Change log for July 3, 2020 Vulkan 1.2.146 spec update:

  * Update release number to 146 for this update.

Github Issues:

  * Fix valid usage generation script for optional bitmasks in a
    non-optional array (public pull request 1228).
  * Add lunr to `package.json` and update the locally cached copy (public
    pull request 1238).
  * Require that newly released extensions have etext:*_SPEC_VERSION `1`
    (public issue 1263).
  * Add to the NOTE in slink:VkPhysicalDeviceIDProperties, advising
    implementations on returning unique pname:deviceUUID values and avoiding
    hardwired values, especially 0 (public issue 1273).
  * Add noscript fallback for HTML output (public pull request 1289).
  * Fix duplicated VUIDs in flink:vkCmdExecuteGeneratedCommandsNV (public
    pull request 1304).
  * Fix link markup in <<ray-traversal, Ray Traversal>> chapter, nested link
    markup, and linear equation markup in
    <<textures-unnormalized-to-integer>> (public pull requests 1305, 1306,
    1307).

Internal Issues:

  * Add comments to extending enums in the generated API interfaces showing
    which core version and/or extensions provide the enum, matching recent
    changes to show this information for commands and structures (internal
    issue 1431).
  * Only allow code:Invocation memory scope in the
    <<spirvenv-module-validation-standalone, Standalone SPIR-V Validation>>
    section when memory semantics is *None* (internal issue 1782).
  * Make reflow script handle literal block delimiters and lines containing
    only whitespace properly (internal issues 2039, 2042).
  * Clarify definition of <<limits-maxFragmentCombinedOutputResources,
    pname:maxFragmentCombinedOutputResources>> (internal issue 2236).
  * Add missing `errorcodes=` XML attributes for some
    `<<VK_EXT_display_control>>` commands.
  * Clarify <<features-extentperimagetype, allowed extent values based on
    image type>> and the related <<limits-maxImageDimension1D>>,
    <<limits-maxImageDimension2D>>, <<limits-maxImageDimension3D>>,
    <<limits-maxImageDimensionCube>> limits (internal merge request 3922).
  * Remove redundant valid usage statement
    VUID-VkFramebufferCreateInfo-flags-03188 (internal merge request 3934).
  * Update style guide to recommend new extension spec language be contained
    in existing asciidoctor files, unless it's of enough scope to create a
    and new chapter (internal merge request 3955).

New Extensions:

  * `<<VK_EXT_directfb_surface>>` (public pull requests 1292, 1294).
  * `<<VK_EXT_fragment_density_map2>>` (internal merge request 3914).

appendices/VK_EXT_fragment_density_map2.txt

@@ -0,0 +1,118 @@
+// Copyright (c) 2020 The Khronos Group Inc.
+//
+// SPDX-License-Identifier: CC-BY-4.0
+
+include::{generated}/meta/VK_EXT_fragment_density_map2.txt[]
+
+*Last Modified Date*::
+    2020-06-16
+*Interactions and External Dependencies*::
+  - Interacts with Vulkan 1.1
+*Contributors*::
+  - Matthew Netsch, Qualcomm Technologies, Inc.
+  - Jonathan Tinkham, Qualcomm Technologies, Inc.
+  - Jonathan Wicks, Qualcomm Technologies, Inc.
+  - Jan-Harald Fredriksen, ARM
+
+This extension adds additional features and properties to
+`<<VK_EXT_fragment_density_map>>` in order to reduce fragment density map
+host latency as well as improved queries for subsampled sampler
+implementation-dependent behavior.
+
+=== New Object Types
+
+None.
+
+=== New Enum Constants
+
+  * Extending elink:VkImageViewCreateFlagBits:
+  ** ename:VK_IMAGE_VIEW_CREATE_FRAGMENT_DENSITY_MAP_DEFERRED_BIT_EXT
+  * Extending elink:VkStructureType:
+  ** ename:VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FRAGMENT_DENSITY_MAP_2_FEATURES_EXT
+  ** ename:VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FRAGMENT_DENSITY_MAP_2_PROPERTIES_EXT
+
+=== New Enums
+
+None.
+
+=== New Structures
+
+  * slink:VkPhysicalDeviceFragmentDensityMap2FeaturesEXT
+  * slink:VkPhysicalDeviceFragmentDensityMap2PropertiesEXT
+
+=== New Functions
+
+None.
+
+=== New Variable Decorations
+
+None.
+
+=== Version History
+
+ * Revision 1, 2020-06-16 (Matthew Netsch)
+   - Initial version
+
+ifdef::isrefpage[]
+=== Examples
+
+==== Additional limits for subsampling
+
+Some implementations may not support subsampled samplers if certain
+implementation limits are not observed by the app.
+slink:VkPhysicalDeviceFragmentDensityMap2PropertiesEXT provides additional
+limits to require apps remain within these boundaries if they wish to use
+subsampling.
+
+==== Improved host latency
+
+By default, the fragment density map is locked by the host for reading
+between flink:vkCmdBeginRenderPass during recording and
+ename:VK_PIPELINE_STAGE_FRAGMENT_DENSITY_PROCESS_BIT_EXT during draw
+execution.
+
+This can introduce large latency for certain use cases between recording the
+frame and displaying the frame.
+Apps may wish to modify the fragment density map just before draw execution.
+
+ename:VK_IMAGE_VIEW_CREATE_FRAGMENT_DENSITY_MAP_DEFERRED_BIT_EXT is intended
+to help address this for implementations that do not support the
+<<features-fragmentdensitymapdynamic,fragmentDensityMapDynamic>> feature by
+deferring the start of the locked range to flink:vkEndCommandBuffer.
+
+
+[source,c++]
+----------------------------------------
+// Create view for fragment density map
+VkImageViewCreateInfo createInfo =
+{
+   ​VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO,
+   // ...
+   VK_IMAGE_VIEW_CREATE_FRAGMENT_DENSITY_MAP_DEFERRED_BIT_EXT,
+   fdmImage, // Created with VK_IMAGE_USAGE_FRAGMENT_DENSITY_MAP_BIT_EXT
+   // ...
+};
+
+// ...
+
+// Begin fragment density map render pass with deferred view.
+// By default, fdmImage must not be modified after this call
+// unless view is created with the FDM dynamic or deferred flags.
+vkCmdBeginRenderPass(commandBuffer, pRenderPassBegin, contents);
+
+// ...
+
+vkCmdEndRenderPass(VkCommandBuffer commandBuffer);
+
+// Can keep making modifications to deferred fragment density maps
+// while recording commandBuffer ...
+
+result = vkEndCommandBuffer(commandBuffer);
+
+// Must now freeze modifying fdmImage until after the
+// VK_PIPELINE_STAGE_FRAGMENT_DENSITY_PROCESS_BIT_EXT of
+// the last executing draw that uses the fdmImage in the
+// last submit of commandBuffer.
+
+----------------------------------------
+endif::isrefpage[]

config/vuid-expander.rb

@@ -0,0 +1,21 @@
+# Copyright 2020 The Khronos Group Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+require 'asciidoctor/extensions' unless RUBY_ENGINE == 'opal'
+
+include ::Asciidoctor
+
+# Preprocessor hook to insert vuid: inline macro after every VUID anchor
+class VUIDExpanderPreprocessor < Extensions::Preprocessor
+  def process document, reader
+    new_lines = reader.read_lines.map do | line |
+      line.gsub(/\[\[(VUID.*?)\]\]/, '[[\1]]vuid:\1')
+    end
+    Reader.new(new_lines)
+  end
+end
+
+Extensions.register do
+  preprocessor VUIDExpanderPreprocessor
+end

scripts/testSpecVersion.py

@@ -0,0 +1,71 @@
+#!/usr/bin/python3
+#
+# Copyright (c) 2017-2020 The Khronos Group Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# testSpecVersion - check if SPEC_VERSION values for an unpublished
+# extension branch meet the requirement of being 1.
+#
+# Usage: textSpecVersion.py [-branch branchname] [-registry file]
+#
+# Checks for an XML <extension> matching the branch name specified
+# on the command line, or the current branch if not specified.
+#
+# If found, and the SPEC_VERSION for that <extension> has a value of '1', #
+# of '1', succeeds.
+# If not found, the branch is not an extension staging branch; succeeds.
+
+# Otherwise, fails.
+
+import argparse
+import sys
+import xml.etree.ElementTree as etree
+from reflib import getBranch
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('-branch', action='store',
+                        default=None,
+                        help='Specify branch to check against')
+    parser.add_argument('-registry', action='store',
+                        default='xml/vk.xml',
+                        help='Use specified registry file instead of vk.xml')
+    args = parser.parse_args()
+
+    try:
+        tree = etree.parse(args.registry)
+    except:
+        print('ERROR - cannot open registry XML file', args.registry)
+        sys.exit(1)
+
+    errors = ''
+    if args.branch is None:
+        (args.branch, errors) = getBranch()
+    if args.branch is None:
+        print('ERROR - Cannot determine current git branch:', errors)
+        sys.exit(1)
+
+    elem = tree.find('extensions/extension[@name="' + args.branch + '"]')
+
+    if elem == None:
+        print('Success - assuming', args.branch, 'is not an extension branch')
+        sys.exit(0)
+
+    for enum in elem.findall('require/enum'):
+        name = enum.get('name')
+
+        if name is not None and name[-13:] == '_SPEC_VERSION':
+            value = enum.get('value')
+            if value == '1':
+                print('Success - {} = 1 for branch {}'.format(
+                      name, args.branch))
+                sys.exit(0)
+            else:
+                print('ERROR - {} = {} for branch {}, but must be 1'.format(
+                      name, value, args.branch))
+                sys.exit(1)
+
+    print('ERROR - no SPEC_VERSION token found for branch', args.branch)
+    sys.exit(1)