baketnk--frame-yap/docs/evidence/vulkan-overlay-2026-09-24.md

Persistent Vulkan overlay deployment — 2026-09-24

Source commit: 4c043c99. Installed native ARM64 version: 2026-09-24T181314Z-g4c043c99.

The user requested replacing raw uploads with a GPU texture and supplied the current Frame SSH target and key for native build/install verification. These are dated observations, not future device availability or permission to launch hardware checks.

Implementation

The overlay now uses SetOverlayTexture with a persistent Vulkan RGBA8 image. The CPU panel rasterizer still produces the pixels. One staging allocation, image and command buffer are reused; redraws do not recreate them. SteamVR selects the physical device and required instance/device extensions. Transfers share one FrameYap-owned graphics queue with SteamVR, and GPU resources survive until VR_Shutdown completes. No desktop surface, swapchain or raw-upload fallback was introduced. See rendering details.

Verification

• Default local offline build: 13/13 CTest checks passed.
• Local native build: all 16 checks passed; the fake Wayland protocol check required permission to bind its local test socket outside the sandbox.
• Native ARM64 Release build on Frame from a checksum-verified Git archive: 16/16 hardware-free checks passed, including the Vulkan fake-driver test.
• Explicit offscreen Vulkan check on the workstation's RTX 4090, with VK_LAYER_KHRONOS_validation enabled: eight exact 1000×680 RGBA readbacks, one stable image, no validation messages.
• The same explicit offscreen check on Frame's Turnip Adreno (TM) 750: eight exact 1000×680 RGBA readbacks and one stable image. This exercised the actual image upload/layout/readback path, without OpenVR initialization.
• Staged and installed native dependency resolution succeeded. Vulkan resolves to the system loader; SDL/OpenVR resolve inside FrameYap's own lib/.
• The native archive was checksum-verified and installed. current selects the version above; previous retains 2026-09-24T174700Z-gc59c8b1. Installed --version matched and its executable hash matched the staged binary. No app, SSH or user-session process was terminated.

Native archive SHA-256: d6f0173b25a879c02f0ee67063c881a23dff874a71674826ddd7666d0980759d. Installed executable SHA-256: 761ea0e4d2dc235c5f056d8d944cb68392713c246aaec008d0b6c235954ef645.

Acceptance boundary

The updated headset installation is verified, but this session did not launch an OpenVR visual/controls probe or collect a wearer report. GPU readback does not establish SteamVR texture acceptance, orientation, click behavior or a flicker fix. No microphone, inference or text/Enter delivery was exercised. The next human headset check should compare both static action clicks and content-changing tabs using the installed Vulkan build's --check-controls.