VkPresentModeKHR - Presentation mode supported for a surface
Description
PRESENT_MODE_IMMEDIATE_KHR specifies that the presentation engine
does not wait for a vertical blanking period to update the current
image, meaning this mode may result in visible tearing. No
internal queuing of presentation requests is needed, as the requests
are applied immediately.
PRESENT_MODE_MAILBOX_KHR specifies that the presentation engine
waits for the next vertical blanking period to update the current
image. Tearing cannot be observed. An internal single-entry queue
is used to hold pending presentation requests. If the queue is full
when a new presentation request is received, the new request
replaces the existing entry, and any images associated with the
prior entry become available for reuse by the application. One
request is removed from the queue and processed during each vertical
blanking period in which the queue is non-empty.
PRESENT_MODE_FIFO_KHR specifies that the presentation engine waits
for the next vertical blanking period to update the current image.
Tearing cannot be observed. An internal queue is used to hold
pending presentation requests. New requests are appended to the end
of the queue, and one request is removed from the beginning of the
queue and processed during each vertical blanking period in which
the queue is non-empty. This is the only value of presentMode that
is required to be supported.
PRESENT_MODE_FIFO_RELAXED_KHR specifies that the presentation
engine generally waits for the next vertical blanking period to
update the current image. If a vertical blanking period has already
passed since the last update of the current image then the
presentation engine does not wait for another vertical blanking
period for the update, meaning this mode may result in visible
tearing in this case. This mode is useful for reducing visual
stutter with an application that will mostly present a new image
before the next vertical blanking period, but may occasionally be
late, and present a new image just after the next vertical blanking
period. An internal queue is used to hold pending presentation
requests. New requests are appended to the end of the queue, and one
request is removed from the beginning of the queue and processed
during or after each vertical blanking period in which the queue is
non-empty.
PRESENT_MODE_FIFO_LATEST_READY_KHR specifies that the presentation
engine waits for the next vertical blanking period to update the
current image. Tearing cannot be observed. An internal queue is
used to hold pending presentation requests. New requests are
appended to the end of the queue. At each vertical blanking period,
the presentation engine dequeues all successive requests that are
ready to be presented from the beginning of the queue. If using the
VK_GOOGLE_display_timing extension or the
presentAtAbsoluteTime
feature to provide a target present time, the presentation engine
checks the specified time for each image. If the target present time
is less-than or equal-to the current time, the presentation engine
dequeues the image and checks the next one. The image of the last
dequeued request is presented. The other dequeued requests are
dropped.
PRESENT_MODE_SHARED_DEMAND_REFRESH_KHR specifies that the
presentation engine and application have concurrent access to a
single image, which is referred to as a shared presentable image.
The presentation engine is only required to update the current image
after a new presentation request is received. Therefore the
application must make a presentation request whenever an update is
required. However, the presentation engine may update the current
image at any point, meaning this mode may result in visible
tearing.
PRESENT_MODE_SHARED_CONTINUOUS_REFRESH_KHR specifies that the
presentation engine and application have concurrent access to a
single image, which is referred to as a shared presentable image.
The presentation engine periodically updates the current image on
its regular refresh cycle. The application is only required to make
one initial presentation request, after which the presentation
engine must update the current image without any need for further
presentation requests. The application can indicate the image
contents have been updated by making a presentation request, but
this does not guarantee the timing of when it will be updated. This
mode may result in visible tearing if rendering to the image is
not timed correctly.
The supported
ImageUsageFlagBits of the
presentable images of a swapchain created for a surface may differ
depending on the presentation mode, and can be determined as per the
table below:
Presentable Image Usage Queries
For reference, the mode indicated by PRESENT_MODE_FIFO_KHR is
equivalent to the behavior of {wgl|glX|egl}SwapBuffers with a swap
interval of 1, while the mode indicated by
PRESENT_MODE_FIFO_RELAXED_KHR is equivalent to the behavior of
{wgl|glX}SwapBuffers with a swap interval of -1 (from the
{WGL|GLX}_EXT_swap_control_tear extensions).
See Also
VK_KHR_surface,
LatencySurfaceCapabilitiesNV,
SurfacePresentModeCompatibilityKHR,
SurfacePresentModeKHR,
SwapchainCreateInfoKHR,
SwapchainPresentModeInfoKHR,
SwapchainPresentModesCreateInfoKHR,
getPhysicalDeviceSurfacePresentModes2EXT,
getPhysicalDeviceSurfacePresentModesKHR