The compositor was built with its frame-generation leg stubbed out. Bannerlator's
two engines and the DXBC translator they need now ride along, so extra frames
are generated on gamescope's final output — any game, nothing changed in the
runtime. Win-FG needs nothing; LSFG takes its shader chain from the user's own
Lossless Scaling, which in this app is installed from the Steam client and read
straight out of the runtime's library. One picker on the main screen: Off, or an
engine at 2x/3x/4x, applied live on the next return to the session.
The compositor lives for the whole process, so the second Play after a session
had ended re-attached the Surface, started nothing, and left the loading panel
counting up over a dead session — it looked like a login that never came. The
service now starts whenever no session is running; the compositor's one-shot
first-frame notice is re-armed for the new session, or the panel would never
leave; and whatever the previous session left behind (gamescopereaper, the
session script, a dead client's helpers, the audio server) is killed first,
since it is our uid and still holds the socket the new one needs.
The session now belongs to a foreground service rather than the activity.
Android demotes a process as soon as its last visible activity goes and the
low-memory killer reaps the guest, so leaving Big Picture to answer a message
came back to a dead Steam; the service holds the process at perceptible
priority, a partial wake lock keeps the CPU from dropping the guest's threads,
and a high-performance WiFi lock keeps a backgrounded download from being
throttled to nothing. The notification is silent (IMPORTANCE_LOW), carries a
Stop action, and returns to the session when tapped. Back now puts the app away
and leaves Steam running; a swipe out of recents ends the session.
The compositor moved with it: it is process-wide, started once, and merely
swaps the Surface it presents into as the activity comes and goes.
Package is com.steamdeck.launcher, signed with the AOSP testkey (v1+v2+v3) so
every build installs over the last one, and CI asserts all three schemes.
The launcher icon is our own controller on a purple glow — the spirit of the
Steam tile the client entry uses, none of its geometry.
Lifts Bannerlator's Linux/gamescope runtime out into an app of its own: the
Wayland compositor, the proot session, the runtime installer, the fake-evdev
controller path and the PulseAudio server, with none of the Wine, container or
store machinery around them.
One activity installs the runtime from the same winlator-contents catalog and a
second one runs the session: compositor on a SurfaceView, gamescope and Valve's
native arm64 client under proot, a physical pad republished into the fake-input
rings, and the session's milestones on screen until the first frame arrives.
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