DroidDeck/tools/gamescope/PATCHES.md

gamescope patches carried by the app

Built by .github/workflows/build-gamescope.yml on top of the exact gamescope the Linux runtime ships (3.16.29, Arch Linux ARM's package, same build options), and staged from the apk over /usr/local/bin/gamescope at each session start - the hosted runtime image is never touched. The binary's shared-library needs are checked against runtime-sonames.txt, the runtime's own library list, before anything is published.

• 0002-steamcompmgr-fallback-appid-focus.patch - Armada (armada-os/armada), verbatim.
• 0009-fix-arm64-steam-night-mode.patch - Armada, verbatim: the ARM64 client packs the night-mode property differently; the slider did nothing.
• 0019-steamcompmgr-arm64-virtual-white.patch - Armada, verbatim: the colour-temperature slider's (x, y) arrives as one 64-bit element from the ARM64 client; y is recovered from x.
• 0020-color-p3-red-is-wide-gamut.patch - Armada, verbatim.
• 0100-realtime-queue-and-gamepad-cursor.patch - this app, two of Armada's ported by hand onto 3.16.29: realtime-priority Vulkan queues on request (GAMESCOPE_FORCE_VULKAN_REALTIME=1) without CAP_SYS_NICE, which proot can never have (a no-op on KGSL Turnip, which has a single submit-queue priority); and the gamepad-driven cursor sprite following the X pointer that XTest moves (it sat frozen). The X pointer is asked for only while a cursor image is drawn - every vblank while shown, every 50 ms while hidden for inactivity - since each ask is a blocking round trip to Xwayland on the paint thread; with no image, wlserver's position is used as upstream does.
• 0101-nested-wayland-cursor-routing.patch - this app: gamescope_cursor_composite=2 lets the nested Wayland session paint its cursor in the output using the real X pointer position; client cursor surfaces are cleared to prevent a duplicate at the host pointer, while Gamescope's original default host-cursor fallback is preserved when its no-keyboard-focus policy selects it. Empty client cursor images and Gamescope's hidden flag still suppress the painted cursor.
• 0110-wayland-backend-touch.patch - this app: the nested Wayland backend bound only the host's pointer and keyboard, so a finger on the phone's screen never reached Steam. It now binds wl_touch too and hands each finger to wlserver's touch path (wlserver_touchdown / motion / up) - the one a Steam Deck's touchscreen drives - so what a touch does follows the client's touch mode (Steam's Big Picture sets Passthrough: a real touch, rows scroll under a finger). Finger ids are offset by one, since the nested pointer already moves wlserver's touch 0.
• 0111-wayland-pointer-warps-in-passthrough.patch - this app: the nested pointer's motion goes to wlserver as touch 0, and in Passthrough (Big Picture's touch mode) a motion for a touch that is not down moves nothing - so in the app's touchpad mode the Steam client saw no hover and a click landed wherever the pointer had last been. The motion now always warps the real pointer as well (bAlwaysWarpCursor), which the other touch modes did already.
• 0112-restore-iconified-game-on-resume.patch - this app: the Steam menu is an overlay that takes input without changing the focus window, and a fullscreen wine game minimizes itself when it loses input. gamescope only takes a window out of iconic when the focus window changes, and wine will not activate a window it believes iconic, so after Resume the game stayed minimized: a black screen with its small caption in the top-left corner (Titanfall 2, GE-Proton 11). The iconify request is remembered and the window goes back to NormalState before input returns to it, then focus is handed over again. GAMESCOPE_RESTORE_FOCUS_WINDOW on the root window asks for the same restore from outside (the session script's resume watcher).
• 0114-take-override-redirect-from-mapnotify.patch - upstream (ValveSoftware/gamescope 3829340), verbatim; drop it once the runtime's gamescope includes it. Wine creates a game's window override-redirect and makes it managed before mapping it, which sends no X event. When gamescope read the window's attributes first, it kept the window as override-redirect and left it out of GAMESCOPE_FOCUSABLE_WINDOWS, so the client kept its loading screen over the running game (Skyrim SE, A Plague Tale: Innocence, on the games' own Xwayland). MapNotify now refreshes the flag.
• 0115-limiter-paces-per-window.patch - this app: on a fixed-refresh output the frame limiter (Steam's Frame Limit) let a capped window's frames out only on every Nth refresh of a global grid, so a frame finished just after its slot waited a whole extra slot. At 30 on 60 Hz one picture was held for three or four refreshes - "small stops and ladders" with frame generation - where a game's own limiter slips such a frame by one refresh. The fixed-refresh branch now paces each window by time, as the VRR branch already did: its next frame goes out on the first refresh a capped interval after its last one, with half a refresh of tolerance so an on-time window keeps every Nth refresh.
• 0116-hold-overlay-repaint-for-next-frame.patch - this app: on a fixed-refresh output every mangoapp commit asked for a repaint of its own, and mangoapp draws once per game frame just after that frame was shown, so a 60 fps game on a 120 Hz panel was composited twice per frame - 75 frames a second reached the screen, one in two 8 ms after the last with no new picture (Valheim, Stardew Valley, Among Us). The VRR path already leaves such repaints to the next game frame; on a fixed refresh output they now wait for it too, for at most external_overlay_hold_cycles refreshes (4, so 30 fps at 120 Hz still merges), and are painted on their own after that.

Sixteen more of Armada's patches are DRM/lease/HDR-on-KMS work for a native display, which this app's Wayland-hosted gamescope never reaches, or need a newer gamescope than the runtime has.

• 0116-release-cursor-shm-buffers.patch - this app: pointer cursor surfaces have no X11/xdg window association, so routing their commits through g_PendingCommits retained every old SHM buffer until the surface was destroyed. Ignore cursor-role commits before taking the buffer lock; X11 cursor images still follow the existing MouseCursor path. Window commits awaiting association are unchanged.

The live regression probe is tools/tests/test_gamescope_cursor_shm.py. Run it inside an active Gamescope session with access to that process's /proc fd directory. It submits 20 distinct SHM cursor buffers and requires at most the current buffer to remain open, then none after surface destruction. The --unassigned-control variant omits the cursor role and verifies that all 20 commits awaiting a window association remain queued until surface destruction.

Device validation (2026-10-20): the stock component retained 20/20 cursor buffers; the patched component retained 1/20, then 0 after destruction. The unassigned control retained 20/20 and then 0. In Backpack Battles, two batches of ten touch drags leaked 188 and 197 SHM descriptors before the fix; the same batches added zero after the fix (112 total descriptors before and after each batch).

0117 WSI: cache the present-time Xwayland bypass check

QueuePresentKHR in the WSI layer calls canBypassXWayland for every swapchain on every present. Each call makes several synchronous X requests (window geometry, _WINE_ALLOW_FLIP, parent window, a child-window scan, the toplevel window). At high frame rates that is thousands of round trips a second: on an AYANEO Pocket FIT running AIO Graphics Test uncapped, Xwayland used 24-32% of a core and the game's present thread sat about half idle.

The patch can keep the result for DROIDDECK_WSI_BYPASS_CHECK_MS milliseconds. Unset or 0 keeps the per-present check; the app sets 100 only in Performance mode and 0 otherwise. With 100, a window resize or a flip/obscure change is seen up to 100 ms later than before; surface creation and capability queries still check every time.