Launcher/build-dawn-linux.sh builds the pinned Dawn with Aurora's Vulkan hook
and density map patches into a package local-build.sh takes through the new
--dawn-package option, together with --openxr, --headset steam_frame and
--cpu. docs/steam-frame.md now leads with the native SteamOS build (building
in a podman container on the Frame, running it, the log lines to expect);
OPENXR.md's backend table records the Linux Vulkan backend and why the Lepton
flavour cannot present.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
Lepton's Vulkan driver has no external memory or sync fd extensions,
so the Steam Frame gets a native SteamOS build instead. Its backend is
the PC's: OpenXR creates Dawn's own Vulkan instance and device, and the
eyes are copied into the swapchain on Dawn's queue, with nothing shared
between devices.
- openxr_vulkan_win32 and Aurora's vulkan_win32_interop now compile on
desktop Linux. Dawn links statically there, so the bridge calls the
patched package's hooks directly, and exists only when the package's
aurora-dawn.json declares the Vulkan hook ABI (AuroraDawnProvider
turns AuroraVulkanAbi into AURORA_DAWN_VULKAN_HOOKS); a stock Dawn
keeps the stubs and VR falls back to the desktop.
- openxr_integration.cpp gains a Linux branch: XR_KHR_vulkan_enable2,
the timespec clock, refresh rate, performance level, the Frame
controllers and eye gaze; fragment density maps are requested on
Linux as on the Quest (fdm.cpp and gpu.cpp, AURORA_FDM=0/1 overrides).
- Controller motion uses XR_KHR_convert_timespec_time on any Linux.
- CMake: Vulkan headers are fetched for Linux OpenXR builds, the
headset option is MKW_HEADSET on Android and Linux, and Linux aarch64
builds take MKW_LINUX_CPU (cortex-x4 for the Steam Frame, else native).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
The Capability Viewer inside Lepton shows no AHardwareBuffer, external
memory fd, semaphore fd or fence fd extension, so the Quest backend's
two-device eye handoff cannot present there; the eyes need to be copied
on Dawn's own device bound to the session, as on Windows Vulkan.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
Read from Walkabout Mini Golf's Unity log on the Frame: the Frame
controller profile, display refresh rate, eye gaze and performance
settings are all there; XR_KHR_convert_timespec_time is not, so VR
frame interpolation is unavailable on the Frame.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
Lepton ships /vendor/etc/openxr/1/active_runtime.json and Valve's
implicit fdm_injection layer instead of a runtime broker; the statically
linked Khronos loader falls back to that file, so the app needs no
change.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
The Frame's kernel reports sve, sve2 and the SVE2 extensions in its
HWCAP, on SteamOS and inside Lepton alike, unlike phones with the same
Snapdragon 8 Gen 3. The steamFrame flavour now builds with
-mcpu=cortex-x4 instead of cortex-x4+nosve.
docs/steam-frame.md records what the headset reported: 4 KB pages,
Android 11 (API 30) in a Waydroid-based Lepton, Mesa's Turnip as its
Vulkan driver, and SteamVR's native linuxarm64 OpenXR runtime on the
host, with the questions still open.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
The adb commands named the device through a PowerShell variable, which
fish and bash do not read; each line now names it, and two grep lines
pull the driver and the relevant extensions out of the vkjson dump.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3
docs/steam-frame.md covers the steamFrame flavour: the CPU target and
why it excludes SVE, the Lepton entry activity and manifest, the Frame
controller map, the refresh rate and eye-tracked foveation, building and
installing, the device checklist (what to collect from the headset, the
log lines a first session should show, the open questions), and what a
native SteamOS build would need. OPENXR.md documents refresh_rate and
eye_tracked_foveation and the Frame controller profile; the Quest doc,
the Android README and the README point to it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019HBRGKTE1GnN2ah8gcZKr3