it:
|
||
// 16:9 logical widths must be multiples of 16 → 1.3 snaps to 1920/1472.
|
||
let s = snap_integral_scale(1.3, 1920, 1080);
|
||
assert!((s - 1920.0 / 1472.0).abs() < 1e-9, "got {s}");
|
||
// Junk input degrades to 1.0.
|
||
assert_eq!(snap_integral_scale(f64::NAN, 1920, 1080), 1.0);
|
||
assert_eq!(snap_integral_scale(-2.0, 1920, 1080), 1.0);
|
||
}
|
||
|
||
#[test]
|
||
fn keep_mode_no_pre_uses_state_current_then_preferred() {
|
||
// A connector new since the pre-snapshot (no pre mode): is-current wins, else is-preferred.
|
||
let state = vec![
|
||
m("A", 1920, 1080, 60.0, true, false),
|
||
m("B", 1920, 1080, 144.0, false, true),
|
||
];
|
||
assert_eq!(pick_keep_mode(None, &state), Some(("A".to_string(), 1920)));
|
||
|
||
let no_current = vec![
|
||
m("A", 1920, 1080, 60.0, false, false),
|
||
m("B", 1920, 1080, 144.0, false, true),
|
||
];
|
||
assert_eq!(
|
||
pick_keep_mode(None, &no_current),
|
||
Some(("B".to_string(), 1920))
|
||
);
|
||
}
|
||
}
|