* Bump API patch number and header version number to 60 for this update.
Github Issues:
* Document that <<queries-timestamps, Timestamp Queries>> can only be
meaningfully compared when they are written from the same queue (public
issue 216).
* Document that the `<extension>` tag `type` attribute is required for
non-disabled extensions (derived from, but does not close public issue
354).
* Clean up registry schema length attribute descriptions to be consistent
and correct (public issue 555).
Internal Issues:
* Replace as much of the hand-written extension appendix metadata as
possible with asciidoc includes generated from corresponding attributes
of +vk.xml+, and enhance the style guide to match. This avoids
inconsistencies between +vk.xml+ and the appendices, and produces a more
uniform style (internal issue 137).
* Remove the generated extDependency.{py,sh} files from the tree and
create them dynamically on demand instead, reducing merge conflicts
(internal issue 713).
* Add a prototype tool for generating in-place difference markup for
sections guarded by asciidoc conditionals, and new syntax for open
blocks to support it (internal issue 833).
* Remove unnecessary restriction of etext:*SYNC_FD_BIT_KHR external handle
types to the same physical device in the
slink:VkPhysicalDeviceIDPropertiesKHR,
flink:VkImportMemoryWin32HandleInfoKHR,
slink:VkImportFenceWin32HandleInfoKHR, slink:VkImportFenceFdInfoKHR,
slink:VkImportSemaphoreWin32HandleInfoKHR,
slink:VkImportSemaphoreFdInfoKHR
<<external-memory-handle-types-compatibility, External memory handle
types compatibility>>, <<external-semaphore-handle-types-compatibility,
External semaphore handle types compatibility>>, and
<<external-fence-handle-types-compatibility, External fence handle types
compatibility>> sections (internal issue 956).
Other Issues:
* Remove dependency of +VK_KHX_device_group+ on +VK_KHR_swapchain+ (there
is an interaction, but not a strict dependency), and add a new
`extension` attribute to the `<require` XML tag to allow classifying a
subset of interfaces of an extension as requiring another extension.
Update the registry schema and documentation accordingly.
New Extensions:
* `VK_AMD_shader_fragment_mask` (and related `GL_AMD_shader_fragment_mask`
GLSL extension)
* `VK_EXT_sample_locations`
* `VK_EXT_validation_cache`
* Bump API patch number and header version number to 42 for this update
(the first anniversary edition).
Github Issues:
* Changed asciidoctor macros so cross-page links in the standalone
reference pages function properly (public issue 462).
Internal Issues:
* Clarified host visibility discussion for slink:VkMemoryType,
flink:vkInvalidateMappedMemoryRanges, elink:VkAccessFlagBits, and the
<<synchronization-framebuffer-regions,Framebuffer Region Dependencies>>
section, removing duplicated information and adding a central definition
in the access types section (internal issue 552).
* Change description of
slink:vkGetPhysicalDeviceSurfacePresentModesKHR::pname:pPresentModes to
return an array of values, not structures (internal issue 699).
New Extensions:
* Add a NOTE to the <<extensions,Layers & Extensions>> chapter describing
the experimental status of `KHX` extensions.
* Add new Khronos, Khronos Experimental, and vendor Vulkan extensions for
release at GDC:
** VK_KHR_descriptor_update_template
** VK_KHR_push_descriptor
** VK_KHX_device_group
** VK_KHX_device_group_creation
** VK_KHX_external_memory
** VK_KHX_external_memory_capabilities
** VK_KHX_external_memory_fd
** VK_KHX_external_memory_win32
** VK_KHX_external_semaphore
** VK_KHX_external_semaphore_capabilities
** VK_KHX_external_semaphore_fd
** VK_KHX_external_semaphore_win32
** VK_KHX_multiview
** VK_KHX_win32_keyed_mutex
** VK_EXT_discard_rectangles
** VK_MVK_ios_surface
** VK_MVK_macos_surface
** VK_NVX_multiview_per_view_attributes
** VK_NV_clip_space_w_scaling
** VK_NV_geometry_shader_passthrough
** VK_NV_sample_mask_override_coverage
** VK_NV_viewport_array2
** VK_NV_viewport_swizzle
* Add new GLSL vendor extensions to support new builtin variables:
** GL_EXT_device_group
** GL_EXT_multiview
Jon Leech