Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell2010 |
Name
VK_NV_acquire_winrt_display - device extension
VK_NV_acquire_winrt_display
- Name String
VK_NV_acquire_winrt_display
- Extension Type
- Device extension
- Registered Extension Number
- 346
- Revision
- 1
- Ratification Status
- Not ratified
- Extension and Version Dependencies
- VK_EXT_direct_mode_display
- Contact
Other Extension Metadata
- Last Modified Date
- 2020-09-29
- IP Status
- No known IP claims.
- Contributors
- Jeff Juliano, NVIDIA
Description
This extension allows an application to take exclusive control of a display on Windows 10 provided that the display is not already controlled by a compositor. Examples of compositors include the Windows desktop compositor, other applications using this Vulkan extension, and applications that “Acquire” a “DisplayTarget” using a “WinRT” command such as “winrt::Windows::Devices::Display::Core::DisplayManager.TryAcquireTarget()”.
When control is acquired the application has exclusive access to the display until control is released or the application terminates. An application’s attempt to acquire is denied if a different application has already acquired the display.
New Commands
New Enum Constants
Issues
1) What should the platform substring be for this extension:
RESOLVED: The platform substring is “Winrt”.
The substring “Winrt” matches the fact that the OS API exposing the acquire and release functionality is called “WinRT”.
The substring “Win32” is wrong because the related “WinRT” API is explicitly not a “Win32” API. “WinRT” is a competing API family to the “Win32” API family.
The substring “Windows” is suboptimal because there could be more than one relevant API on the Windows platform. There is preference to use the more-specific substring “Winrt”.
2) Should acquireWinrtDisplayNV
take a winRT DisplayTarget, or a
Vulkan display handle as input?
RESOLVED: A Vulkan display handle. This matches the design of
acquireXlibDisplayEXT
.
3) Should the acquire command be platform-independent named “vkAcquireDisplayNV”, or platform-specific named “vkAcquireWinrtDisplayNV”?
RESOLVED: Add a platform-specific command.
The inputs to the Acquire command are all Vulkan types. None are WinRT types. This opens the possibility of the winrt extension defining a platform-independent acquire command.
The X11 acquire command does need to accept a platform-specific
parameter. This could be handled by adding to a platform-independent
acquire command a params struct to which platform-dependent types can be
chained by pNext
pointer.
The prevailing opinion is that it would be odd to create a second platform-independent function that is used on the Windows 10 platform, but that is not used for the X11 platform. Since a Windows 10 platform-specific command is needed anyway for converting between vkDisplayKHR and platform-native handles, opinion was to create a platform-specific acquire function.
4) Should the getWinrtDisplayNV
parameter identifying a display be
named “deviceRelativeId” or “adapterRelativeId”?
RESOLVED: The WinRT name is “AdapterRelativeId”. The name “adapter”
is the Windows analog to a Vulkan “physical device”. Vulkan already has
precedent to use the name deviceLUID
for the concept that Windows APIs
call “AdapterLuid”. Keeping form with this precedent, the name
“deviceRelativeId” is chosen.
5) Does acquireWinrtDisplayNV
cause the Windows desktop compositor to
release a display?
RESOLVED: No. acquireWinrtDisplayNV
does not itself cause the
Windows desktop compositor to release a display. This action must be
performed outside of Vulkan.
Beginning with Windows 10 version 2004 it is possible to cause the Windows desktop compositor to release a display by using the “Advanced display settings” sub-page of the “Display settings” control panel. See https://docs.microsoft.com/en-us/windows-hardware/drivers/display/specialized-monitors
6) Where can one find additional information about custom compositors for Windows 10?
RESOLVED: Relevant references are as follows.
According to Microsoft’s documentation on "building a custom compositor", the ability to write a custom compositor is not a replacement for a fullscreen desktop window. The feature is for writing compositor apps that drive specialized hardware.
Only certain editions of Windows 10 support custom compositors, "documented here". The product type can be queried from Windows 10. See https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getproductinfo
Version History
Revision 1, 2020-09-29 (Jeff Juliano)
- Initial draft
See Also
acquireWinrtDisplayNV
, getWinrtDisplayNV
Document Notes
For more information, see the Vulkan Specification
This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.
Synopsis
- acquireWinrtDisplayNV :: forall io. MonadIO io => PhysicalDevice -> DisplayKHR -> io ()
- getWinrtDisplayNV :: forall io. MonadIO io => PhysicalDevice -> ("deviceRelativeId" ::: Word32) -> io DisplayKHR
- type NV_ACQUIRE_WINRT_DISPLAY_SPEC_VERSION = 1
- pattern NV_ACQUIRE_WINRT_DISPLAY_SPEC_VERSION :: forall a. Integral a => a
- type NV_ACQUIRE_WINRT_DISPLAY_EXTENSION_NAME = "VK_NV_acquire_winrt_display"
- pattern NV_ACQUIRE_WINRT_DISPLAY_EXTENSION_NAME :: forall a. (Eq a, IsString a) => a
- newtype DisplayKHR = DisplayKHR Word64
Documentation
acquireWinrtDisplayNV Source #
:: forall io. MonadIO io | |
=> PhysicalDevice |
|
-> DisplayKHR |
|
-> io () |
vkAcquireWinrtDisplayNV - Acquire access to a VkDisplayKHR
Description
All permissions necessary to control the display are granted to the
Vulkan instance associated with physicalDevice
until the display is
released or the application is terminated. Permission to access the
display may be revoked by events that cause Windows 10 itself to lose
access to display
. If this has happened, operations which require
access to the display must fail with an appropriate error code. If
permission to access display
has already been acquired by another
entity, the call must return the error code
ERROR_INITIALIZATION_FAILED
.
Note
The Vulkan instance acquires control of a “winrt::Windows::Devices::Display::Core::DisplayTarget” by performing an operation equivalent to “winrt::Windows::Devices::Display::Core::DisplayManager.TryAcquireTarget()” on the “DisplayTarget”.
Note
One example of when Windows 10 loses access to a display is when the display is hot-unplugged.
Note
One example of when a display has already been acquired by another
entity is when the Windows desktop compositor (DWM) is in control of the
display. Beginning with Windows 10 version 2004 it is possible to cause
DWM to release a display by using the “Advanced display settings”
sub-page of the “Display settings” control panel.
acquireWinrtDisplayNV
does not itself cause DWM to release a display;
this action must be performed outside of Vulkan.
Return Codes
See Also
:: forall io. MonadIO io | |
=> PhysicalDevice |
|
-> ("deviceRelativeId" ::: Word32) |
|
-> io DisplayKHR |
vkGetWinrtDisplayNV - Query the VkDisplayKHR corresponding to a WinRT DisplayTarget
Description
If there is no DisplayKHR
corresponding to
deviceRelativeId
on physicalDevice
,
NULL_HANDLE
must be returned in
pDisplay
.
Return Codes
See Also
type NV_ACQUIRE_WINRT_DISPLAY_SPEC_VERSION = 1 Source #
pattern NV_ACQUIRE_WINRT_DISPLAY_SPEC_VERSION :: forall a. Integral a => a Source #
type NV_ACQUIRE_WINRT_DISPLAY_EXTENSION_NAME = "VK_NV_acquire_winrt_display" Source #
pattern NV_ACQUIRE_WINRT_DISPLAY_EXTENSION_NAME :: forall a. (Eq a, IsString a) => a Source #
newtype DisplayKHR Source #
VkDisplayKHR - Opaque handle to a display object
See Also
VK_KHR_display,
DisplayPlanePropertiesKHR
,
DisplayPropertiesKHR
,
acquireDrmDisplayEXT
,
acquireWinrtDisplayNV
,
acquireXlibDisplayEXT
,
createDisplayModeKHR
,
displayPowerControlEXT
,
getDisplayModeProperties2KHR
,
getDisplayModePropertiesKHR
,
getDisplayPlaneSupportedDisplaysKHR
,
getDrmDisplayEXT
,
getRandROutputDisplayEXT
,
getWinrtDisplayNV
,
registerDisplayEventEXT
,
releaseDisplayEXT