* Bump API patch number and header version number to 58 for this update.
Github Issues:
* Update the <<interfaces-resources-descset,Descriptor Set Interface>>
section to allow multiple variables with the same descriptor set/binding
decorations, and require that all variables that are statically used
must be consistent with the pipeline layout. Allow
ename:VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER to be used with texture
and sampler variables (public issues 522, 524).
Internal Issues:
* Replace networkx package used for extension dependency generation with a
homegrown network dependency traverser (internal issue 713).
* Specify in the <<interfaces-fragmentoutput, Fragment Output Interface>>
section that if a fragment shader writes integers that cannot be
represented in the format of the colour attachment, then the result is
undefined (internal issue 893).
* Separate malformed valid usage statement for
slink:VkPipelineRasterizationStateCreateInfo into two (internal issue
918).
* Fix cases where the term 'pNext chain' is incorrectly used in reference
to functions, rather than their parameters. Replace 'pNext list' with
'pNext chain'. Fixed typo in the example code of
+VK_KHR_dedicated_allocation+ (internal issue 944).
* Fix typo in elink:VkExternalSemaphoreHandleTypeFlagBitsKHR enum
descriptions, replacing
etext:VK_EXTERNAL_SEMAPHORE_HANDLE_TYPE_FENCE_FD_BIT_KHR with
ename:VK_EXTERNAL_SEMAPHORE_HANDLE_TYPE_SYNC_FD_BIT_KHR, and make the
description more consistent with
VK_EXTERNAL_FENCE_HANDLE_TYPE_SYNC_FD_BIT_KHR (internal issue 950).
Other Issues:
* Clarify how pipeline stage masks affect
<<synchronization-pipeline-stages-masks, access and synchronization
scopes>>.
* Clarify that dedicated allocations do not allow aliasing in the
flink:vkBindBufferMemory and flink:vkBindImageMemory valid usage
statements.
* Correct specification of pname:dynamicCount for push_constant token in
slink:VkIndirectCommandsLayoutNVX.
New Extensions:
* `VK_EXT_shader_viewport_index_layer`
* Bump API patch number and header version number to 57 for this update.
Github Issues:
* Fix error in description of ename:VK_FORMAT_ETC2_R8G8B8A8_SRGB_BLOCK
block size (public issue 342).
* Update documentation of ename:VK_PIPELINE_CREATE_ALLOW_DERIVATIVES_BIT
to explicitly mention both graphics and compute pipelines (public issue
525).
Internal Issues:
* Document that
slink:VkPhysicalDeviceLimits::pname:framebufferColorSampleCounts does
not cover integer formats (internal issue 550).
* Add a note under slink:VkImageViewCreateInfo describing how values meant
for one format can be sanitized when used via another format (internal
issue 927).
* Add valid usage statements to ftext:vkCmd* documenting that image
subresources used as attachments must not be accessed as non-attachments
in a render pass (internal issue 929).
* Remove obsolete 'validextensionstructs' attribute from +vk.xml+, the XML
schema, and the schema documentation (internal issue 946).
New Extensions:
* `VK_AMD_mixed_attachment_samples`
* `VK_EXT_post_depth_coverage`
* `VK_KHR_relaxed_block_layout`
* `VK_NV_depth_range_unrestricted`
* Bump API patch number and header version number to 56 for this update.
Github Issues:
* Add valid usage statements for commands introduced by
`VK_EXT_debug_report` and `VK_EXT_debug_marker` extensions, regarding
the valid pname:object and pname:objectType values (public issue 495).
* Modify `GL_KHR_vulkan_glsl` specification to document that uniform and
buffer block arrays each take only a single binding (public issue 514).
* Add `KHX` author tag to +vk.xml+ (public issue 526).
Internal Issues:
* Document use of code: macro for non-Vulkan APIs in the style guide
(internal issue 863).
* Document that reference page open block delimiters must not contain
asciidoc section markup in the style guide (internal issue 898).
* Fix <<spirvenv,SPIR-V appendix>> to say
code:VariablePointersStorageBuffer instead of
code:VariablePointersUniformBufferBlock (internal issue 928).
Other Commits:
* Add missing extension structures to dependency attributes in +vk.xml+.
New Extenions:
* `VK_EXT_depth_range_unrestricted`
* Bump API patch number and header version number to 55 for this update.
Github Issues:
* Removed unintended optional parameter in +vk.xml+ from the
pname:pWaitSemaphores member of slink:VkPresentInfoKHR, which resulted
in the generation of an incorrect implicit valid usage clause allowing
pname:pWaitSemaphores to be NULL even when pname:waitSemaphoreCount is
non-zero (public issue 491).
* Add missing attribute to +vk.xml+ documenting that
slink:VkSwapchainCounterCreateInfoEXT extends
slink:VkSwapchainCreateInfo (public issue 510).
* Add const qualifier for some `VK_EXT_debug_market` extension command
parameters that were missing it (public issue 513).
* Fix definition of q and level~base~ in
<<textures-image-level-selection,Image Level(s) Selection>> (public
issue 515).
* Clarify lifetime requirement for slink:VkRenderPass objects used in
object creation (public issue 516).
* Fix link to floating/normalized fixed-point conversion from
<<interfaces-fragmentoutput,Fragment Output Interface>> (public issue
521).
Internal Issues:
* Update the style guide to include the general structure of a Vulkan
command name, the specific rule for using "`Get`" vs. "`Enumerate`" in
names, and a table of verbs commonly used in command names (spinoff of
internal issue 753).
* Clarified the behavior of automatic layout transitions in case of
attachment views that are 2D or 2D array views of 3D images. In
addition, restructured the valid usage clauses corresponding to the
members of the slink:VkImageSubresourceRange structure and added missing
valid usage clauses for its pname:baseMipLevel and pname:baseArrayLayer
members (internal issues 803, 849).
* Modify `GL_KHR_vulkan_glsl` specification to allow explicit std430 on a
push_constant declaration (internal issue 919).
Other Commits:
* Modify <<synchronization-framebuffer-regions, Framebuffer Region
Dependencies>> to use synchronization scope terminology.
* Add ename:VK_COLOR_SPACE_EXTENDED_SRGB_NONLINEAR_EXT to the
`VK_EXT_swapchain_colorspace` extension.
* Replace XML comments with `comment` attributes and/or tags, to enable
tools which transform the XML without loss of information.
* Replace `validextensionstructs` with `structextends`, which is tagged in
the child structure instead of the parent. This makes it slightly
simpler to add new structs to the XML, causes fewer merge conflicts, and
the information is kept localized to the extension structures where it
belongs. The old `validextensionstructs` attributes will be retained
until we're certain this doesn't cause problems with known consumers of
+vk.xml+.
* Bump API patch number and header version number to 54 for this update.
Github Issues:
Internal Issues:
* Fix tessellation domain to have an upper-left origin in the
<<img-tessellation-topology-ul, tessellation toplogy image>> and related
language. CTS and all implementations were already doing this, it was
just a documentation bug that it was flipped to lower-left (internal
issue 603).
* Add a section to the style guide describing how VUID tags are changed
and removed when the corresponding Valid Usage statements are modified
(internal issue 829).
* Add explicit Valid Usage statement to
slink:VkPipelineDynamicStateCreateInfo to require that members of
pname:pDynamicStates must be unique (internal issue 851).
New Extensions:
* `VK_KHR_16bit_storage`
* `VK_KHR_dedicated_allocation`
* `VK_KHR_external_fence`
* `VK_KHR_external_fence_capabilities`
* `VK_KHR_external_fence_fd`
* `VK_KHR_external_fence_win32`
* `VK_KHR_get_memory_requirements2`
* `VK_KHR_storage_buffer_storage_class`
* `VK_KHR_variable_pointers`
Extensions Promoted From KHX To KHR Status:
* `VK_KHR_external_memory`
* `VK_KHR_external_memory_capabilities`
* `VK_KHR_external_memory_fd`
* `VK_KHR_external_memory_win32`
* `VK_KHR_external_semaphore`
* `VK_KHR_external_semaphore_capabilities`
* `VK_KHR_external_semaphore_fd`
* `VK_KHR_external_semaphore_win32`
* `VK_KHR_win32_keyed_mutex`
* Bump API patch number and header version number to 53 for this update.
Github Issues:
Internal Issues:
* Clarify mappings of coordinates for mutable, compatible image views in
slink:VkImageViewCreateInfo (internal issue 815).
* Make ename:VK_BIND_SFR_BIT require a logical device with multiple
physical devices, so that standard sparse image block dimensions are
only required on systems that support multi-GPU (internal issue 835).
* Convert all files from use of // refBegin .. // refEnd comments to
delimit ref pages, to use of open blocks, and update style guide
accordingly (internal issue 839).
* Add valid usage for slink:VkWriteDescriptorSet when performing updates
to a ename:VK_STORAGE_IMAGE descriptor with layout
ename:VK_IMAGE_LAYOUT_GENERAL.
* Add a hack to the validity generator script to support an odd
interaction between flink:vkCmdFillBuffer and an extension (internal
issue 853).
* Remove redundant text describing slink:VkBufferCreateInfo::pname:usage,
which was already covered by implicit valid usage (internal issue 854).
* Update implicit validity generator script to properly handle the
pname:sType and pname:pNext members of "returnedonly" structures
(internal issue 874).
* Note that slink:VkApplicationInfo::pname:pApplicationName &
slink:VkApplicationInfo::pname:pEngineName are optional, and add missing
implicit valid usage statements for flink:vkDestroyInstance.
* Added missing valid usage for flink:vkCmdWriteTimestamp to require a
timestamp query pool.
* Simplify and/or split "`non-atomic`" valid usage statements.
New Extensions:
* `VK_AMD_gpu_shader_int16`
* `VK_EXT_blend_operation_advanced`
* `VK_EXT_sampler_filter_minmax`
* `VK_NV_framebuffer_mixed_samples`
-----------------------------------------------------
Note: the 1.0.52 spec wasn't published on github, so the 1.0.53 release
combines both change sets.
-----------------------------------------------------
Change log for June 13, 2017 Vulkan 1.0.52 spec update:
* Bump API patch number and header version number to 52 for this update.
Github Issues:
Internal Issues:
* Clarify behavior when non-coherent memory has
<<memory-device-unmap-does-not-flush, not been flushed before being
unmapped>> (internal issue 819).
* Fix description of code:WorkgroupSize builtin to note it decorates an
object, not a variable (internal issue 836).
* Fix asciidoc attributes so that trailing '{plus}' symbols in [eq] style
equations are rendered properly (internal issue 845).
* Add language to the "`Extension Handles, Objects, Enums, and Typedefs`"
section of the Procedures and Conventions document stating that any new
handle type requires a corresponding entry in the elink:VkObjectType
enumerated type (internal issue 856).
* Update style guide to use slink macro for Vulkan handle type names, and
define narrow conditions under which to use the *name and *text macros
instead of *link (internal issue 886).
* Add a dependency of the <<VK_KHX_device_group,VK_KHX_device_group>>
extension on VK_KHX_device_group_creation to +vk.xml+ and the extension
appendix.
* Change the copyright on Vulkan specification asciidoc *source* files to
CC-BY 4.0, and update the proprietary Khronos copyright applied to the
generated *output* formats (internal issue 327). This enables broader
re-use and modification of the Vulkan specification sources, while not
affecting the Reciprocal IP License between Vulkan Adopters and Working
Group Members.
New Extensions:
* `VK_NV_fill_rectangle`
* `VK_NV_fragment_coverage_to_color`
* Bump API patch number and header version number to 51 for this update.
Github Issues:
* Add Valid Usage statement to flink:vkCmdResolveImage to require that
source and destination image formats match (public issue 492).
* Specify that a code:char* parameter must: be a valid null-terminated
string in the <<fundamentals-implicit-validity, implicit valid usage>>
section (public issue 494).
* Removed unnecessary VU for slink:VkPhysicalDeviceFeatures which is
covered by ename:VK_ERROR_FEATURE_NOT_PRESENT already (public issue
496).
* Clarify valid usage of pname:pQueueFamilyIndices in
slink:VkBufferCreateInfo, slink:VkImageCreateInfo, and
slink:VkSwapchainCreateInfoKHR (public issue 501).
* Document that dependencies of enabled extensions must also be enabled in
the <<extended-functionality-extensions-dependencies, Extension
Dependencies>> section (public issue 507).
Internal Issues:
* Change slink:VkMappedMemoryRange valid usage to allow pname:offset +
pname:size == size of the allocation. Also, if ename:VK_WHOLE_SIZE is
used, require the end of the mapping to be aligned to a multiple of
pname:nonCoherentAtomSize (internal issue 611).
* Add issue to `VK_KHR_win32_surface` about reusing window objects from a
different graphics API or Vulkan ICD (internal issue 639).
* Require locations on user in/out in `GL_KHR_vulkan_glsl` (internal issue
783).
* Added version info to the json validation output, and updated the schema
to match (internal issue 838).
* Restructure enumerated type descriptions separately from the command or
structure they are used in, allowing better reference page generation
(internal issue 841).
* Re-sort extension appendices to be in alphabetical order within each
author ID section.
* Fix enum naming and clarify behavior for
`VK_NVX_device_generated_commands` extension.
New Extensions:
* Bump API patch number and header version number to 50 for this update.
Github Issues:
* Fix numerous minor issues with the VK_EXT_debug_report extension (public
issues 478, 483, 486, 489, 490).
Internal Issues:
* Update flink:vkAllocateDescriptorSets to specify conditions under which
to return ename:VK_ERROR_FRAGMENTED_POOL or
ename:VK_ERROR_OUT_OF_POOL_MEMORY instead of
out-of-host/out-of-device-memory, and improve the
<<fundamentals-errorcodes, description of those errors (internal issue
654).
* Add a NOTE documenting that flink:vkAcquireNextImageKHR can only signal
a single semaphore, and how to deal with that when multiple physical
devices in a logical device need to wait on it (internal issue 730).
* Improve description of pname:pNext chains of
slink:VkPhysicalDeviceImageFormatInfo2KHR and
slink:VkImageFormatProperties2KHR (internal issue 814).
* Clean up math markup issues in the <<textures, Image Operations>>
chapter (internal issue 818).
* Update validusage target to use more robust code for preprocessing, by
making direct use of Asciidoctor's preprocessor. Added uniqueItems check
to JSON vu schema and add clean_validusage target (internal issue 826).
* Update style guide to prohibit writing non-self-contained (on a single
bullet point) Valid Usage statements, and modify offending Valid Usage
statements in the Specification to match, to assist with automatic
extraction for the validation layers (internal issue 828).
* Add ename:VK_VALIDATION_CHECK_SHADERS_EXT to elink:VkValidationCheckEXT
of the `VK_EXT_validation_flags` extension, to selectively disable
shader validation.
* Remove duplicate valid usage statement for slink:VkImageMemoryBarrier.
* Modify reflow.py script to place VUID tag anchors standalone on a line
following their corresponding bullet point, and reflow the spec text
accordingly (this had been pending since the initial tag deployment).
New Extensions:
* `VK_AMD_texture_gather_bias_lod`
* Bump API patch number and header version number to 49 for this update.
Github Issues:
* Modify reference page extraction script to make internal links to spec
anchors refer to the core specification instead of being dangling links
(public issue 455).
* Fix GL_KHR_vulkan_glsl typo and add a nor-normative mapping to the newly
published StorageBuffer class (public issue 466).
* Both flink:vkEnumerateInstanceExtensionProperties and
flink:vkEnumerateDeviceExtensionProperties return
ename:VK_ERROR_LAYER_NOT_PRESENT, which covers the error case of an
application providing a layer name that wasn't returned by
ftext:vkEnumerate{Instance|Device}LayerProperties (public issue 487).
* The specification for flink:VkApplicationInfo::apiVersion says that the
driver must return ename:VK_ERROR_INCOMPATIBLE_DRIVER in the case that
pname:apiVersion specifies a non-supported version. That means that the
valid usage should not also state that, and so the VU statement is
removed. The VU had language about "`an effective substitute`" that
would have been lost, and so it was moved to the pname:apiVersion
description (public issue 488).
Internal Issues:
* Modify implicit validity generator script to assign asciidoc anchors to
all valid usage statements it generates, and reflow.py script to insert
Valid Usage ID (VUID) tags into the specification source files for
explicit valid usage statements. This has no semantic effects on the
specification, but will support the validation layer's detection of
valid usage violations and allow it to link into the corresponding part
of the specification (internal issue 583).
* Assign VUID tags to all explicit VU statements and document
the process and tag format in the style guide (internal issue 583).
* Clarify the rules of whether to structure new functionality as instance
extensions, device extensions, or both in the
<<extended-functionality-instance-extensions-and-devices, Instance
Extensions and Device Extensions>> section (internal issue 749).
* Require that SPIR-V run-time arrays are only used with the
code:BufferBlock decoration (internal issue 750).
* Fix implicit and explicit valid usage statements for
slink:VkWriteDescriptorSet::pname:dstSet (internal issue 767)
* Fix SPIR-V code sample for ename:VK_DESCRIPTOR_TYPE_UNIFORM_TEXEL_BUFFER
in the <<descriptorsets-uniformtexelbuffer, Uniform Texel Buffer>>
section (internal issue 770).
* Clarify that disabling depth testing also disables depth writes in the
<<fragops-ds-state, Depth and Stencil Operations>> section (internal
issue 775).
* flink:VkDescriptorImageInfo::pname:imageLayout must match the actual
imageLayout at the time the image is accessed. This was in the spec
text, but needed an associated valid usage statement.
* Note that only 32-bit atomic operations are supported in the
<<spirvenv-module-validation, Validation Rules within a Module>>
section.
* Note that code:UniformConstant variables must not have initializers in
the <<spirvenv-module-validation, Validation Rules within a Module>>
section.
* Add a new elink:VkObjectType enumeration to the core API, promoted from
elink:VkDebugObjectTypeEXT, since it is used for much more than just the
debug_report extension.
New Extensions:
* `VK_KHR_get_surface_capabilities2`
* `VK_KHR_shared_presentable_image`
* Bump API patch number and header version number to 39 for this update.
Github Issues:
* Clarified that only accesses via the specified buffer/image subresource
ranges are included in the access scopes (public issue 306).
* Add missing valid usage statements for flink:vkCreateComputePipelines
and flink:vkCreateGraphicsPipelines (public issue 427).
Internal Issues:
* Add a Note to the <<invariance,Invariance>> appendix about a difference
between OpenGL and Vulkan with regards to how primitives derived from
offsets are handled (internal issue 355).
* Add the +<<VK_KHR_get_physical_device_properties2>>+,
+<<VK_KHR_maintenance1>>+, and +<<VK_KHR_shader_draw_parameters>>+
extensions (internal issue 448).
* Add the +<<VK_EXT_shader_subgroup_vote>>+ and
+<<VK_EXT_shader_subgroup_ballot>>+ extensions (internal issue 449).
* Update the texture level-of-detail equation in the
<<textures-scale-factor,Scale Factor Operation>> section to better
approximate the ellipse major and minor axes (internal issue 547).
* Forbid non-explicitly allowed uses of interface decorations in the
introduction to the <<interfaces,Shader Interfaces>> chapter (internal
issue 607).
* Replace use of MathJax with KaTeX, for improved load-time performance as
well as avoiding the scrolling-and-scrolling behavior due to MathJax
asynchronous rendering when loading at an anchor inside the spec. This
change also requires moving to HTML5 output for the spec instead of
XHTML, and there is a visible difference in that the chapter navigation
index is now in a scrollable sidebar instead of at the top of the
document. We may or may not retain the nav sidebar based on feedback
(internal issue 613).
* Improve consistency of markup and formatting in extension appendices
(internal issue 631).
Other Issues:
* Add explicit valid usage statements to slink:VkImageCopy requiring that
the source and destination layer ranges be contained in their respective
source and destination images.
* Add valid usage language for swapchain of flink:vkAcquireNextImage. If
the swapchain has been replaced, then it should not be passed to
flink:vkAcquireNextImage.
* Add a valid usage statement to flink:vkCreateImageView, that the image
must have been created with an appropriate usage bit set.
* Noted that slink:VkDisplayPresentInfoKHR is a valid extension of
slink:VkPresentInfoKHR in the <<wsi_swapchain,WSI Swapchain>> section.
* Update valid usage for flink:vkCmdSetViewport and flink:vkCmdSetScissor
to account for the multiple viewport feature. If the feature is not
enabled, the parameters for these functions have required values that
are defined in the <<features-features-multiViewport,multiple
viewports>> section of the spec but were not reflected in the valid
usage text for these functions.
* Add the +<<VK_EXT_swapchain_colorspace>>+ extension defining common
color spaces.
* Bump API patch number and header version number to 34 for this update.
Github Issues:
* Allow vkUpdateDescriptorSets overflow to skip empty bindings. Clarify
that unused bindings have a descriptorCount of zero. Improve some valid
usage for vkUpdateDescriptorSets (public issue 256).
* Require that slink:VkImageSubresourceRange always define a non-empty
range of the resource (public issue 303).
* Added valid usage for slink:VkPresentInfoKHR on the layout of presented
images (public issue 397).
Internal Issues:
* Add dependency in src/spec/Makefile so specversion.txt is regenerated
when needed (internal issue 462).
* Shorten the table of contents in the single-page ref page HTML output.
Still working on the PDF (internal issue 536).
* Bump API patch number and header version number to 29 for this update.
Github Issues:
* Remove redundant constraint on
slink:VkCommandBufferInheritanceInfo::pname:queryFlags (public issue
224).
* Fix typo and remove link in Note in the
<<extended-functionality-instance-extensions-and-devices, Instance
Extensions and Device Extensions>> section (public issue 359).
* Fix erroneous validation statement for the pname:layout member of
slink:VkComputePipelineCreateInfo (public issue 362).
Internal Issues:
* Restore long figure captions using asciidoc sidebar blocks, due to
restrictions of asciidoc syntax (internal issue 101).
* Replace most latexmath equations with comparable markup in straight
asciidoc, which significantly improves time required to fully load and
process the HTML forms of the Specification. There are known minor font
and alignment inconsistencies with MathJax and PDF rendering of
latexmath equations. Please do not file github issues about these. We
are aware of the inconsistencies and will make refinements over time,
while the performance improvements are compelling in at least some major
browsers (internal issue 313).
* Move handcoded validity statements from +vk.xml+ into the Specification
body, easing work in the single-branch model. Specify the distinction
between these explicit statements, and the implicit validity statements
inferred from vk.xml. Validity statements now appear in two blocks for
each command and structure - handcoded "Valid Usage" and the implicit
"Valid Usage (Implicit)" (internal issue 392).
* Add the +returnedonly="false"+ attribute to WSI output structures,
removing incorrectly generated implicit validity statements for
slink:VkDisplayPropertiesKHR, slink:VkDisplayPlanePropertiesKHR,
slink:VkDisplayModePropertiesKHR, slink:VkDisplayPlaneCapabilitiesKHR,
slink:VkSurfaceCapabilitiesKHR, and slink:VkSurfaceFormatKHR structures
(internal issue 486).
* Update slink:VkImageLayout to require the
ename:VK_IMAGE_USAGE_SAMPLED_BIT be set for sampled depth/stencil images
(internal issue 487).
* Use an explicit format specifier string for the date command invocation
in the +Makefile+ instead of the shorthand -R option, which doesn't work
on BSD and MaxOS X date commands (internal issue 500).
Other Issues:
* Use the terms ``allocation scope'' and ``extension scope'' instead of
just ``scope'', and add them to the glossary.
* Bump API patch number and header version number to 27 for this update.
Github Issues:
* Weaken flink:vkGetPipelineCacheData invariance conditions; previous
conditions were stronger than agreed and can't be guaranteed (public
issue 280).
* Add link to "Vulkan Loader Specification and Architecture Overview"
document to Normative References section (public issue 359).
Internal Issues:
* Be more clear in the <<interfaces-resources-layout-std140, uniform
buffer layout>> section that block offsets can be out of order
(internal issue 396).
* Document that extension authors should add support for their extensions
to the validation layers (internal issue 398).
* Clarify that the valid range of depth clear values should be limited
to the 0..1 range and that copies to depth aspect must also be in this
range (internal issue 412).
* Specify ``a'' vs. ``an'' use in the style guide (internal issue 432).
* Increase the maximum pname:nonCoherentAtomSize value in the
<<features-limits-required,Required Limits>> section from 128 to 256
(internal issue 435).
* Fix vk_platform.h for compiler errors on some Android platforms
(internal issue 441).
* Clarify that slink:VkPhysicalDeviceFeatures::pname:pEnabledFeatures ==
`NULL` disables all features, including the "required" feature
pname:robustBufferAccess (internal issue 479).
Other Issues:
* Expand style guide and make it more self-consistent.
* Use ISO 8601 date format everywhere.
* Emphasise the correct way of using
slink:VkSurfaceCapabilitiesKHR::pname:maxImageCount.
* Added +VK_EXT_validation_flags+ extension for validation flag mechanism.
* Fix an <<credits,author credit>> to include their current employer.
Jon Leech