* Update release number to 91.
Public Issues:
* Update Ubuntu subsystem build instructions in `BUILD.adoc` (public pull
request 624).
* Delete the `VK_KHR_mir_surface` extension from the Specification and
XML, due to EOL of the only driver known to have supported it, and
near-EOL of Mir itself (public issue 814).
* Fix options for some figures that were using old ones (public pull
request 841).
* Fix various accidentally repeated words (public pull request 843).
* Use `time.process_time()`, introduced in Python 3.3, in the scripts
instead of `time.clock()`, which will be removed in Python 3.8 (public
pull request 844).
Internal Issues:
* Update valid usage statements for
`VK_ANDROID_external_memory_android_hardware_buffer` in
slink:VkMemoryAllocateInfo,
slink:VkImportAndroidHardwareBufferInfoANDROID, and
flink:vkGetAndroidHardwareBufferPropertiesANDROID to actually be
verifiable (internal issue 1419).
* Update valid usage statements for
`VK_ANDROID_external_memory_android_hardware_buffer` in
slink:VkMemoryAllocateInfo, slink:VkImageCreateInfo, and
slink:VkImageViewCreateInfo to move valid usage statements in
doubly-nested bullet points up one level, accomodating limitations of
the valid usage extraction script that creates `validusage.json`
(internal issue 1434).
* Fix typo etext:VK_ACCESS_SHADING_RATE_IMAGE_BIT_NV to the correct
ename:VK_ACCESS_SHADING_RATE_IMAGE_READ_BIT_NV.
* Add missing etext:VK_STRUCTURE_TYPE_* tokens to appendices for
extensions missing them.
New Extensions:
* `VK_AMD_memory_overallocation_behavior`
* `VK_NV_ray_tracing`, replacing `VK_NVX_raytracing`
* Update release number to 85.
Public Issues:
* Add self-dependency ename:VK_DEPENDENCY_BY_REGION_BIT valid usage
statements for slink:VkSubpassDependency(public pull request 778).
* Apply fix from pull request 742 to slink:VkSubpassDependency and
slink:VkSubpassDependency2 (public pull request 779).
* Specify the units of slink:VkBufferImageCopy::pname:bufferRowLength and
pname:bufferImageHeight as texels (public pull request 781).
* Better specify promoted parameter mapping in the
`<<VK_KHR_create_renderpass2>>` appendix (public pull request 782).
Internal Issues:
* Only include the <<fundamentals-validusage-versions, Valid Usage for
Newer Core Versions>> section in Vulkan 1.1 or later (internal issue
1381).
Other Issues:
* Clean up redundant valid usage language for the
`VK_ANDROID_external_memory_android_hardware_buffer` extension
interaction with slink:VkImageCreateInfo.
* Fix error in a flag name within valid usage statements for
slink:VkMemoryAllocateInfo.
* Clarify that memory types are not totally ordered in
slink:VkPhysicalDeviceMemoryProperties.
* For slink:VkWriteDescriptorSetInlineUniformBlockEXT, set
structextends="VkWriteDescriptorSet" in `vk.xml`, and make
slink:VkDescriptorSetLayoutBindingFlagsCreateInfoEXT::pname:pBindingFlags
optional.
* Add documentation of 'provisional' XML attribute to registry.txt.
New Extensions:
* `VK_NV_compute_shader_derivatives`
* `VK_NV_corner_sampled_image`
* `VK_NV_fragment_shader_barycentric`
* `VK_NV_mesh_shader`
* `VK_NV_representative_fragment_test`
* `VK_NV_scissor_exclusive`
* `VK_NV_shader_image_footprint`
* `VK_NV_shading_rate_image`
* `VK_NVX_raytracing`