Vulkan extensions used by Monado

	Client	XCB server (a)	Wayland server (a)	Xlib-xrandr server (b)	NVIDIA xrandr server (b)	Android server	Windows server
Instance extensions
VK_KHR_external_fence_capabilities (8)	yes?
VK_KHR_external_memory_capabilities (8)	yes?
VK_KHR_external_semaphore_capabilities (8)	yes?
VK_KHR_get_physical_device_properties2 (8)	yes
VK_KHR_surface		yes
VK_KHR_display				yes (2) (requires VK_KHR_surface)
Platform-specific instance extensions
VK_KHR_xcb_surface		yes (1, 4)
VK_KHR_wayland_surface			yes (1, 4)
VK_EXT_direct_mode_display				yes (1)	yes (2)
VK_EXT_acquire_xlib_display				yes (1) (in shared code)
VK_KHR_android_surface						yes (1, 4)
VK_KHR_win32_surface							yes (1, 4)
Device Extensions
VK_KHR_get_memory_requirements2 (8)	yes
VK_KHR_dedicated_allocation (8)	yes? (requires VK_KHR_get_memory_requirements2)
VK_KHR_external_fence (8) (+platform: 5)	yes (soon)
VK_KHR_external_memory (8) (+platform: 6)	yes
VK_KHR_external_semaphore (8) (+platform: 7)	yes (soon)
VK_KHR_swapchain		yes
[VK_KHR_timeline_semaphore][]	opt	opt	opt	opt	opt	opt	opt

VK_EXT_debug_utils is also used.

Notes

Kept out of the preceding table to limit its width.

• Server type:
  • a: Windowed
  • b: Direct mode
• Usage details/reason:
  • 1: Used directly
  • 2: Dependency of VK_EXT_direct_mode_display
  • 3: Dependency of VK_EXT_acquire_xlib_display
  • 4: Platform extension building on VK_KHR_surface
  • 5: Platform-specific extensions building on VK_KHR_external_fence:
    • Linux and Android: VK_KHR_external_fence_fd
    • Windows: VK_KHR_external_fence_win32
    • Note: These platform-specific extensions were not promoted to Core in Vulkan 1.1, only the platform-independent base extension.
  • 6: Platform-specific extensions building on VK_KHR_external_memory:
    • Linux: VK_KHR_external_memory_fd
    • Android: VK_ANDROID_external_memory_android_hardware_buffer (fd also usually available?)
    • Windows: VK_KHR_external_memory_win32
    • Note: These platform-specific extensions were not promoted to Core in Vulkan 1.1, only the platform-independent base extension.
  • 7: Platform-specific extensions building on VK_KHR_external_semaphore:
    • Linux and Android: VK_KHR_external_semaphore_fd
    • Windows: VK_KHR_external_semaphore_win32
    • Note: These platform-specific extensions were not promoted to Core in Vulkan 1.1, only the platform-independent base extension.
  • 8: Promoted to Vulkan 1.1 Core

Reasons

• Instance extensions:
  • VK_KHR_surface - for configuring output surface.
  • VK_KHR_get_physical_device_properties2 - for getting device UUID to share between client compositor and main/native compositor.
• Device extensions:
  • VK_KHR_swapchain - for displaying output on a display output.

Code locations

• Client
  • Instance extensions: xrt_gfx_vk_instance_extensions
  • Device extensions: xrt_gfx_vk_device_extensions
• Server
  • All these are in comp_compositor.c, with the extensions required by all servers defined in COMP_INSTANCE_EXTENSIONS_COMMON
  • XCB (Windowed) Server: instance_extensions_xcb
  • Wayland (Windowed) Server: instance_extensions_wayland
  • Xlib-xrandr direct mode server and NVIDIA direct mode server: instance_extensions_direct_mode
  • Android server: instance_extensions_android
  • Windows server: instance_extensions_windows