* 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.
* Bump API patch number and header version number to 21 for this update.
Github Issues:
* Clarify how <<features-supported-sample-counts,sample count queries>>
relate to the limits in slink:VkPhysicalDeviceLimits. (public issue
185).
* Clarify in the <<interfaces-iointerfaces,Shader Input and Output
Interfaces>> section that shader output variables have undefined values
until the shader writes to them (public issue 240).
* Specify the implicit value of image parameters that cannot be set in
slink:VkSwapchainCreateInfo::pname:flags, pname:imageType,
pname:mipLevels, pname:samples, pname:tiling, and pname:initialLayout
(public issue 243).
* Make use of code:NULL and code:VK_NULL_HANDLE consistent in the
VK_KHR_swapchain extension (public issue 276).
Internal Issues:
* Clarify that presenting an image to a display surface swapchain applies
the display surface's mode, and that destroying a display surface
swapchain may reset the display's mode, in the VK_KHR_display_swapchain
extension (internal issue 247).
* Better describe what a slink:VkSurfaceKHR is, and that creating one does
not set a mode, in the VK_KHR_display extension. This is a round-about
way of pointing out that mode setting is not covered by the extension,
but rather is performed as a side effect of presentation (internal issue
247).
* Add more valid usage statements to flink:vkQueuePresentKHR command when
the VK_KHR_display_swapchain extension is present (internal issue
247).
* Add more includes to the VK_KHR_swapchain extension to better document
interactions with VK_KHR_display_swapchain (internal issue 247).
* Clarify restrictions on location aliasing in the
<<fxvertex,Fixed-Function Vertex Processing>> section (internal issue
370).
* Add mathematical description of blitting to flink:vkCmdBlitImage, and
link it to the <<textures,Image Operations>> chapter. Use mathematical
notation for ranges of texel coordinates in the <<textures,Image
Operations>> chapter. Fixed miscellaneous validity statements for
flink:vkCmdBlit and slink:VkImageBlit (internal issue 382).
Other Commits:
* Added a valid usage rule to flink:VkGraphicsPipelineCreateInfo that the
ename:VK_PRIMITIVE_TOPOLOGY_PATCH_LIST topology must only be used when
tessellation shaders are used.
* Expand the style guide into a formal "Procedures and Conventions"
document. Add a API Naming Conventions section, move most of the API
Specification Appendix C (Layers and Extensions) content into the new
document, and define the resulting procedures as mandatory (where
relevant). This more clearly separates use vs. specification of Vulkan
APIs.
* Update vk_platform.h to handle 32-bit ARMv8 binaries.
* Various minor cleanups to the Makefile and build process.
