fix(flatpak): Deck HDR works on a plain install #64

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enricobuehler merged 2 commits from worktree-deck-hdr-wsi-env into main 2026-08-05 22:21:53 +00:00

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2 Commits

Author	SHA1	Message	Date
enricobuehler	5f71aeb024	feat(flatpak): vendor the gamescope WSI layer so Deck HDR works on a plain install ... HDR on a Deck needed a manual second step nobody took: flatpak install --user flathub org.freedesktop.Platform.VulkanLayer.gamescope//25.08 documented only in a comment in this file. Build the layer ourselves instead, so a plain `flatpak install` is all it takes. The layer is genuinely required, not legacy. Measured on SteamOS 3.8.16 (gamescope 3.16.23.4): the gamescope-0 socket advertises gamescope_swapchain_factory_v2 but NOT wp_color_manager_v1, with HDR both off and on — so Mesa's Wayland WSI has no colour-management protocol to negotiate HDR10 through, and this layer is the only thing that can append the ST.2084 surface formats. Removing the extension gives zero [Gamescope WSI] lines and hdr10_format=None. Vendored rather than declared via add-extensions autodownload: the extension is 94 MB of whole-gamescope for one 4 MB .so, its layer JSON hardcodes a /usr library_path that an app-scoped extension mounted under /app would not satisfy, and it would make flathub a hard install-time dependency of an app we self-host on flatpak.unom.io. enable_gamescope=false skips subdir('src') and every compositor dependency, so only protocol/ and layer/ build. buildsystem is simple rather than meson because glm and stb ship no meson.build of their own - the wraps' patch_directory supplies it, and without that copy configure dies with "Subproject exists but has no meson.build file". meson generates the layer JSON from prefix+libdir, so it self-writes library_path=/app/lib/... into /app/share/vulkan/implicit_layer.d, which XDG_DATA_DIRS already covers. VK_ADD_IMPLICIT_LAYER_PATH is therefore dropped - keeping it would also risk double-loading two same-named layers for anyone who still has the flathub extension installed. Pinned to the same gamescope rev as packaging/gamescope/PKGBUILD so the client's layer and the host's punktfunk-gamescope come from one tree. Verified on a Deck OLED: builds offline (--wrap-mode=nodownload) in org.gnome.Sdk//50, and the resulting .so drives the Deck's system gamescope to "hdr formats exposed to client: true" with hdr10_format=Some(A2B10G10R10_UNORM_PACK32, HDR10_ST2084_EXT). Still user-side, and not fixable in packaging: gamescope's hdr_enabled convar (Steam's HDR display setting) must be on.	2026-08-06 00:15:16 +02:00
enricobuehler	e1adc5d6d7	fix(flatpak): export GAMESCOPE_WAYLAND_DISPLAY so the Deck actually gets HDR ... The gamescope WSI layer decides whether to engage from one signal: isRunningUnderGamescope() reads $GAMESCOPE_WAYLAND_DISPLAY and nothing else. flatpak does not forward host env into the sandbox, so it arrived unset and the layer's CreateInstance early-returned before creating a GamescopeInstance — no gamescope surface, so the HDR10/ST.2084 formats were never appended and the surface stayed SDR. The layer still loads and still logs its generic bits in that state, so it reads as working. It is not: the three settings already here (layer search path, ENABLE_GAMESCOPE_WSI, the socket bind) all sit downstream of this gate and buy nothing without it. Measured on a Deck OLED (Galileo, SteamOS 3.8.16), client --browse, reading "swapchain config": unset -> no [Gamescope WSI] Surface state block, None set, hdr_enabled=0 -> server hdr output enabled: false, None set, hdr_enabled=1 -> hdr formats exposed to client: true, Some(A2B10G10R10_UNORM_PACK32, HDR10_ST2084_EXT) Matches the field report of "HDR->SDR" in the stats overlay on a correct HDR host. DXVK_HDR was ruled out by measurement. The remaining gate (gamescope's hdr_enabled convar = Steam's HDR display setting) is a user-side step, not a packaging one.	2026-08-05 23:59:45 +02:00