Bumped spec version to 5 with many changes

This addresses a lot of the feedback from the past couple of months.

- Changed `VkPresentTimesInfoEXT` and `VkPresentTimeInfoEXT` to
`VkPresentTimingsInfoEXT` and `VkPresentTimingInfoEXT` because those structs
contain more than just time values now.

- Remove `presentStageQueries` and `presentStageTarget` from
VkSwapchainPresentTimingCreateInfoEXT. These are specified per-present now, to
accomodate for dynamic surface capabilities.

- Remove vkSetSwapchainTimingEXT function and VkSwapchainTimingInfoEXT
structure. The state specified there is now sent per-present.

- Add a synchronous wait behavior to vkGetPastPresentationTimingEXT with a
`timeout` parameter, and the ability to explicitly reference present IDs as an
input.  vkGetPastPresentationTimingEXT also does not require external
synchronization anymore.

- Remove `timingPropertiesChanged` from `VkPastPresentationTimingEXT` struct
and make it an out parameter of vkGetPastPresentationTimingEXT. This means
applications don't need to wait for timing results to be available to know that
timing properties have changed.  This however creates a new problem where if
multiple results are returned, applications cannot distinguish the timing
properties of individual presents.

- Remove `timeDomainChanged` from `VkPastPresentationTimingEXT` struct and
replace it with the actual time domain enum it was changed to. The PE can
operate some fallback and communicate this to the app for each result. This
also creates a new problem if both the old and new time domains are the same
opaque one, e.g. different SWAPCHAIN_LOCAL domains. I have plans to address
this and the timing properties problem, but would like to discuss it in future
meetings first.

- Fix relative present timing language to correctly specify that the duration
is relative to the previous image, and not the next present.

And many other minor updates

appendices/VK_EXT_present_timing.adoc

@@ -7,7 +7,7 @@ include::{generated}/meta/{refprefix}VK_EXT_present_timing.adoc[]
 === Other Extension Metadata
 
 *Last Modified Date*::
-    2023-03-07
+    2024-02-10
 *IP Status*::
     No known IP claims.
 *Contributors*::
@@ -247,3 +247,8 @@ Split it out into its own extension and define the interaction here.
 
   * Revision 4, 2023-05-03 (Lionel Duc)
   ** Change target and feedback times to be associated with a well-defined present stage.
+
+  * Revision 5, 2024-02-10 (Lionel Duc)
+  ** Move swapchain state into per-present struct, removing the need for vkSetSwapchainTimingEXT
+  ** Add synchronous behavior to vkGetPastPresentationTimingEXT
+  ** Add stage-local time domain

appendices/glossary.adoc

@@ -836,7 +836,8 @@ Image Present Duration::
 Image Present Rate::
     The number of newly-presented images the application intends to present
     each second (a.k.a. frame rate).
-    This value should: be a multiple of the refresh rate.
+    On fixed refresh rate displays, this value should: be a multiple of
+    the refresh rate.
 endif::VK_EXT_present_timing,VK_GOOGLE_display_timing[]
 
 Image Subresource::

chapters/VK_EXT_present_timing/PresentTimeInfo.adoc

@@ -2,43 +2,35 @@
 //
 // SPDX-License-Identifier: CC-BY-4.0
 
-[open,refpage='VkPresentTimesInfoEXT',desc='The earliest time each image should be presented',type='structs']
+[open,refpage='VkPresentTimingsInfoEXT',desc='Array of VkPresentTimingInfoEXT to chain with VkPresentInfoKHR',type='structs']
 --
 
 When the <<features-presentAtAbsoluteTime, pname:presentAtAbsoluteTime>> or
 <<features-presentAtRelativeTime, pname:presentAtRelativeTime>> feature is
-enabled, additional fields can: be specified that allow an application to
-specify the earliest time that an image should: be displayed.
-This allows an application to avoid stutter that is caused by an image being
-displayed earlier than planned.
-Such stuttering might occur with both fixed and variable-refresh-rate
-displays, because stuttering occurs when the geometry is not correctly
-positioned for when the image is displayed.
-An application can: instruct the presentation engine that an image must:
-not be displayed earlier than a specified time by including the
-sname:VkPresentTimesInfoEXT structure in the pname:pNext chain of the
-sname:VkPresentInfoKHR structure.
-
-The sname:VkPresentTimesInfoEXT structure is defined as:
-
-include::{generated}/api/structs/VkPresentTimesInfoEXT.adoc[]
-
-  * pname:sType is the type of this structure.
+enabled, an application can: instruct the presentation engine that an image
+must: not be displayed earlier than a specified time, or for a minimum
+duration, by including the sname:VkPresentTimingsInfoEXT structure in the
+pname:pNext chain of the slink:VkPresentInfoKHR structure.
+
+The sname:VkPresentTimingsInfoEXT structure is defined as:
+
+include::{generated}/api/structs/VkPresentTimingsInfoEXT.adoc[]
+
+  * pname:sType is a elink:VkStructureType value identifying this structure.
   * pname:pNext is `NULL` or a pointer to a structure extending this
     structure.
   * pname:swapchainCount is the number of swapchains being presented to by
     this command.
-  * pname:pTimes is `NULL` or a pointer to an array of
-    sname:VkPresentTimeEXT elements with pname:swapchainCount entries.
-    If not `NULL`, each element of pname:pTimes contains the earliest present
-    time or the minimum present duration for the image corresponding to the
-    entry in the sname:VkPresentInfoKHR::pname:pImageIndices array.
+  * pname:pTimingInfos is `NULL` or a pointer to an array of
+    sname:VkPresentTimingInfoEXT elements with pname:swapchainCount entries.
+    If not `NULL`, each element of pname:pTimingInfos contains timing
+    information for the presentation of the image corresponding to the entry
+    in the sname:VkPresentInfoKHR::pname:pImageIndices array.
 
-The semantics of a specified target present time or duration only apply to
-the following present modes:
+The semantics of target presentation time or duration vary depending on the presentation mode:
 
   * ename:VK_PRESENT_MODE_FIFO_KHR.
-    Tearing cannot be observed.
+    Tearing cannot: be observed.
     The first queued image is dequeued and presented if
     both: 1) its associated wait semaphore(s) have signaled, and 2)
     its target present time is less-than or equal-to the current time.
@@ -52,25 +44,62 @@ the following present modes:
     displayed at the start of the vertical blanking period, or may: be
     treated the same as for ename:VK_PRESENT_MODE_IMMEDIATE_KHR.
 
+Other presentation modes do not support a target presentation time or duration.
+
 .Valid Usage
 ****
   * pname:swapchainCount must: be the same value as
     sname:VkPresentInfoKHR::pname:swapchainCount, where
     sname:VkPresentInfoKHR is in the pname:pNext chain of this
-    sname:VkPresentTimesInfoEXT structure.
+    sname:VkPresentTimingsInfoEXT structure.
   * For each member of sname:VkPresentInfoKHR::pname:pSwapchains, if the
-    associated sname:VkPresentTimeEXT is non-zero, the present mode must:
-    be ename:VK_PRESENT_MODE_FIFO_KHR or
+    associated sname:VkPresentTimeEXT is non-zero, the current present mode
+    must: be ename:VK_PRESENT_MODE_FIFO_KHR or
     ename:VK_PRESENT_MODE_FIFO_RELAXED_KHR.
-  * For each member of sname:VkPresentInfoKHR::pname:pSwapchains, if the
-    associated sname:VkPresentTimeEXT is non-zero, the swapchain must: have
-    been created with a non-zero
-    sname:VkSwapchainPresentTimingCreateInfoEXT::pname:presentStageTarget
 ****
 
-include::{generated}/validity/structs/VkPresentTimesInfoEXT.adoc[]
+include::{generated}/validity/structs/VkPresentTimingsInfoEXT.adoc[]
 --
 
+
+[open,refpage='VkPresentTimingInfoEXT',desc='Specifies per-present per-swapchain timing information',type='structs']
+--
+The sname:VkPresentTimingInfoEXT structure is defined as:
+
+include::{generated}/api/structs/VkPresentTimingInfoEXT.adoc[]
+
+  * pname:sType is a elink:VkStructureType value identifying this structure.
+  * pname:pNext is `NULL` or a pointer to a structure extending this
+    structure.
+  * pname:time is a sname:VkPresentTimeEXT specifying the target present
+    time or duration of the presentation request.
+  * pname:timeDomain is the time domain used to specify the absolute target
+    present time and the timing results in a subsequent
+    flink:vkGetPastPresentationTimingEXT call for the current presentation
+    request.
+  * pname:presentStageQueries is a valid tlink:VkPresentStageFlagsEXT value
+    indicating which present stages the presentation engine should collect
+    timing information for.
+  * pname:targetPresentStage is zero or a tlink:VkPresentStageFlagsEXT value
+    specifying which present stage pname:time is targeting.
+  * pname:presentAtNearestRefreshCycle is a flag indicating that the
+    application would like to complete pname:targetPresentStage at the start
+    of the refresh cycle that is closest to pname:time. If
+    pname:presentAtNearestRefreshCycle is ename:VK_TRUE, the presentation
+    engine may: complete the target present stage earlier than specified in
+    pname:time.
+
+.Valid Usage
+****
+  * If pname:presentStageTarget is not zero, it must: specify one and only
+    one stage.
+  * pname:presentStageTarget must: not be ename:VK_PRESENT_STAGE_IMAGE_HANDOFF_BIT_EXT
+****
+
+include::{generated}/validity/structs/VkPresentTimingInfoEXT.adoc[]
+--
+
+
 [open,refpage='VkPresentTimeEXT',desc='Specifying when an image should be presented',type='structs']
 --
 
@@ -79,27 +108,29 @@ The sname:VkPresentTimeEXT union is defined as:
 include::{generated}/api/structs/VkPresentTimeEXT.adoc[]
 
   * pname:targetPresentTime, if non-zero, specifies the earliest time the
-    application wants the image to complete the swapchain's target present
-    stage. A value of zero specifies that the presentation engine may:
-    display the image at any time allowed by the current present mode.
-  * pname:minPresentDuration, if non-zero, specifies the minimum duration in
-    nanoseconds before which the next image presentation request can: reach
-    the target present stage. A value of zero specifies that the
-    presentation engine may: display the image for any duration allowed by
-    the current present mode.
+    application wants the presentation engine to complete the swapchain's
+    target present stage. A value of zero specifies that the presentation
+    engine may: display the image at any time allowed by the current present
+    mode.
+  * pname:afterPresentDuration, if non-zero, specifies the minimum duration
+    in nanoseconds before which the next image presentation request can:
+    reach the target present stage, relative to the previous presentation
+    reaching that same stage. A value of zero specifies that the
+    presentation engine may: display the previous image for any duration
+    allowed by the current present mode.
 
 The contents of the sname:VkPresentTimeEXT union is interpreted depending on
 the associated sname:VkPresentInfoKHR::pname:pSwapchains member creation
 values. If
 sname:VkSwapchainPresentTimingCreateInfoEXT::pname:presentAtRelativeTime was
 ename:VK_FALSE when creating the pname:swapchain, pname:targetPresentTime is
-used. Otherwise, pname:minPresentDuration is used.
+used. Otherwise, pname:afterPresentDuration is used.
 
 pname:targetPresentTime is a time in nanoseconds, according to the
-time-domain being used. The presentation engine must: not complete the
-target present stage, specified in the associated swapchain
-slink:VkSwapchainPresentTimingCreateInfoEXT::pname:presentStageTarget, at an
-earlier time.
+time-domain specified in the associated
+slink:VkPresentTimingInfoEXT::pname:timeDomain. The presentation engine
+must: not complete the target present stage specified in
+slink:VkPresentTimingInfoEXT::pname:targetPresentStage at an earlier time.
 
 [NOTE]
 .Note
@@ -115,18 +146,6 @@ subtract a small delta from pname:targetPresentTime as a margin for error.
 include::{generated}/validity/structs/VkPresentTimeEXT.adoc[]
 --
 
-[open,refpage='VkPresentStageTimeEXT',desc='Associate a present stage with a timestamp',type='structs']
---
-The sname:VkPresentStageTimeEXT structure is defined as:
-
-include::{generated}/api/structs/VkPresentStageTimeEXT.adoc[]
-
-  * pname:stage is a tlink:VkPresentStageFlagsEXT value specifying a present stage.
-  * pname:time is a time in nanoseconds associated with the pname:stage.
-
-include::{generated}/validity/structs/VkPresentStageTimeEXT.adoc[]
---
-
 [open,refpage='VkPresentStageFlagBitsEXT',desc='Bitmask specifying stages of the image presentation process',type='enums']
 --