* Update release number to 122.
Internal Issues:
* Add style guide language on not using standalone `+` signs (internal
issue 736); not using leading whitespace for markup (internal issue
747); and on keeping descriptions of a single API in a contiguous block
of markup (internal issue 949), and apply them to the specification.
* Add a glossary definition of "`constant integral expression`", pointing
to the SPIR-V "`constant instruction`" definition (internal issue 1225).
* Many minor edits to improve writing style consistency and capture
additional style guidelines (internal issue 1553).
* Clarify that <<fragops-depth-write, depth writes are not performed>> if
there is no depth framebuffer attachment (internal issue 1771).
* Allow implementations to use rectangular line style of interpolation for
<<primsrast-lines-bresenham, wide Bresenham lines>>, though replicating
attributes is still preferred. Clarify that code:FragCoord is not
replicated (internal issue 1772).
* Resolve a contradiction in valid usage statements for
slink:VkImageCreateInfo and slink:VkImageStencilUsageCreateInfoEXT
(internal issue 1773).
* Add style guide discussion of markup for indented equations, and use
markup workaround for asciidoctor 2 compatibility (internal issue 1793).
* Deprecate the `<<VK_EXT_validation_flags>>` extension in `vk.xml` and
the extension appendix (internal issue 1801).
* Add a new checker script `scripts/xml_consistency.py`. This is not
currently run as part of internal CI (internal merge request 3285).
* Correct "`an`" -> "`a`" prepositions where needed (internal merge
request 3334).
* Clarify that the <<features-uniformBufferStandardLayout,
pname:uniformBufferStandardLayout>> feature is only required when the
extension defining it is supported (internal merge request 3341).
* Bring scripts into closer sync with OpenXR, mainly through conversion of
comments to docstrings where appropriate, and add gen-scripts-docs.sh
(internal merge request 3324).
* Correct pname:maxDrawMeshTasksCount to 2^16^-1 in the <<limits-required,
Required Limits>> table (internal merge requests 3361).
New Extensions
* `<<VK_IMG_format_pvrtc>>` (public issue 512).
* Update release number to 80.
Public Issues:
* Remove unused "`API Order`" term from glossary (public issue 657).
* Dynamically generate the extension appendix includes based on
information in `vk.xml`, including new metadata tags describing
deprecated, obsoleted, and promoted extensions (public pull request
690).
Internal Issues:
* Add valid usage statements to flink:vkCmdBindDescriptorSets to keep
offsets + range less than or equal to the buffer size (internal issue
1174).
New Extensions:
* `VK_EXT_conditional_render`
* `VK_KHR_create_renderpass2` (public issue 736)
* `VK_KHR_8bit_storage` (public issue 737)
- hide from toc
- split into "current" extensions, and extensions that have been since
deprecated by a better alternative
- make core promotion list generated
- add information to extension appendix about possible better
alternatives
- split contacts to separate lines
- some general-purpose quality improvements to the script
