MoltenVK Documentation

File: README.md

MoltenVK

Introduction to MoltenVK
Developing Vulkan Applications on macOS, iOS, tvOS, and visionOS
- Using the Vulkan SDK
- Using MoltenVK Directly
Fetching MoltenVK Source Code
Building MoltenVK
Running MoltenVK Demo Applications
Using MoltenVK in Your Application
MoltenVK and Vulkan Compliance
Getting Support
Contributing to MoltenVK Development

Introduction to MoltenVK

MoltenVK is a layered implementation of Vulkan 1.4
graphics and compute functionality, that is built on Apple's Metal
graphics and compute framework on macOS, iOS, tvOS, and visionOS. MoltenVK allows
you to use Vulkan graphics and compute functionality to develop modern, cross-platform,
high-performance graphical games and applications, and to run them across many platforms,
including macOS, iOS, tvOS, visionOS, Simulators, and Mac Catalyst,
and all Apple architectures, including Apple Silicon.

Metal uses a different shading language, the Metal Shading Language (MSL), than
Vulkan, which uses SPIR-V. MoltenVK automatically converts your SPIR-V shaders
to their MSL equivalents.

To provide Vulkan capability to the macOS, iOS, tvOS, and visionOS platforms,
MoltenVK uses Apple's publicly available API's, including Metal. MoltenVK
does not use any private or undocumented API calls or features, so your app will
be compatible with all standard distribution channels, including Apple's App Store.

The MoltenVK runtime package contains two products:

MoltenVK is a implementation of an almost-complete subset of the
Vulkan 1.4 graphics and compute API.
MoltenVKShaderConverter converts SPIR-V shader code to Metal Shading Language (MSL) shader code.
The converter is embedded in the MoltenVK runtime to automatically convert SPIR-V shaders
to their MSL equivalents. In addition, the SPIR-V converter is packaged into a stand-alone command-line
MoltenVKShaderConverter macOS tool for converting shaders at development time from the command line.

Developing Vulkan Applications for macOS, iOS, tvOS, and visionOS

Using the Vulkan SDK

The recommended method for developing a Vulkan application for macOS is to use the
Vulkan SDK.

The Vulkan SDK includes a MoltenVK runtime library for macOS. Vulkan is a layered
architecture that allows applications to add additional functionality without modifying the
application itself. The Validation Layers included in the Vulkan SDK are an essential debugging
tool for application developers because they identify inappropriate use of the Vulkan API.
If you are developing a Vulkan application for macOS, it is highly recommended that you use the
Vulkan SDK and the MoltenVK library included in it.
Refer to the Vulkan SDK Getting Started
document for more info.

Because MoltenVK supports the VK_KHR_portability_subset extension, when using the
Vulkan Loader from the Vulkan SDK to run MoltenVK on macOS, the Vulkan Loader
will only include MoltenVK VkPhysicalDevices in the list returned by
vkEnumeratePhysicalDevices() if the VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR
flag is enabled in vkCreateInstance(). See the description of the VK_KHR_portability_enumeration
extension in the Vulkan specification for more information about the use of the
VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR flag.

Using MoltenVK Directly

If you are developing a Vulkan application for iOS, tvOS, or visionOS, or are
developing a Vulkan application for macOS and want to use a different version or
build of the MoltenVK runtime library than provided in the macOS Vulkan SDK,
you can access a pre-built MoltenVK binary library from the MoltenVK repository, by
selecting a repository commit from the list,
and downloading the associated MoltenVK runtime library artifact.

Finally, if you want a customized build of MoltenVK, you can follow the instructions below
to create a MoltenVK runtime library by fetching and building the MoltenVK source code.

To learn how to integrate the MoltenVK runtime library into a game or application,
see the MoltenVK_Runtime_UserGuide.md
document in the Docs directory.

Fetching MoltenVK Source Code

To fetch MoltenVK source code, clone this MoltenVK repository, and then run the
fetchDependencies script to retrieve and build several external open-source libraries
on which MoltenVK relies:

Ensure you have cmake and python3 installed:
text
```
brew install cmake
 brew install python3
```
For faster dependency builds, you can also optionally install ninja:
text
```
brew install ninja
```

Clone the MoltenVK repository:

text

git clone https://github.com/KhronosGroup/MoltenVK.git

Retrieve and build the external libraries:
text
```
cd MoltenVK
 ./fetchDependencies [platform...]
```

When running the fetchDependencies script, you must specify one or more platforms
for which to build the external libraries. The platform choices include:

text

--all
--macos
--ios
--iossim
--maccat
--tvos
--tvossim

You can specify multiple of these selections. The result is a single XCFramework
for each external dependency library, with each XCFramework containing binaries for
each of the requested platforms.

The --all selection is the same as entering all of the other platform choices,
and will result in a single XCFramework for each external dependency library,
with each XCFramework containing binaries for all supported platforms and simulators.

Running fetchDependencies repeatedly with different platforms will accumulate targets
in the XCFramework, if the --keep-cache option is used on each invocation.

For more information about the external open-source libraries used by MoltenVK,
see the ExternalRevisions/README.md document.

Building MoltenVK

During building, MoltenVK references the latest Apple SDK frameworks. To access these frameworks,
and to avoid build errors, be sure to use the latest publicly available version of Xcode.

MoltenVK currently supports being built with Xcode 15.0.1 or later. Support is based on the
earliest version of Xcode that can be verified in CI workflows.

Once built, the MoltenVK libraries can be run on macOS, iOS, tvOS, or visionOS devices
that support Metal,or on the Xcode iOS Simulator, tvOS Simulator, or visionOS Simulator.

The minimum runtime OS versions are indicated in the Deployment Target build settings in MoltenVK.xcodeproj.
Information on macOS devices that are compatible with Metal can be found in
this article.
Information on iOS devices that are compatible with Metal can be found in
this article.

Building With _Xcode_

The MoltenVKPackaging.xcodeproj Xcode project contains targets and schemes to build
and package the entire MoltenVK runtime distribution package, or to build individual
MoltenVK or MoltenVKShaderConverter components.

To build a MoltenVK runtime distribution package, suitable for testing and integrating into an app,
open MoltenVKPackaging.xcodeproj in Xcode, and use one of the following Xcode Schemes, depending
on whether you want a Release or Debug configuration, and whether you want to build for all
platforms, or just one platform (in Release configuration):

MoltenVK Package
MoltenVK Package (Debug)
MoltenVK Package (macOS only)
MoltenVK Package (iOS only)
MoltenVK Package (tvOS only)
MoltenVK Package (visionOS only) (requires Xcode 15+)

Each of theseMoltenVKPackaging.xcodeproj Xcode project Schemes puts the resulting packages in the
Package directory, creating it if necessary. This directory contains separate Release and Debug
directories, holding the most recent Release and Debug builds, respectively.

Note: Due to technical limitations in the dynamic library build tools, dynamic frameworks and libraries cannot be created
for the tvOS Simulator, or MacCatalyst platforms. Static frameworks are created for these, and all other, platforms.

A separate Latest directory links to the most recent build, regardless of whether it was a Release
or Debug build. Effectively, the Package/Latest directory points to whichever of the Package/Release
or Package/Debug directories was most recently updated.

With this packaging structure, you can follow the instructions below to link your application
to the MoltenVK libraries and frameworks in the Package/Latest directory, to provide the flexibility
to test your app with either a Debug build, or a higher-performance Release build.

Building From the Command Line

If you prefer to build MoltenVK from the command line, or to include the activity in a larger build script,
you can do so by executing a command similar to the following command within the MoltenVK repository folder,
and identifying one of the Xcode Schemes from the list above. For example, the following command will build
MoltenVK in the Debug configuration for macOS only:

text

xcodebuild build -quiet -project MoltenVKPackaging.xcodeproj -scheme "MoltenVK Package (macOS only)" -configuration "Debug"

Alternately, you can use the basic Makefile in the MoltenVK repository folder to build MoltenVK
from the command line. The following make targets are provided:

text

make
make all
make macos
make ios
make iossim
make maccat
make tvos
make tvossim

make all-debug
make macos-debug
make ios-debug
make iossim-debug
make maccat-debug
make tvos-debug
make tvossim-debug

make clean
make install

Running make repeatedly with different targets will accumulate binaries for these different targets.
The all target executes all platform targets.
The all target is the default target. Running make with no arguments is the same as running make all.
The *-debug targets build the binaries using the Debug configuration.
The install target will copy the most recently built Package/Latest/MoltenVK/dynamic/dylib/macOS/libMoltenVK.dylib
into the /usr/local/lib system directory on your computer. Since /usr/local/lib is protected, you will generally
need to run it as sudo make install and enter your password. The install target does not build MoltenVK,
and you need to run make macos or make macos-debug first.

The make targets all require that Xcode is installed on your system.

Note: Due to technical limitations within Xcode, a dynamic framework is not created for the MacCatalyst platform.

Building from the command line creates the same Package folder structure described above when
building from within Xcode.

When building from the command line, you can set any of the build settings documented
in the MoltenVK_Configuration_Parameters.md file, by passing them in the command line,
as in the following examples:

text

make MVK_CONFIG_LOG_LEVEL=0

or
make macos MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS=1

...etc.

Hiding _Vulkan_ API Symbols

You can optionally build MoltenVK with the Vulkan API static call symbols (vk*) hidden, to avoid
library linking conflicts when statically bound to a Vulkan loader that also exports identical symbols.

To do so, when building MoltenVK, set the build setting MVK_HIDE_VULKAN_SYMBOLS=1.
This build setting can be set in the MoltenVK.xcodeproj Xcode project, or it can be
included in any of the make command-line build commands mentioned above.

With MVK_HIDE_VULKAN_SYMBOLS=1, the Vulkan vkGetInstanceProcAddr() call remains
statically bound, to provide the application with the ability to retrieve the remaining
Vulkan API calls as function pointers.

Accessing _Metal_ Private API Calls

You can optionally build MoltenVK with access to private Metal API calls, also known
as "Service Provider Interfaces" (SPIs). Doing so will allow MoltenVK to extend its
functionality by using certain private Metal API calls, but it will also disqualify the
app from being distributed via Apple App Stores.

To do so, when building MoltenVK, set the build setting MVK_USE_METAL_PRIVATE_API=1.
This build setting can be set in the MoltenVK.xcodeproj Xcode project, or it can be
included in any of the make command-line build commands mentioned above.

Functionality added with MVK_USE_METAL_PRIVATE_API enabled includes:

VkPhysicalDeviceFeatures::wideLines
VkPhysicalDeviceFeatures::logicOp
VkGraphicsPipelineRasterizationCreateInfo::sampleMask, using MTLRenderPipelineDescriptor.sampleMask instead of emulating it in the fragment shader

Install MoltenVK to Replace the _Vulkan SDK_ `libMoltenVK.dylib`

To replace the version of the MoltenVK installed on macOS via the
Vulkan SDK standard install process,
perform the following steps:

Build a macOS version of MoltenVK, as described above.
The default config for command-line MoltenVK build has verbose logging info turned on.
If you want MoltenVK to log like the original Vulkan SDK install, use this command when building MoltenVK:
bash
```
$ make macos MVK_CONFIG_LOG_LEVEL=1
```
From a command line terminal, execute the following command:
bash
```
$ sudo make install
```

This will copy your latest macOS build of MoltenVK into /usr/local/lib/libMoltenVK.dylib,
overwriting the file installed by the Vulkan SDK install process.

Running MoltenVK Demo Applications

Once you have compiled and built the MoltenVK runtime distribution package from this MoltenVK repository,
as described in the Building MoltenVK section, you can explore how MoltenVK provides Vulkan
support on macOS, iOS, and tvOS by investigating and running the demo application that is included in MoltenVK.

The MoltenVK Cube demo app is located in the Demos folder. The demo app is available as an Xcode project.
To review and run the included demo app, open the Demos/Demos.xcworkspace workspace in Xcode.

Please read the Demos/README.md document for a description and instructions for running the
included Cube demo app, and for external links to more sophisticated demo applications that can be run on MoltenVK.

Using MoltenVK in Your Application

Once you have compiled and built the MoltenVK runtime distribution package from this MoltenVK repository,
as described in the Building MoltenVK section, follow the instructions in the Installation
section of the Docs/MoltenVK_Runtime_UserGuide.md document
in the Docs directory, to link the MoltenVK libraries and frameworks to your application.

The runtime distribution package in the Package/Latest directory is a stand-alone package, and you can copy
the contents of that directory out of this MoltenVK repository into your own application building environment.

MoltenVK and Vulkan Compliance

MoltenVK is designed to be an implementation of a Vulkan 1.4 subset that runs on macOS, iOS,
tvOS, and visionOS platforms by mapping Vulkan capability to native Metal capability.

The fundamental design and development goal of MoltenVK is to provide this capability in a way that
is both maximally compliant with the Vulkan 1.4 specification, and maximally performant.

Such compliance and performance is inherently affected by the capability available through Metal,
as the native graphics driver on macOS, iOS, tvOS, and visionOS platforms. Vulkan
compliance may fall into one of the following categories:

Direct mapping between Vulkan capabilities and Metal capabilities. Within MoltenVK, the vast
majority of Vulkan capability is the result of this type of direct mapping.
Synthesized compliance through alternate implementation. A small amount of capability is provided using
this mechanism, such as via an extra render or compute shader stage.
Non-compliance. This appears where the capabilities of Vulkan and Metal are sufficiently different, that
there is no practical, or reasonably performant, mechanism to implement a Vulkan capability in Metal.
Because of design differences between Vulkan and Metal, a very small amount of capability falls into this
category, and at present MoltenVK is not fully compliant with the Vulkan specification. A list of
known limitations is documented in the MoltenVK_Runtime_UserGuide.md
document in the Docs directory.

The MoltenVK development team welcomes you to post Issues
of non-compliance, and engage in discussions about how compliance can be improved, and non-compliant features can
be implemented or worked around.

MoltenVK is a key component of the
Khronos Vulkan Portability Initiative,
whose intention is to provide specifications, resources, and tools to allow developers to understand and design
their Vulkan apps for maximum cross-platform compatibility and portability, including on platforms, such as
macOS, iOS, tvOS, and visionOS, where a native Vulkan driver is not available.

Getting Support

If you have a question about using MoltenVK, you can ask it in
MoltenVK Discussions.
This forum is monitored by MoltenVK contributors and users.
If you encounter an issue with the behavior of MoltenVK, or want to request an enhancement,
you can report it in the MoltenVK Issues List.
If you encounter an issue with the Vulkan SDK, including the Validation Layers, you can report it in the
Vulkan SDK Issues List.
If you explore MoltenVK and determine that it does not meet your requirements at this time, we would appreciate
hearing why that is so, in MoltenVK Discussions.
The goal of MoltenVK is to increase the value of Vulkan as a true cross-platform ecosystem, by providing
Vulkan on Apple platforms. Hearing why this is currently not working for you will help us in that goal.

Contributing to MoltenVK Development

As a public open-source project, MoltenVK benefits from code contributions from a wide range of developers,
and we encourage you to get involved and contribute code to this MoltenVK repository.

To contribute your code, submit a Pull Request
to this repository. The first time you do this, you will be asked to agree to the MoltenVK
Contributor License Agreement.

Licensing

MoltenVK is licensed under the Apache 2.0 license. All new source code files should include a
copyright header at the top, containing your authorship copyright and the Apache 2.0 licensing stub.
You may copy the text from an existing source code file as a template.

The Apache 2.0 license guarantees that code in the MoltenVK repository is free of Intellectual Property
encumbrances. In submitting code to this repository, you are agreeing that the code is free of any Intellectual
Property claims.

Vulkan Validation

Despite running on top of Metal, MoltenVK operates as a Vulkan core layer. As such, as per the
error handling guidelines of the Vulkan specification, MoltenVK should not perform Vulkan validation. When adding functionality
to MoltenVK, avoid adding unnecessary validation code.

Validation and error generation is appropriate within MoltenVK in cases where MoltenVK deviates
from behavior defined by the Vulkan specification. This most commonly occurs when required behavior cannot
be mapped to functionality available within Metal. In that situation, it is important to provide feedback to
the application developer to that effect, by performing the necessary validation, and reporting an error.

Currently, there is some excess Vulkan validation and error reporting code within MoltenVK, added before
this guideline was introduced. You are encouraged to remove such code if you encounter it while performing other
MoltenVK development. Do not remove validation and error reporting code that is covering a deviation in
behavior from the Vulkan specification.

Memory Management

Metal, and other Objective-C objects in Apple's SDK frameworks, use reference counting for memory management.
As a contributor to MoltenVK, when instantiating Objective-C objects, it is important that you do not rely on
the app providing autorelease pools to do memory management for you. Because many Vulkan games and apps may be
ported from other platforms, they will often not automatically include autorelease pools in their threading models.

As a contributor to MoltenVK, avoid the use of the Metal autorelease method, or any object Metal creation
methods that imply internal use of autorelease, (eg- [NSString stringWithFormat: ], etc). Instead, favor object
creation methods that return a retained object (eg- [[NSString alloc] initWithFormat: ], etc), and manually track
and release those objects. If you need to use autoreleased objects, wrap your code in an @autoreleasepool {...} block.

Code Formatting

When contributing code, please honour the code formatting style found in existing MoltenVK source code.
In future, this will formally be enforced using clang-format.

File: Demos/README.md

#MoltenVK Demo Projects

Cube
Khronos Vulkan-Samples

Cube

The basic canonical Cube sample app from the
Vulkan-Tools repository
is included in this MoltenVK package.

This demo renders a basic textured cube that spins in place.

The demo can be found in the Cube folder, and in the Cube group in the
Xcode Project Navigator in the Demos.xcworkspace Xcode workspace.

To run this demo, run the Cube-macOS, Cube-iOS, or Cube-tvOS Scheme from within Xcode.
In addition to devices, this demo will also run on an iOS Simulator destination.
This demo is not supported on a tvOS Simulator destination.

The Cube demo is a simple example of installing MoltenVK as a libMoltenVK.dylib library that
is dynamically linked to the application, and the Vulkan calls all use Volk to dynamically access
function pointers, retrieved from MoltenVK using vkGetInstanceProcAddr() and vkGetDeviceProcAddr().
It supports all platforms, including Mac Catalyst, iOSSimulator and tvOS Simulator.

Khronos Vulkan Samples

Khronos Group provides a repository
containing a full suite of standard Vulkan samples that run on MoltenVK on macOS.

File: Docs/MoltenVK_Configuration_Parameters.md

MoltenVK Configuration Parameters

MoltenVK provides the ability to configure and optimize MoltenVK for your particular
application runtime requirements and development-time needs.

At runtime, configuration can be helpful in situtations where Metal behavior is different
than Vulkan behavior, and the results or performance you receive can depend on how MoltenVK
works around those differences, which, in turn, may depend on how you are using Vulkan.
Different apps might benefit differently in this handling.

Additional configuration parameters can be helpful at development time by providing you with
additional tracing, debugging, and performance measuring capabilities.

Each configuration parameter has a name and value, and can be passed to MoltenVK
via any of the following mechanisms:

The standard Vulkan VK_EXT_layer_settings extension.
Application runtime environment variables.
Build settings at MoltenVK build time.

Parameter values configured by build settings at MoltenVK build time can be overridden
by values set by environment variables, which, in turn, can be overridden during VkInstance
creation via the Vulkan VK_EXT_layer_settings extension.

Using the VK_EXT_layer_settings extension is the preferred mechanism, as it is a standard
Vulkan extension, and is supported by the Vulkan loader and layers. When using the
VK_EXT_layer_settings extension, set VkLayerSettingEXT::pLayerName to the value of
kMVKMoltenVKDriverLayerName found in the mvk_vulkan.h header (or simply to "MoltenVK").

Using environment variables can be a convinient mechanism to modify configuration parameters
during runtime debugging in the field (if the settings are not overridden during VkInstance
creation via the Vulkan VK_EXT_layer_settings extension).

MVK_CONFIG_ACTIVITY_PERFORMANCE_LOGGING_STYLE

Type: Enumeration

0: Log repeatedly every number of frames configured by the MVK_CONFIG_PERFORMANCE_LOGGING_FRAME_COUNT parameter.
1: Log immediately after each performance measurement.
2: Log at the end of the VkDevice lifetime. This is useful for one-shot apps such as testing frameworks.
3: Log at the end of the VkDevice lifetime, but continue to accumulate across mulitiple VkDevices
throughout the app process. This is useful for testing frameworks that create many VkDevices serially.

Default: `0`

If the MVK_CONFIG_PERFORMANCE_TRACKING parameter is enabled, this parameter controls
when MoltenVK should log activity performance events.

MVK_CONFIG_ADVERTISE_EXTENSIONS

Type: UInt32

Default: `1`

Controls which extensions MoltenVK should advertise it supports in vkEnumerateInstanceExtensionProperties()
and vkEnumerateDeviceExtensionProperties(). This can be useful when testing MoltenVK against specific
limited functionality. The value of this parameter is a Bitwise-OR of the following values:

1: All supported extensions.
2: WSI extensions supported on the platform.
4: Vulkan Portability Subset extensions.

Any prerequisite extensions are also advertised. If bit 1 is included, all supported
extensions will be advertised. A value of zero means no extensions will be advertised.

MVK_CONFIG_API_VERSION_TO_ADVERTISE

Type: UInt32

Default: `4210688` (decimal number for `VK_API_VERSION_1_4`)

Controls the Vulkan API version that MoltenVK should advertise in vkEnumerateInstanceVersion(),
after MoltenVK adds the VK_HEADER_VERSION component.

Set this value to one of:

4210688 (decimal number for VK_API_VERSION_1_4)
4206592 (decimal number for VK_API_VERSION_1_3)
4202496 (decimal number for VK_API_VERSION_1_2)
4198400 (decimal number for VK_API_VERSION_1_1)
4194304 (decimal number for VK_API_VERSION_1_0)

or one of the shorthand versions:

14 (VK_API_VERSION_1_4)
13 (VK_API_VERSION_1_3)
12 (VK_API_VERSION_1_2)
11 (VK_API_VERSION_1_1)
10 (VK_API_VERSION_1_0)

The shorthand versions are a user convenience, and MoltenVK will
convert the shorthand value to the actual Vulkan version value upon setting.

MVK_CONFIG_AUTO_GPU_CAPTURE_OUTPUT_FILE

Type: String

Default: `""`

(The default value is an empty string).

If MVK_CONFIG_AUTO_GPU_CAPTURE_SCOPE is any value other than 0, this is the path to a
file where the automatic GPU capture will be saved. If this parameter is an empty string
(the default), automatic GPU capture will be handled by the Xcode user interface.

If this parameter is set to a valid file path, the Xcode scheme need not have Metal GPU capture
enabled, and in fact the app need not be run under Xcode's control at all. This is useful in case
the app cannot be run under Xcode's control. A path starting with '~' can be used to place it in
a user's home directory.

MVK_CONFIG_AUTO_GPU_CAPTURE_SCOPE

Type: Enumeration

0: No automatic GPU capture.
1: Automatically capture all GPU activity during the lifetime of a VkDevice.
2: Automatically capture all GPU activity during the rendering and presentation of the first frame.
3: Automatically capture all GPU activity while signaled on a temporary named pipe. Automatically
begins recording whenever the pipe is not empty, and records as many frames as the pipe contains bytes.

Default: `0`

Controls whether Metal should run an automatic GPU capture without the user having to
trigger it manually via the Xcode user interface, and controls the scope under which
that GPU capture will occur. This is useful when trying to capture a one-shot GPU trace,
such as when running a Vulkan CTS test case, or for triggering the capture via an
IPC on a temporary named pipe.

For values 2 and 3, the queue for which the frames are captured is identifed by
the values of the MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_FAMILY_INDEX and
MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_INDEX configuration parameters.

For the automatic GPU capture to occur, the environment variable MTL_CAPTURE_ENABLED must be enabled,
or, if running the app from Xcode, the GPU Frame Capture option can be set to Metal.

To manually trigger a GPU capture via the Xcode user interface, leave this parameter at 0.

MVK_CONFIG_DEBUG

Type: Boolean

Default: `0`

(The default value is 1 if MoltenVK was built in Debug mode).

If enabled, debugging capabilities will be enabled, including logging shader code during runtime shader conversion.

MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_FAMILY_INDEX

Type: UInt32

Default: `0`

The index of the queue family whose presentation submissions will be
used as the default GPU Capture Scope, when GPU Capture is active.

MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_INDEX

Type: UInt32

Default: `0`

The index of the queue, within the queue family identified by the
MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_FAMILY_INDEX parameter, whose presentation
submissions will be used as the default GPU Capture Scope, when GPU Capture is active.

MVK_CONFIG_DISPLAY_WATERMARK

Type: Boolean

Default: `0`

If enabled, a MoltenVK logo watermark will be rendered on top of the scene.
This can be enabled for publicity during demos.

MVK_CONFIG_FAST_MATH_ENABLED

Type: Enumeration

0: Metal shaders will never be compiled with the fast math option.
1: Metal shaders will always be compiled with the fast math option.
2: Metal shaders will be compiled with the fast math option. However, each shader can
limit the types of fast-math used, through the VK_KHR_shader_float_controls2 extension,
or by enabling execution capabilities, such as SignedZeroInfNanPreserve or ContractionOff.

Default: `2`

Identifies when Metal shaders will be compiled with the Metal fast math option enabled.

Shaders compiled with the Metal fast math option enabled perform floating point math significantly
faster, but may optimize floating point operations in ways that violate the IEEE 754 standard.

Enabling Metal fast math can dramatically improve shader performance, and has little practical
effect on the numerical accuracy of most shaders. As such, disabling fast math should be done
carefully and deliberately. For most applications, always enabling fast math is the preferred choice.

Apps that have specific accuracy and handling needs for particular shaders, may elect to set
the value of this property to 2, which compiles shaders with fast math, but allows each shader
to limit the types of fast-math used, as described in the value description above.

MVK_CONFIG_FORCE_LOW_POWER_GPU

Type: Boolean

Default: `0`

Forces MoltenVK to only advertise the low-power GPUs, if availble on the device.

MVK_CONFIG_LOG_LEVEL

Type: Enumeration

0: No logging.
1: Log errors only.
2: Log errors and warning messages.
3: Log errors, warnings and informational messages.
4: Log errors, warnings, infos and debug messages.

Default: `3`

Controls the level of logging performed by MoltenVK.

MVK_CONFIG_MAX_ACTIVE_METAL_COMMAND_BUFFERS_PER_QUEUE

Type: UInt32

Default: `64`

The maximum number of Metal command buffers that can be concurrently active per Vulkan queue. The number
of active Metal command buffers required depends on the MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS parameter.
If MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS is set to anything other than 0, one Metal command buffer
is required per Vulkan command buffer, otherwise one Metal command buffer is required per command buffer
queue submission, which will typically be significantly less than the number of Vulkan command buffers.

MVK_CONFIG_METAL_COMPILE_TIMEOUT

Type: UInt64

Default: `INT64_MAX`

The maximum amount of time, in nanoseconds, to wait for a Metal library, function, or
pipeline state object to be compiled and created by the Metal compiler. An internal error
within the Metal compiler may stall the thread for up to 30 seconds. Setting this value
limits that delay to a specified amount of time, allowing shader compilations to fail fast.

MVK_CONFIG_PERFORMANCE_LOGGING_FRAME_COUNT

Type: UInt32

Default: `0`

If the MVK_CONFIG_PERFORMANCE_TRACKING parameter is enabled, and this parameter is non-zero,
performance and frame-based statistics will be logged, on a repeating cycle, once per this many frames.
If this parameter is zero, or the MVK_CONFIG_PERFORMANCE_TRACKING parameter is disabled,
no frame-based performance statistics will be logged.

MVK_CONFIG_PERFORMANCE_TRACKING

Type: Boolean

Default: `0`

If enabled, performance statistics, as defined by the MVKPerformanceStatistics structure,
are collected, and can be retrieved via the private-API vkGetPerformanceStatisticsMVK() function.

You can also use the MVK_CONFIG_ACTIVITY_PERFORMANCE_LOGGING_STYLE and
MVK_CONFIG_PERFORMANCE_LOGGING_FRAME_COUNT parameters to configure when to log the performance statistics collected by this parameter.

MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS

Type: Enumeration

0: During Vulkan command buffer filling, do not prefill a Metal command buffer for each Vulkan
command buffer. A single Metal command buffer will be created and encoded for all the Vulkan command
buffers included when vkQueueSubmit() is called. MoltenVK automatically creates and drains
a single Metal object autorelease pool when vkQueueSubmit() is called. This is the fastest option,
but potentially has the largest memory footprint.
1: During Vulkan command buffer filling, encode to the Metal command buffer when vkEndCommandBuffer()
is called. MoltenVK automatically creates and drains a single Metal object autorelease pool when
vkEndCommandBuffer() is called. This option has the fastest performance, and the largest memory footprint,
of the prefilling options using autorelease pools.
2: During Vulkan command buffer filling, as each
command is submitted to the Vulkan command buffer, immediately encode it to the Metal command buffer,
and do not retain any command content in the Vulkan command buffer. MoltenVK automatically creates
and drains a Metal object autorelease pool for each and every command added to the Vulkan command buffer.
This option has the smallest memory footprint,
and the slowest performance, of the prefilling options using autorelease pools.
3: During Vulkan command buffer filling, as each
command is submitted to the Vulkan command buffer, immediately encode it to the Metal command buffer,
do not retain any command content in the Vulkan command buffer, and assume the app will ensure that each
thread that fills commands into a Vulkan command buffer has a Metal autorelease pool. MoltenVK will
not create and drain any autorelease pools during encoding. This is the fastest prefilling option, and
generally has a small memory footprint, depending on when the app-provided autorelease pool drains.

Default: `0`

For any value other than 0, be aware of the following:

One Metal command buffer is required for each Vulkan command buffer. Depending on the
number of command buffers that you use, you may also need to change the value of the
MVK_CONFIG_MAX_ACTIVE_METAL_COMMAND_BUFFERS_PER_QUEUE parameter.
Prefilling of a Metal command buffer will not occur during the filling of secondary command buffers
(VK_COMMAND_BUFFER_LEVEL_SECONDARY), or for primary command buffers that are intended to be submitted
to multiple queues concurrently (VK_COMMAND_BUFFER_USAGE_SIMULTANEOUS_USE_BIT).
For primary command buffers that are intended to be reused (VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT
is not set), prefilling will only apply to the first submission. Later submissions of the same command buffer
will behave as if this configuration parameter is set to 0.
If you have recorded commands to a Vulkan command buffer, and then choose to reset that command buffer
instead of submitting it, the corresponding prefilled Metal command buffer will still be submitted.
This is because Metal command buffers do not support the concept of being reset after being filled.
Depending on when and how often you do this, it may cause unexpected visual artifacts and unnecessary GPU load.
This configuration is incompatible with updating descriptors after binding. If any of the UpdateAfterBind
feature flags of VkPhysicalDeviceDescriptorIndexingFeatures or VkPhysicalDeviceInlineUniformBlockFeatures
have been enabled, the value of this parameter will be ignored and treated as if it is 0.

MVK_CONFIG_RESUME_LOST_DEVICE

Type: Boolean

Default: `0`

Controls whether MoltenVK should treat a lost VkDevice as resumable, unless the corresponding
VkPhysicalDevice has also been lost. The VK_ERROR_DEVICE_LOST error has a broad definitional range,
and can mean anything from a GPU hiccup on the current command buffer submission, to a physically removed
GPU. In the case where this error does not impact the VkPhysicalDevice, Vulkan requires that the app
destroy and re-create a new VkDevice. However, not all apps (including CTS) respect that requirement,
leading to what might be a transient command submission failure causing an unexpected catastrophic app failure.

If this parameter is enabled, in the case of a VK_ERROR_DEVICE_LOST error that does NOT impact
the VkPhysicalDevice, MoltenVK will log the error, but will not mark the VkDevice as lost,
allowing the VkDevice to continue to be used. If this parameter is disabled, MoltenVK will
mark the VkDevice as lost, and subsequent use of that VkDevice will be reduced or prohibited.

MVK_CONFIG_SHADER_COMPRESSION_ALGORITHM

Type: Enumeration

0: No compression.
1: LZFSE: Apple proprietary. Good balance of high performance and small compression size, particularly for larger data content.
2: ZLib: Open cross-platform format. For smaller data content, has better performance and smaller size than LZFSE.
3: LZ4: Fastest performance. Largest compression size.
4: LZMA: Slowest performance. Smallest compression size, particular with larger content.

Default: `0`

Controls the type of compression to use on the MSL source code that is stored in memory for use in a pipeline cache.
After being converted from SPIR-V, or loaded directly into a VkShaderModule, and then compiled into a MTLLibrary,
the MSL source code is no longer needed for operation, but it is retained so it can be written out as part of a
pipeline cache export. When a large number of shaders are loaded, this can consume significant memory. In such a case,
this parameter can be used to compress the MSL source code that is awaiting export as part of a pipeline cache.

MVK_CONFIG_SHADER_CONVERSION_FLIP_VERTEX_Y

Type: Boolean

Default: `1`

If enabled, MSL vertex shader code created during runtime shader conversion will
flip the Y-axis of each vertex, as the Vulkan Y-axis is the inverse of OpenGL.

An alternate way to reverse the Y-axis is to employ a negative Y-axis value on
the viewport, in which case this parameter can be disabled.

MVK_CONFIG_SHADER_DUMP_DIR

Type: String

Default: `""`

(The default value is an empty string).

If not empty, MoltenVK will dump all SPIR-V shaders, compiled MSL shaders, and pipeline shader lists to the given directory.
The directory will be non-recursively created if it doesn't already exist.

MVK_CONFIG_SHADER_LOG_ESTIMATED_GLSL

Type: Boolean

Default: `0`

If the MVK_CONFIG_DEBUG parameter is enabled, and this parameter is enabled, when
SPIR-V code is converted to MSL, an estimate of the equivalent GLSL shader will be logged.

MVK_CONFIG_SHOULD_MAXIMIZE_CONCURRENT_COMPILATION

Type: Boolean

Default: `0`

Maximize the concurrent executing compilation tasks.

To have effect, this parameter requires macOS 13.3+, and has no effect on iOS or tvOS.

MVK_CONFIG_SPECIALIZED_QUEUE_FAMILIES

Type: Boolean

Default: `0`

Metal does not distinguish functionality between queues, which would normally mean only a single
general-purpose queue family with multiple queues is needed. However, Vulkan associates command
buffers with a queue family, whereas Metal associates command buffers with a specific Metal queue.
In order to allow a Metal command buffer to be prefilled before it is formally submitted to a Vulkan queue,
each Vulkan queue family can support only a single Metal queue. As a result, in order to provide parallel
queue operations, MoltenVK provides multiple queue families, each with a single queue.

If this parameter is disabled, all queue families will be advertised as having general-purpose
graphics + compute + transfer functionality, which is how the actual Metal queues behave.

If this parameter is enabled, one queue family will be advertised as having general-purpose
graphics + compute + transfer functionality, and the remaining queue families will be advertised
as having specialized graphics or compute or transfer functionality, to make it easier for some
apps to select a queue family with the appropriate requirements.

MVK_CONFIG_SWAPCHAIN_MIN_MAG_FILTER_USE_NEAREST

Type: Boolean

Default: `1`

If enabled, swapchain images will use simple Nearest sampling when minifying or magnifying
the swapchain image to fit a physical display surface. If disabled, swapchain images will
use Linear sampling when magnifying the swapchain image to fit a physical display surface.
Enabling this setting avoids smearing effects when swapchain images are simple interger
multiples of display pixels (eg- macOS Retina, and typical of graphics apps and games),
but may cause aliasing effects when using non-integer display scaling.

MVK_CONFIG_SWITCH_SYSTEM_GPU

Type: Boolean

Default: `1`

If enabled, when the app creates a VkDevice from a VkPhysicalDevice (GPU) that is neither
headless nor low-power, and is different than the GPU used by the windowing system, the
windowing system will be forced to switch to use the GPU selected by the Vulkan app.
When the Vulkan app is ended, the windowing system will automatically switch back to
using the previous GPU, depending on the usage requirements of other running apps.

If disabled, the Vulkan app will render using its selected GPU, and if the windowing
system uses a different GPU, the windowing system compositor will automatically copy
framebuffer content from the app GPU to the windowing system GPU.

The value of this parmeter has no effect on systems with a single GPU, or when the
Vulkan app creates a VkDevice from a low-power or headless VkPhysicalDevice (GPU).

Switching the windowing system GPU to match the Vulkan app GPU maximizes app performance,
because it avoids the windowing system compositor from having to copy framebuffer content
between GPUs on each rendered frame. However, doing so forces the entire system to
potentially switch to using a GPU that may consume more power while the app is running.

Some Vulkan apps may want to render using a high-power GPU, but leave it up to the
system window compositor to determine how best to blend content with the windowing
system, and as a result, may want to disable this parameter.

MVK_CONFIG_SYNCHRONOUS_QUEUE_SUBMITS

Type: Boolean

Default: `1`

If enabled, queue command submissions vkQueueSubmit() and vkQueuePresentKHR()
will be processed on the thread that called the submission function. If disabled,
processing will be dispatched to a GCD dispatch_queue whose priority is determined
by VkDeviceQueueCreateInfo::pQueuePriorities during vkCreateDevice().

MVK_CONFIG_TEXTURE_1D_AS_2D

Type: Boolean

Default: `1`

Controls whether MoltenVK should use a Metal 2D texture with a height of 1 for a
Vulkan 1D image, or use a native Metal 1D texture. Metal imposes significant restrictions
on native 1D textures, including not being renderable, clearable, or permitting mipmaps.
Using a Metal 2D texture allows Vulkan 1D textures to support this additional functionality.

MVK_CONFIG_TIMESTAMP_PERIOD_LOWPASS_ALPHA

Type: Float32

Default: `1.0`

This parameter is ignored on Apple Silicon (Apple GPU) devices.

Non-Apple GPUs can have a dynamic timestamp period, which varies over time according to GPU
workload. Depending on how often the app samples the VkPhysicalDeviceLimits::timestampPeriod
value using vkGetPhysicalDeviceProperties(), the app may want up-to-date, but potentially
volatile values, or it may find average values more useful.

The value of this parameter sets the alpha (A) value of a simple lowpass filter on the
timestampPeriod value, of the form:

text

TPout = (1 - A)TPout + (A * TPin)

The alpha value can be set to a float between 0.0 and 1.0. Values of alpha closer to 0.0
cause the value of timestampPeriod to vary slowly over time and be less volatile, and values
of alpha closer to 1.0 cause the value of timestampPeriod to vary quickly and be more volatile.

Apps that query the timestampPeriod value infrequently will prefer low volatility, whereas
apps that query frequently may prefer higher volatility, to track more recent changes.

MVK_CONFIG_TRACE_VULKAN_CALLS

Type: Enumeration

0: No Vulkan call logging.
1: Log the name of each Vulkan call when the call is entered.
2: Log the name and thread ID of each Vulkan call when the call is entered.
3: Log the name of each Vulkan call when the call is entered and exited.
This effectively brackets any other logging activity within the scope of the Vulkan call.
4: Log the name and thread ID of each Vulkan call when the call is entered, and name when exited.
This effectively brackets any other logging activity within the scope of the Vulkan call.
5: Same as 3, plus logs the time spent inside the Vulkan function.
6: Same as 4, plus logs the time spent inside the Vulkan function.

Default: `0`

Controls the information MoltenVK logs for each Vulkan call made by the application.

MVK_CONFIG_USE_COMMAND_POOLING

Type: Boolean

Default: `1`

Controls whether MoltenVK should use pools to manage memory used when adding commands to command buffers.
If this setting is enabled, MoltenVK will use a pool to hold command resources for reuse during command execution.
If this setting is disabled, command memory is allocated and destroyed each time a command is executed.
This is a classic time-space trade off. When command pooling is active, the memory in the pool can be
cleared via a call to the vkTrimCommandPoolKHR() command.

MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS

Type: Boolean

Default: `1`

Controls whether MoltenVK should use Metal argument buffers for resources defined in descriptor sets,
if Metal argument buffers are supported on the platform. Using Metal argument buffers dramatically
increases the number of buffers, textures and samplers that can be bound to a pipeline shader, and in most
cases improves performance.

MVK_CONFIG_USE_METAL_PRIVATE_API

Type: Boolean

Default: Value of `MVK_USE_METAL_PRIVATE_API`

If enabled, MoltenVK will use private interfaces exposed by Metal to implement Vulkan
features that are difficult to support otherwise.

Unlike MVK_USE_METAL_PRIVATE_API, this setting may be overridden at run time.

This option is not available unless MoltenVK was built with MVK_USE_METAL_PRIVATE_API set to 1.

MVK_CONFIG_USE_MTLHEAP

Type: Enumeration

0: Do not use MTLHeap for allocating resources.
1: Use MTLHeap for allocating resources, where safe to do so. On AMD GPUs, this is the same as 0,
due to potential challenges with MTLHeap usage on those platforms. On other GPUs this is the same as 2.
2: Use MTLHeap for allocating resources.

Default: `1`

Controls whether MoltenVK should use MTLHeap for allocating textures and buffers from device memory.
If this setting is active, MoltenVK will allocate a placement MTLHeap for each VkDeviceMemory instance,
and allocate textures and buffers from that placement heap. If this parameter is not active, MoltenVK will
allocate textures and buffers from general device memory.

Vulkan extension VK_EXT_image_2d_view_of_3d requires this parameter to be active,
to allow aliasing of texture memory between the 3D image and the 2D view.

VK_IMAGE_CREATE_BLOCK_TEXEL_VIEW_COMPATIBLE_BIT also requires this parameter to be active,
to allow aliasing of texture memory between the compressed image and the uncompressed view.
Note that this is only compatible with Apple GPUs.

To force MTLHeap to be used on AMD GPUs, set this parameter to 2.
To disable the use of MTLHeap on any GPU, set this parameter to 0.

MVK_CONFIG_VK_SEMAPHORE_SUPPORT_STYLE

Type: Enumeration

0: Limit Vulkan to a single queue, with no explicit semaphore synchronization, and use Metal's implicit
guarantees that all operations submitted to a queue will give the same result as if they had been run in submission order.
1: Use Metal events (MTLEvent) when available on the platform, and where safe. This will revert to the same as 0 on some
NVIDIA GPUs and Rosetta2, due to potential challenges with MTLEvents on those platforms, or in older environments where
MTLEvents are not supported.
2: Always use Metal events (MTLEvent) when available on the platform. This will revert to the same as 0 in older
environments where MTLEvents are not supported.
3: Use CPU callbacks upon GPU submission completion. This is the slowest technique, but allows multiple queues, compared to 0.

Default: `1`

Determines the style used to implement Vulkan semaphore (VkSemaphore) functionality in Metal.

In the special case of VK_SEMAPHORE_TYPE_TIMELINE semaphores, MoltenVK will always use
MTLSharedEvent, regardless of the value of this parameter.

MVK_CONFIG_LIVE_CHECK_ALL_RESOURCES

Type: Boolean

Default: `0`

Makes MoltenVK treat all descriptors as if they had VK_DESCRIPTOR_BINDING_PARTIALLY_BOUND_BIT set.
Versions of MoltenVK with this flag are less forgiving of applications that bind descriptors that point to
destroyed objects, so this option can be used to temporarily work around any breakage that may have caused.

File: Docs/MoltenVK_Runtime_UserGuide.md

MoltenVK Runtime User Guide

About This Document
About MoltenVK
Installing MoltenVK in Your Vulkan Application
Interacting with the MoltenVK Runtime
- MoltenVK Header Files
- Configuring MoltenVK
Debugging Your MoltenVK Application using Metal Frame Capture
Metal Shading Language Shaders
- Troubleshooting Shader Conversion
Performance Considerations
Known MoltenVK Limitations

About This Document

This document describes how to integrate the MoltenVK runtime distribution package into a game or
application, once MoltenVK has been built into a framework or library for macOS, iOS, or tvOS.

To learn how to use the MoltenVK open-source repository to build a MoltenVK runtime
distribution package, see the main README.md document in the MoltenVK repository.

About MoltenVK

MoltenVK is a layered implementation of Vulkan 1.4
graphics and compute functionality, that is built on Apple's Metal
graphics and compute framework on macOS, iOS, and tvOS. MoltenVK allows you to use Vulkan
graphics and compute functionality to develop modern, cross-platform, high-performance graphical games
and applications, and to run them across many platforms, including macOS, iOS, tvOS, Simulators,
and Mac Catalyst.

To provide Vulkan capability to the macOS, iOS, and tvOS platforms, MoltenVK uses
Apple's publicly available API's, including Metal. MoltenVK does not use any
private or undocumented API calls or features unless configured to do so at build time, so your
app will be compatible with all standard distribution channels, including Apple's App Store.

Installing MoltenVK in Your Vulkan Application

Installation of MoltenVK in your application is straightforward and easy!

Depending on your build and deployment needs, you can link MoltenVK to your application either
as either a static or dynamic universal XCFramework, or on macOS, as a dynamic library (.dylib).

Install MoltenVK as a Universal `XCFramework`

Note: Xcode 14 introduced a new static linkage model that is not compatible with previous
versions of Xcode. If you link to a MoltenVK.xcframework that was built with Xcode 14 or later,
also use Xcode 14 or later to link it to your app or game.

If you need to use Xcode 13 or earlier to link MoltenVK.xcframework to your app or game,
first build MoltenVK with Xcode 13 or earlier.

Or, if you want to use Xcode 14 or later to build MoltenVK, in order to be able
to use the latest Metal capabilities, but need to use Xcode 13 or earlier to link MoltenVK.xcframework
to your app or game, first add the value -fno-objc-msgsend-selector-stubs to the OTHER_CFLAGS Xcode build
setting in the MoltenVK.xcodeproj and MoltenVKShaderConverter.xcodeproj Xcode projects, build
MoltenVK with Xcode 14 or later, and then link MoltenVK.xcframeworkto your app or game using Xcode 13 or earlier.

To link MoltenVK to your application as either a static or dynamic XCFramework, follow these steps:

Open your application in Xcode and select your application's target in the Project Navigator panel.
Open the Build Settings tab.
1. In the Header Search Paths (aka HEADER_SEARCH_PATHS) setting,
  add an entry that points to the MoltenVK/include folder.
2. (Note: This step is not required if linking to the static XCFramework) If linking to the dynamic XCFramework,
  in the Runpath Search Paths (aka LD_RUNPATH_SEARCH_PATHS) setting, add entries that match where the
  framework will be located in your runtime environment. If the dynamic library is to be embedded within your
  application, you would typically add one or both of the following entries for a macOS platform target:
  text
```
@executable_path/../Frameworks
@executable_path/../Frameworks/MoltenVK.framework
```
  or for a platform target other than macOS add one or both of the following entries:
  text
```
@executable_path/Frameworks
@executable_path/Frameworks/MoltenVK.framework
```
  MoltenVK.framework is internally configured to be located at @rpath/MoltenVK.framework/MoltenVK.
Open the General tab and drag either Package/Latest/MoltenVK/static/MoltenVK.xcframework or
Package/Latest/MoltenVK/dynamic/MoltenVK.xcframework to the Embed Frameworks (sometimes labeled
Frameworks, Libraries, and Embedded Content) list, and ensure the Embed & Sign options is selected.

Install MoltenVK as a Dynamic Library on _macOS_

To link MoltenVK to your macOS application as a dynamic library (.dylib), follow these steps:

Open your application in Xcode and select your application's target in the
Project Navigator panel.
Open the Build Settings tab.
1. In the Header Search Paths (aka HEADER_SEARCH_PATHS) setting,
  add an entry that points to the MoltenVK/include folder.
2. In the Runpath Search Paths (aka LD_RUNPATH_SEARCH_PATHS) setting,
  add an entry that matches where the dynamic library will be located in your runtime
  environment. If the dynamic library is to be embedded within your application,
  you would typically set this to @executable_path/../Frameworks.
  
  The libMoltenVK.dylib library in MoltenVK.framework is internally configured
  to be located at @rpath/libMoltenVK.dylib.
Open the General tab and drag Package/Latest/MoltenVK/dynamic/dylib/macOS/libMoltenVK.dylib
to the Embed Frameworks (sometimes labeled Frameworks, Libraries, and Embedded Content) list,
and ensure the Embed & Sign options is selected.

Optionally Link to Required System Libraries

Open the Build Phases tab and open the Link Binary With Libraries list.

If your application does not use use C++, click the + button,
and add libc++.tbd by selecting it from the list of system frameworks.
This is needed because MoltenVK uses C++ system libraries internally.
If you do not have the Link Frameworks Automatically (aka CLANG_MODULES_AUTOLINK) and
Enable Modules (C and Objective-C) (aka CLANG_ENABLE_MODULES) settings enabled, click the
+ button, and add the following items by selecting them from the list of system frameworks:
- Metal.framework
- Foundation.framework.
- QuartzCore.framework
- CoreGraphics.framework
- IOSurface.framework
- IOKit.framework (macOS)
- AppKit.framework (macOS)
- UIKit.framework (iOS or tvOS)

Build and Runtime Requirements

MoltenVK references the latest Apple SDK frameworks. To access these frameworks when building
your app, and to avoid build errors, be sure to use the latest publicly available version of Xcode.

Once built, your app integrating the MoltenVK libraries can be run on macOS, iOS or tvOS
devices that support Metal, or on the Xcode iOS Simulator or tvOS Simulator.

At runtime, MoltenVK requires at least macOS 12.0, iOS 15, or tvOS 15.
- This support policy is based on the earliest deployment target officially supported
  by the latest version of Xcode.
Information on macOS devices that are compatible with Metal can be found in
this article.
Information on iOS devices that are compatible with Metal can be found in
this article.

When a Metal app is running from Xcode, the default Scheme settings may reduce performance.
To improve performance and gain the benefits of Metal, perform the following in Xcode:

Open the Scheme Editor for building your main application. You can do
this by selecting Edit Scheme... from the Scheme drop-down menu, or select
Product -> Scheme -> Edit Scheme... from the main menu.
On the Info tab, set the Build Configuration to Release, and disable the
Debug executable check-box.
On the Options tab, disable both the Metal API Validation and GPU Frame Capture
options. For optimal performance, you may also consider disabling the other simulation
and debugging options on this tab. For further information, see the
Xcode Scheme Settings and Performance
section of Apple's Metal Programming Guide documentation.

Interacting with the MoltenVK Runtime

You programmatically configure and interact with the MoltenVK runtime through function
calls, enumeration values, and capabilities, in exactly the same way you do with other
Vulkan implementations. MoltenVK contains several header files that define access
to Vulkan and MoltenVK function calls.

In your application code, you access Vulkan features through the API defined in the standard
vulkan.h header file. This file is included in the MoltenVK framework, and can be included
in your source code files as follows:

text

#include <vulkan/vulkan.h>

In addition to core Vulkan functionality, MoltenVK also supports the following Vulkan extensions:

VK_KHR_16bit_storage
VK_KHR_8bit_storage
VK_KHR_bind_memory2
VK_KHR_buffer_device_address
- Requires GPU Tier 2 argument buffers support.
VK_KHR_calibrated_timestamp
- Requires Metal 2.2.
VK_KHR_copy_commands2
VK_KHR_create_renderpass2
VK_KHR_dedicated_allocation
VK_KHR_deferred_host_operations
VK_KHR_depth_stencil_resolve
VK_KHR_descriptor_update_template
VK_KHR_device_group
VK_KHR_device_group_creation
VK_KHR_draw_indirect_count
VK_KHR_driver_properties
VK_KHR_dynamic_rendering
VK_KHR_dynamic_rendering_local_read
VK_KHR_external_fence
VK_KHR_external_fence_capabilities
VK_KHR_external_memory
VK_KHR_external_memory_capabilities
VK_KHR_external_semaphore
VK_KHR_external_semaphore_capabilities
VK_KHR_format_feature_flags2
VK_KHR_fragment_shader_barycentric
- Requires Metal 2.2 on Mac or Metal 2.3 on iOS.
VK_KHR_get_memory_requirements2
VK_KHR_get_physical_device_properties2
VK_KHR_get_surface_capabilities2
VK_KHR_global_priority
VK_KHR_image_format_list
VK_KHR_imageless_framebuffer
VK_KHR_incremental_present
VK_KHR_index_type_uint8
VK_KHR_line_rasterization
VK_KHR_load_store_op_none
VK_KHR_maintenance1
VK_KHR_maintenance2
VK_KHR_maintenance3
VK_KHR_maintenance4
VK_KHR_maintenance5
VK_KHR_maintenance6
VK_KHR_maintenance7
VK_KHR_maintenance8
VK_KHR_maintenance9
VK_KHR_map_memory2
VK_KHR_multiview
VK_KHR_portability_subset
VK_KHR_present_id
VK_KHR_present_id2
VK_KHR_present_wait
VK_KHR_present_wait2
VK_KHR_push_descriptor
VK_KHR_relaxed_block_layout
VK_KHR_robustness2
VK_KHR_sampler_mirror_clamp_to_edge
- Requires a Mac GPU or Apple family 7 GPU.
VK_KHR_sampler_ycbcr_conversion
VK_KHR_separate_depth_stencil_layouts
VK_KHR_shader_atomic_int64
VK_KHR_shader_draw_parameters
VK_KHR_shader_expect_assume
VK_KHR_shader_float_controls
VK_KHR_shader_float_controls2
VK_KHR_shader_float16_int8
VK_KHR_shader_fma
VK_KHR_shader_integer_dot_product
VK_KHR_shader_maximal_reconvergence
VK_KHR_shader_non_semantic_info
VK_KHR_shader_quad_control
VK_KHR_shader_relaxed_extended_instruction
VK_KHR_shader_subgroup_extended_types
- Requires Metal 2.1 on Mac or Metal 2.2 and Apple family 4 on iOS.
VK_KHR_shader_subgroup_rotate
- Requires Metal 2.1 on Mac or Metal 2.2 and Apple family 4 on iOS.
VK_KHR_shader_subgroup_uniform_control_flow
VK_KHR_shader_terminate_invocation
VK_KHR_spirv_1_4
VK_KHR_storage_buffer_storage_class
VK_KHR_surface
VK_KHR_surface_maintenance1
VK_KHR_surface_protected_capabilities
VK_KHR_swapchain
VK_KHR_swapchain_maintenance1
VK_KHR_swapchain_mutable_format
VK_KHR_synchronization2
VK_KHR_timeline_semaphore
VK_KHR_uniform_buffer_standard_layout
VK_KHR_variable_pointers
VK_KHR_vertex_attribute_divisor
VK_KHR_vulkan_memory_model
VK_KHR_zero_initialize_workgroup_memory
VK_EXT_4444_formats
- Requires 16-bit formats and either native texture swizzling or manual swizzling to be enabled.
VK_EXT_buffer_device_address
- Requires GPU Tier 2 argument buffers support.
VK_EXT_calibrated_timestamps
- Requires Metal 2.2.
VK_EXT_debug_marker
VK_EXT_debug_report
VK_EXT_debug_utils
VK_EXT_depth_clip_control
VK_EXT_descriptor_indexing
- Initial release limited to Metal Tier 1: 96/128 textures,
  16 samplers, except macOS 11.0 (Big Sur) or later, or on older versions of macOS using
  an Intel GPU, and if Metal argument buffers enabled in config.
VK_EXT_extended_dynamic_state
- Requires Metal 3.1 for VK_DYNAMIC_STATE_VERTEX_INPUT_BINDING_STRIDE.
VK_EXT_extended_dynamic_state2
- Primitive restart is always enabled, as Metal does not support disabling it (VK_DYNAMIC_STATE_PRIMITIVE_RESTART_ENABLE_EXT).
VK_EXT_extended_dynamic_state3
- Metal does not support VK_POLYGON_MODE_POINT
VK_EXT_external_memory_host
VK_EXT_external_memory_metal
VK_EXT_fragment_shader_interlock
- Requires Metal 2.0 and Raster Order Groups.
VK_EXT_global_priority
VK_EXT_global_priority_query
VK_EXT_hdr_metadata
- macOS only.
VK_EXT_headless_surface
VK_EXT_host_image_copy
VK_EXT_host_query_reset
VK_EXT_image_2d_view_of_3d
- Requires MVK_CONFIG_USE_MTLHEAP to be active.
VK_EXT_image_robustness
VK_EXT_index_type_uint8
VK_EXT_inline_uniform_block
VK_EXT_layer_settings
VK_EXT_legacy_dithering
- Requires a build of MoltenVK with MVK_USE_METAL_PRIVATE_API enabled.
VK_EXT_line_rasterization
VK_EXT_load_store_op_none
VK_EXT_memory_budget
- Requires Metal 2.0.
VK_EXT_metal_objects
VK_EXT_metal_surface
VK_EXT_multi_draw
VK_EXT_nested_command_buffer
VK_EXT_non_seamless_cube_map
- Requires a build of MoltenVK with MVK_USE_METAL_PRIVATE_API enabled.
VK_EXT_pipeline_creation_cache_control
VK_EXT_pipeline_creation_feedback
VK_EXT_pipeline_robustness
VK_EXT_post_depth_coverage
- iOS and macOS, requires family 4 (A11) or better Apple GPU.
VK_EXT_primitive_topology_list_restart
- Requires a build of MoltenVK with MVK_USE_METAL_PRIVATE_API enabled.
VK_EXT_private_data
VK_EXT_provoking_vertex
- Requires a build of MoltenVK with MVK_USE_METAL_PRIVATE_API enabled.
VK_EXT_robustness2
VK_EXT_sample_locations
VK_EXT_sampler_filter_minmax
- Requires Apple GPU family 10 and macOS 26 or iOS 26.
VK_EXT_scalar_block_layout
VK_EXT_separate_stencil_usage
VK_EXT_shader_atomic_float
- Requires Metal 3.0.
VK_EXT_shader_demote_to_helper_invocation
- Requires Metal Shading Language 2.3.
VK_EXT_shader_stencil_export
- Requires Mac GPU family 2 or iOS GPU family 5.
VK_EXT_shader_subgroup_ballot
- Requires Mac GPU family 2 or Apple GPU family 4.
VK_EXT_shader_subgroup_vote
- Requires Mac GPU family 2 or Apple GPU family 4.
VK_EXT_shader_viewport_index_layer
VK_EXT_subgroup_size_control
- Requires Metal 2.1 on Mac or Metal 2.2 and Apple family 4 on iOS.
VK_EXT_surface_maintenance1
VK_EXT_swapchain_colorspace
VK_EXT_swapchain_maintenance1
VK_EXT_texel_buffer_alignment
- Requires Metal 2.0.
VK_EXT_texture_compression_astc_hdr
- iOS and macOS, requires family 6 (A13) or better Apple GPU.
VK_EXT_tooling_info
VK_EXT_vertex_attribute_divisor
VK_EXT_ycbcr_2plane_444_formats
VK_AMD_gpu_shader_half_float
VK_AMD_negative_viewport_height
VK_AMD_shader_image_load_store_lod
- Requires Apple GPU.
VK_AMD_shader_trinary_minmax
- Requires Metal 2.1.
VK_GOOGLE_display_timing
VK_IMG_format_pvrtc
- Requires Apple GPU.
VK_INTEL_shader_integer_functions2
VK_MVK_ios_surface
- Obsolete. Use VK_EXT_metal_surface instead.
VK_MVK_macos_surface
- Obsolete. Use VK_EXT_metal_surface instead.
VK_NV_fragment_shader_barycentric
- Requires Metal 2.2 on Mac or Metal 2.3 on iOS.

In order to visibly display your content on macOS, iOS, or tvOS, you must enable the
VK_EXT_metal_surface extension, and use the function defined in that extension to create a
Vulkan rendering surface. You can enable the VK_EXT_metal_surface extension by defining
the VK_USE_PLATFORM_METAL_EXT guard macro in your compiler build settings. See the description
of the mvk_vulkan.h file below for a convenient way to enable this extension automatically.

When creating a CAMetalLayer to underpin the Vulkan surface to render to, it is strongly
recommended that you ensure the delegate of the CAMetalLayer is the NSView/UIView in
which the layer is contained, to ensure correct and optimized Vulkan swapchain and refresh
timing behavior across multiple display screens that might have different properties.

The view will automatically be the delegate of the layer when the view creates the
CAMetalLayer, as per Apple's documentation:

If the layer object was created by a view, the view typically assigns itself as the layer’s
delegate automatically, and you should not change that relationship. For layers you create
yourself, you can assign a delegate object and use that object to provide the contents of
the layer dynamically and perform other tasks.

But in the case where you create the CAMetalLayer yourself and assign it to the view,
you should also assign the view as the delegate of the layer.

MoltenVK Header Files

MoltenVK provides additional functionality beyond standard Vulkan functionality,
to support configuration options and query behaviour that is specific to the MoltenVK
implementation of Vulkan functionality.

The following API header files are included in the MoltenVK package, each of which
can be included in your application source code as follows:

text

#include <MoltenVK/HEADER_FILE>

where HEADER_FILE is one of the following:

mvk_vulkan.h - This is a convenience header file that loads the <vulkan/vulkan.h> header file
with platform settings to enable the appropriate Vulkan WSI surface and portability extensions.
mvk_private_api.h - Contains private structures and functions to query MoltenVK about
MoltenVK version and configuration, runtime performance information, and available
Metal capabilities.

NOTE: THE FUNCTIONS in mvk_private_api.h ARE NOT SUPPORTED BY THE Vulkan Loader
and Layers, AND CAN ONLY BE USED WHEN MoltenVK IS LINKED DIRECTLY TO YOUR APPLICATION.
mvk_datatypes.h - Contains helpful functions for converting between Vulkan and Metal
data types. You do not need to use this functionality to use MoltenVK, as MoltenVK
converts between Vulkan and Metal datatypes automatically (using the functions declared
in this header). These functions are exposed in this header as a convienience for your own
purposes such as interacting with Metal directly, or simply logging data values.

Configuring MoltenVK

MoltenVK provides the ability to configure and optimize MoltenVK for your particular
application runtime requirements and development-time needs.

Additional configuration parameters can be helpful at development time by providing you with
additional tracing, debugging, and performance measuring capabilities.

Each configuration parameter has a name and value, and can be passed to MoltenVK
via any of the following mechanisms:

The standard Vulkan VK_EXT_layer_settings extension.
Application runtime environment variables.
Build settings at MoltenVK build time.

A description of each configuration parameter supported by MoltenVK can be found in the
MoltenVK_Configuration_Parameters.md document in the Docs directory.

Debugging Your MoltenVK Application using _Metal Frame Capture_

Since MoltenVK translates Vulkan API calls to Metal, you can use Apple's
Metal Frame Capture
to help debug your application. You can configure MoltenVK to automatically write to a GPU trace file,
without manual intervention, by using the following environment variables and configuration parameters:

METAL_CAPTURE_ENABLED=1, to enable Metal GPU capture. This must be set as an environment variable,
or in Xcode as an Option in the Scheme you use to launch your app from Xcode.
MVK_CONFIG_AUTO_GPU_CAPTURE_SCOPE=n, this defines the scope of the capture.
You can set n to:
- 0 to disable capturing,
- 1 to capture all frames created between the creation of a VkDevice to its destruction, or
- 2 to capture only the first frame.
MVK_CONFIG_AUTO_GPU_CAPTURE_OUTPUT_FILE=filename.gputrace, to set where the capture file
should be saved to. Note that filename.gputrace must not already exist, otherwise the file
will not be written, and an error will be logged.

Except for METAL_CAPTURE_ENABLED=1, the other parameters can be set as configuration parameters, as described
in the Configuring MoltenVK section above (including as environment variables).

The created capture file can then be opened with Xcode for investigation. You do not need to launch
your app from Xcode to capture and generate the trace file.

Metal Shading Language Shaders

Metal uses a different shader language than Vulkan. Vulkan uses the new
SPIR-V Shading Language (SPIR-V), whereas Metal uses the Metal Shading Language (MSL).
MoltenVK uses Runtime Shader Conversion to automatically convert your SPIR-V shaders
to their MSL equivalents, during loading your SPIR-V shaders, using the standard Vulkan
vkCreateShaderModule() function.

Troubleshooting Shader Conversion

The shader converter technology in MoltenVK is quite robust, and most SPIR-V shaders
can be converted to MSL without any problems. In the case where a conversion issue arises,
you can address the issue as follows:

Errors encountered during Runtime Shader Conversion are logged to the console.
To help understand conversion issues during Runtime Shader Conversion, you can enable logging
the SPIR-V and MSL shader source code during shader conversion, by enabing the MVK_CONFIG_DEBUG
configuration parameter. See the MoltenVK Configuration description above.

Enabling debug mode in MoltenVK includes shader conversion logging, which causes both
the incoming SPIR-V code and the converted MSL source code to be logged to the console
in human-readable form. This allows you to manually verify the conversions, and can help
you diagnose issues that might occur during shader conversion.
For some issues, you may be able to adjust your SPIR-V code so that it behaves the same
under Vulkan, but is easier to automatically convert to MSL.
You are also encouraged to report issues with shader conversion to the
SPIRV-Cross project. MoltenVK and
MoltenVKShaderConverter make use of SPIRV-Cross to convert SPIR-V shaders to MSL shaders.

Performance Considerations

This section discusses various options for improving performance when using MoltenVK.

Shader Loading Time

A number of steps is required to load and compile SPIR-V shaders into a form that Metal can use.
Although the overall process is fast, the slowest step involves converting shaders from SPIR-V to
MSL source code format.

If you have a lot of shaders, you can dramatically improve shader loading time by using the standard
Vulkan pipeline cache feature, to serialize shaders and store them in MSL form offline.
Loading MSL shaders via the pipeline cache serializing mechanism can be significantly faster than
converting from SPIR-V to MSL each time.

In Vulkan, pipeline cache serialization for offline storage is available through the
vkGetPipelineCacheData() and vkCreatePipelineCache() functions. Loading the pipeline cache
from offline storage at app start-up time can dramatically improve both shader loading performance,
and performance glitches and hiccups during runtime code if shader loading is performed then.

When using pipeline caching, nothing changes about how you load SPIR-V shader code. MoltenVK
automatically detects that the SPIR-V was previously converted to MSL, and stored offline via
the Vulkan pipeline cache serialization mechanism, and does not invoke the relatively expensive
step of converting the SPIR-V to MSL again.

Swapchains

Metal supports a very small number (3) of concurrent swapchain images. In addition, Metal can
sometimes hold onto these images during surface presentation.

MoltenVK supports using either 2 or 3 swapchain images. For best performance, it is recommended
that you use 3 swapchain images (triple-buffering), to ensure that at least one swapchain image will
be available when you need to render to it.

Using 3 swapchain images is particularly important when rendering to a full-screen surface, because
in that situation, Metal uses its Direct to Display feature, and avoids compositing the swapchain
image onto a separate composition surface before displaying it. Although Direct to Display can improve
performance throughput, it also means that Metal may hold onto each swapchain image a little longer
than when using an internal compositor, which increases the risk that a swapchain image will not be a
vailable when you request it, resulting in frame delays and visual stuttering.

Timestamping

On non-Apple GPUs (older Mac devices), the GPU can switch power and performance states as
required by usage. This affects the GPU timestamps retrievable through the Vulkan API.
As a result, the value of VkPhysicalDeviceLimits::timestampPeriod can vary over time.
Consider calling vkGetPhysicalDeviceProperties(), when needed, and retrieve the current
value of VkPhysicalDeviceLimits::timestampPeriod, to help you calibrate recent GPU
timestamps queried through the Vulkan API.

This is not needed on Apple Silicon devices, where all GPU timestamps are always returned
as nanoseconds, regardless of variations in power and performance states as the app runs.

Xcode Configuration

When a Metal app is running from Xcode, the default Scheme settings reduce performance.
Be sure to follow the instructions for configuring your application's Scheme within Xcode,
found in the in the installation section above.

Metal System Trace Tool

To help you get the best performance from your graphics app, the Xcode Instruments profiling tool
includes the Metal System Trace template. This template can be used to provide detailed tracing of the
CPU and GPU behaviour of your application, allowing you unprecedented performance measurement
and tuning capabilities for apps using Metal.

Known MoltenVK Limitations

This section documents the known limitations in this version of MoltenVK.

See above for known limitations for specific Vulkan extensions.
Image content in PVRTC compressed formats must be loaded directly into a VkImage using
host-visible memory mapping. Loading via a staging buffer will result in malformed image content.
Pipeline statistics query pool using VK_QUERY_TYPE_PIPELINE_STATISTICS is not supported.
Application-controlled memory allocations using VkAllocationCallbacks are ignored.
Since MoltenVK is an implementation of Vulkan functionality, it does not load
Vulkan Layers on its own. In order to use Vulkan Layers, such as the validation layers,
use the Vulkan Loader and Layers from the Vulkan SDK.
Refer to the Vulkan SDK Getting Started
document for more info.

File: Docs/Whats_New.md

What's New in MoltenVK

MoltenVK 1.4.3

Released TBD

Add support for the following extensions:
- VK_EXT_multi_draw
- VK_EXT_nested_command_buffer
- VK_EXT_ycbcr_2plane_444_formats
Fix inconsistent image memoryTypeBits when VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT is used.
Fix shader stage interface matching of 16-bit floating point variables.

MoltenVK 1.4.2

Released 2026-07-20

Add support for the following extensions:
- VK_EXT_sampler_filter_minmax on Apple10 GPUs with macOS 26 or iOS 26
Add gl_DrawID / DrawIndex support for MacOS.
Add native sampler min/max filtering.
Fix buffer and heap out-of-sync in initExternalMemory().
Fix incorrect varable usage in MVKImagePlane::getMTLTexture().
Fix incorrect placement heap check in MVKImagePlane::getMTLTexture().
Fix device loss when using imported MTLTexture objects with Metal argument buffers.
Raise minimum target to macOS 12.0 / iOS 15.0 / tvOS 15.0
Fix desync in primitive restart enable state tracking.
Fix inverted return logic in MVKBitArray::areAnyBitsSet().
Fix imported MTLTexture residency tracking.
Fix swapchain recreation giving 1x1 drawables.
Fix variable descriptor count query.
Fix channel corruption on Apple Silicon for color RTs used as transfer sources.
Fix behavior of VK_REMAINING_ARRAY_LAYERS with 2D array views of 3D images.
Fix invalidation of cached metal textures
Fix AMD subgroup size (64→32) and disable Intel UHD 630 simdReduction.
Fix incorrect placement heap check in MVKImagePlane::getMTLTexture().
Fix regressions and crashes on Mac 1 (NVIDIA/Intel) GPUs.
Disable 64-bit float control properties.
Disable non-working quad control flow.
Emulate reversed-depth viewports on affected AMD Mac GPUs.
Do not rely on extension enable for vkGetPhysicalDeviceToolPropertiesEXT procaddr.
Do not convert UINT8 indices until draw time.
Do not enable blending when unsupported by format.
Null-check pColorAttachmentInputIndices before reading.
Make imported MTLBuffer resident in MVKDeviceMemory.
Include Metal constant buffer alignment in argument buffer gpuAlign calculation.
Use max of pointer and constant buf alignments for arg buffer uniform.align field.
Only apply Metal Constant Buffer alignment to Aux Buffers and Combined Textures.
Apply Metal constant buffer alignment padding for each descriptor set.
MVKRenderPass: encode barriers for subpass dependencies.
Occlusion queries: wrap detection uses stale baseline, crashes when visibility buffer starts near end of pass.
Prevent null dereference in MVKPixelFormats.
Improve handling of draw ID buffer binding.
Restore some checks for Mac1 GPUs.
Update copyright notices to year 2026.
Update to latest SPIRV-Cross:
- MSL: add gl_DrawID (DrawIndex) support for macOS.
- MSL: Add reversed depth viewport emulation.
- MSL: Fix subgroupBallotExclusiveBitCount() is not available for task shader and mesh shader.
- MSL: thread_execution_width is deprecated as of Metal 3.0 , use threads_per_simdgroup instead.
- MSL: Add msl3.0 variant for subgroup builtin.
- MSL: Fix handling of variable pointer arguments which are not BDA.
- MSL: Fix variable pointer buffer arguments.
- MSL: Handle variable pointer argument to SSBO array.
- MSL: Fix handling of forced temporary row-major matrices.
- MSL: Additional MSL specific keywords(signed).
- MSL: Deal with std140 layouts when copying arrays between storage class.
- MSL: Rewrite std140 struct padding.
- MSL: BlockIO in vertex is captured as thread storage.
- MSL: Add initial cooperative matrix support.
- MSL: Fix ptr-cast prepass and coopmat typed load/store.
- MSL: Handle array type writes to builtin clip/cull better.
- MSL: Fix some extremely bizarre tess access chain bugs.
- MSL: Use pointer expression when dealing with atomics.
- Parser: support SPIR-V library modules without OpEntryPoint

MoltenVK 1.4.1

Released 2025-11-24

Add support for the following extensions:
- VK_KHR_maintenance9
- VK_KHR_shader_fma
- VK_KHR_surface_maintenance1
- VK_KHR_swapchain_maintenance1
Add support for new features and extensions when using MVK_USE_METAL_PRIVATE_API:
- Disabling primitive restart
- VK_EXT_legacy_dithering
- VK_EXT_non_seamless_cube_map
- VK_EXT_primitive_topology_list_restart
- VK_EXT_provoking_vertex
Improved occlusion query support:
- Add support for occlusion queries across multiple renderpasses.
- Improve performance by accumulating occlusion quieries in parallel,
  and using untracked buffers to avoid encoder serialization.
New descriptor state tracker implementation to improve performance.
New descriptor set/pool implementation:
- The new implementation is less forgiving of applications that don't properly manage the lifetime
  of their descriptors (and bind them after the objects they point to have been destroyed).
  Use MVK_CONFIG_LIVE_CHECK_ALL_RESOURCES=1 to revert any crashes this might cause,
  or mark potentially-destroyed descriptors with VK_DESCRIPTOR_BINDING_PARTIALLY_BOUND_BIT.
Add CMake build support.
Added working demo target for VisionOS in Cube Demo.
Raise minimum target to macOS 11.0 / iOS 14.0 / tvOS 14.0
Add support for VK_IMAGE_CREATE_BLOCK_TEXEL_VIEW_COMPATIBLE_BIT.
Reject image usages whose format features are not supported.
Return VK_ERROR_OUT_OF_POOL_MEMORY when running out of descriptor sets.
Make vkGetPhysicalDeviceToolProperties() an instance function.
Enable sample LOD bias for Xcode 26.
Update robustness support levels for different GPU types.
Update max texture dimensions for Apple10 GPU.
Allow host-coherent optimal tiling images on macOS with Apple GPU.
Add Metal4 and Apple10 GPU family logs.
Fix depth bounds test and logic op implementations.
Fix VkExternalMemory*CreateInfo not allowing host memory handle types.
Fix improper boundary error when requesting exactly the number of variable descriptors allocated.
Fix regression on functions used by multiple extensions.
Fix improper use of dynamic depth/stencil attachment.
Fix out-of-bound access when using multiview with multiple subpasses.
Fix vertexStrideAlignment value without Apple5.
Fix tvOS ASTC HDR formats.
Add base GPU family for samplerMipLodBias support.
Deprecate configuration parameter MVKConfiguration::supportLargeQueryPools and corresponding environment variable
MVK_CONFIG_SUPPORT_LARGE_QUERY_POOLS, as obsolete and ignored. Large query pools are now supported always.
Disable Mac Catalyst builds from all and all-debug in Makefile, due to unresolved issues with Mac Catalyst builds.
Add CI job for building for macOS with private API.
Update to latest SPIRV-Cross:
- MSL: Support image cube atomics on MSL 4.0+.
- MSL: Fix array copy to array inside stage IO Blocks.
- MSL: Fix boolean spec const as_type<> invalid output.
- MSL: Don't emit const device for readonly SSBO.
- MSL: Add some extra reserved function names.
- MSL: Support 64-bit subgroup shuffles.
- MSL: Get rid of obsolete buffer_aliases_argument vector.
- MSL: Ensure dynamic buffer offsets get a unique name.
- MSL: Fix missing use of add_local_variable_name for dynamic offset resources.
- MSL: Rethink how discrete variable count descriptor arrays are emitted.
- MSL: Throw on attempting to alias unrolled discrete descriptors.
- MSL: Fix mesh shader with no vertex outputs.
- MSL: Fix writing default gl_PointSize in tessellation shaders.
- MSL: Rethink "const device" handling.
- MSL: Narrow down which analysis passes need deep ID mapping.
- MSL: Support OpFmaKHR.

MoltenVK 1.4.0

Released 2025-08-20

Add support for Vulkan 1.4.
Add support for extensions:
- VK_KHR_dynamic_rendering_local_read
- VK_KHR_global_priority
- VK_KHR_line_rasterization
- VK_KHR_maintenance5
- VK_KHR_maintenance8
- VK_KHR_present_id
- VK_KHR_present_id2
- VK_KHR_present_wait
- VK_KHR_present_wait2
- VK_KHR_shader_float_controls2
- VK_KHR_shader_maximal_reconvergence
- VK_KHR_shader_quad_control
- VK_KHR_shader_relaxed_extended_instruction
- VK_KHR_shader_subgroup_uniform_control_flow
- VK_KHR_surface_protected_capabilities
- VK_EXT_line_rasterization
vkDeviceWaitIdle() & vkQueueWaitIdle() now wait even when VK_ERROR_DEVICE_LOST error is encountered.
For behaviouraly consistency, require deprecated unofficial extension VK_MVK_moltenvk be enabled to access
the proc addrs for functions vkSetMoltenVKConfigurationMVK() and vkGetPhysicalDeviceMetalFeaturesMVK().
Fix missed supported usage in image format properties checks.
Fix high latency on present wait.
Fix shader cache misses within pipeline cache.
Fix misalignment between pipeline pixel formats and dynamic rendering attachments.
Fix attempting to add memoryless images to residency sets.
Fix color-depth image copies and image copies using buffer with multiple layers.
Enable shaderRoundingModeRTEFloat16/32.
Move vkGetPhysicalDeviceMetalFeaturesMVK() from mvk_private_api.h to mvk_deprecated_api.h.
Re-expose proc addr for deprecated VK_MVK_moltenvk extension functions.
Add the AMD Radeon PRO W6800X as a device with 32-wide SIMD-groups.
Apple, AMD, and Intel devices use parallelograms for lines.
Fix counter set memory leak on workaround to AMD RDNA devices
Update to latest SPIRV-Cross:
- MSL: Add support for DebugPrintf.
- MSL: Fix crash due to regression caused by recent changes to location calculations.
- MSL: Add option to provide a default point size.
- MSL: Implement clustered subgroup operations for sizes other than 4.
- MSL: Fix generation of the WorkgroupSize built-in.
- MSL: Implement accurate OpSMod.
- MSL: Always emit gl_Layer for multiview.
- MSL: Don't emit const for BDA pointers.
- MSL: Fix loading BDA from std140 UBO.
- MSL: Fix issues with fp16 trancendentals.
- MSL: Fix edge case where a reference is taken of packed vector element.
- MSL: Fix crash when using force-native-arrays in some cases.
- MSL: Don't use fast::normalize for half at all.
- MSL: Implement atomic_thread_fence for MSL 3.2+.
- MSL: Always emit access qualifier when emitting coherency.
- MSL: Support SPIR-V Fast Math execution modes and decorations.
- MSL: Deal with spec constant arrays which depend on composite extract.
- MSL: Attempt to deal with float controls and trancendentals.
- MSL: Rethink add_pragma_line() and add_typedef_line().
- GLSL/MSL: Add support for SPV_KHR_quad_control.

MoltenVK 1.3.0

Released 2025-04-27

Add support for Vulkan 1.3.
Add support for extensions:
- VK_KHR_index_type_uint8
- VK_KHR_load_store_op_none
- VK_KHR_maintenance4
- VK_KHR_maintenance6
- VK_KHR_maintenance7
- VK_KHR_robustness2
- VK_KHR_shader_expect_assume
- VK_KHR_shader_subgroup_rotate
- VK_KHR_shader_terminate_invocation
- VK_KHR_vulkan_memory_model
- VK_KHR_zero_initialize_workgroup_memory
- VK_EXT_depth_clip_control
- VK_EXT_external_memory_metal.
- VK_EXT_image_2d_view_of_3d
- VK_EXT_index_type_uint8
- VK_EXT_load_store_op_none
- VK_EXT_pipeline_robustness
- VK_EXT_tooling_info
Add support for B5G6R5_UNORM_PACK16 B5G5R5A1_UNORM_PACK16, and B8G8R8A8 formats using swizzle.
Convert MVK_CONFIG_USE_MTLHEAP to enumeration, and set active by default to support
VK_EXT_image_2d_view_of_3d, except on AMD devices.
Remove glslang as dependency library.
MoltenVKShaderConverter no longer accepts GLSL` shaders as input.
Fixes to managing descriptor set allocation in a Metal argument buffer.
Fix SPIRV-Cross namespace build error on some alternate build environments.
Fix recent failure of CI.yml to upload release build artifacts to GitHub.
Fix memory management issue in MVKSwapchain.
Fix indirect index for triangle fan topology.
Fix crash when shader validation is enabled.
Fix dynamic vertex stride with tessellation.
Fix Metal API violation when using VK_KHR_swapchain_mutable_format.
Fix designation of vkGetPhysicalDeviceToolProperties as a device entry-point.
Fix memory leak of CAEDRMetadata in MVKSwapchain.
Fix not saving shouldFixupClipSpace when serializing a pipeline.
Fix header namespace pollution.
Revert use of size 1 for variable length arrays in shader.
Add MTLHeaps export/import for emulated textures.
MTLHeaps on Apple Device Simulator must use private storage.
Remove atomic usage for RG32Uint.
Handle shader specializtion with macros.
Use Metal residency sets when available.
Implement barriers using Metal fences.
vkCmdWaitEvents end current encoder before encodeWait.
Remove support for deprecated VK_NV_glsl_shader extension, and GLSL conversions using MoltenVKShaderConverter.
Remove use of VK_ERROR_INVALID_SHADER_NV error code.
Reduce number of unused pipeline bindings reserved for argument buffers.
Disable unsupported Metal Pixel formats for iOS/tvOS Simulator.
Revert to fixed number of argument buffer binding reservations.
Ignore allowed bad pViewportState pointer if rasterization is disabled.
Improved estimation of vertex attribute buffer count when reserving for implicit buffer.
Fix header-hygiene warning violations.
MVKCmdWaitEvents: end current encoder before encodeWait.
Add missing depthClamp and shaderTessellationAndGeometryPointSize features to tvOS.
Update features overrides to all Simulators: iOS, tvOS, visionOS.
Fix a crash when searching the first enabled bit in a completely disabled bit array.
When shader specifies both WorkgroupSize builtin and LocalSizeId, the builtin takes precedence.
When logging a pipeline layout, log contained descriptor set layouts.
Add debug labels to barrier fences.
Allow the proc address of vkGetMoltenVKConfigurationMVK() to be retrieved before a VkInstance has been created.
Work around 10.15 AMD driver's broken blit encoder timestamp sampling.
GitHub CI update legacy build to macOS 13 / Xcode 14.
Fix compile with MVK_USE_CEREAL=0.
Update copyright notices to year 2025.
Update to latest SPIRV-Cross:
- MSL: Support broader tessellation I/O matching for VK_KHR_maintenance4.
- MSL: Add support for SPV_KHR_expect_assume.
- GLSL/MSL: Implement SPV_KHR_subgroup_rotate.
- MSL: Implement subgroup clustered rotate.
- MSL: Pad array elements in Metal argument buffer when shader declares scalar.
- MSL: Expose information about specialization constants - macro mapping
- MSL: Use unpacked arguments in texture arguments.
- MSL: Fix emission of bindless helper template for bindless SSBO.
- MSL: Use actual result type member as cast type for mulhi.
- MSL: Terminate function with return value using return if ending in unreachable.
- MSL: Add option to disable rasterization depending on usage.
- MSL: Always pass BDA by value into functions.
- MSL: Apply input override on all flattened members in interface block.
- GLSL/MSL: Support VK_KHR_zero_initialize_workgroup_memory
- MSL: Treat pointer to vector as scalar type when bitcasting.
- MSL: Use the more proper pointer typing.
- MSL: Use decltype for getting return of gather.
- MSL: Remove spvForward().
- MSL: Fix gather functions on Sequoia.
- MSL: Fix crash when per-primitive variables are not used.

MoltenVK 1.2.11

Released 2024-10-01

Support dynamically allocating descriptors when pool is exhausted.
Deprecate MVKConfiguration::preallocateDescriptors and MVK_CONFIG_PREALLOCATE_DESCRIPTORS environment variable.
vkAllocateDescriptorSets(): Per Vulkan spec, if any descriptor set allocation
fails, populate all descriptor set pointers with VK_NULL_HANDLE. In addition,
return VK_ERROR_FRAGMENTED_POOL if failure was due to pool fragmentation.
vkUpdateDescriptorSets(): Per Vulkan spec, allow write or copy beyond the
end of a descriptor binding count, including inline uniform block descriptors.
Update VkFormat capabilities based on latest Metal docs.
Ensure all MoltenVK config info set by VK_EXT_layer_settings is used.
Advertise VK_FORMAT_FEATURE_2_STORAGE_READ_WITHOUT_FORMAT_BIT and
VK_FORMAT_FEATURE_2_STORAGE_WRITE_WITHOUT_FORMAT_BIT for storage texel buffers.
Support storage images in Metal argument buffers on iOS.
vkUpdateDescriptorSets(): Support writing beyond descriptor binding size if subsequent bindings are of same type.
Fix rendering issue with render pass that immediately follows a kernel dispatch.
Fix occasional GPU crash when a smaller descriptor set replaces a larger one.
Fix race condition when VkImage destroyed while used by descriptor.
Fix crash in vkCmdPushDescriptorSetWithTemplateKHR() when entries in
VkDescriptorUpdateTemplateCreateInfo are not sorted by offset.
Fix issue where vkQueueWaitIdle() and vkDeviceWaitIdle() were not
waiting for all commands to be enqueued before enqueuing wait operation.
Fix occassional incorrect detection of available descriptor sets during vkAllocateDescriptorSets().
Fix shader conversion failure when using storage images on iOS & tvOS with Tier 1 argument buffer support.
Fix occasional memory leak where spurious texel buffer was accidentally created during image-memory unbinding.
Fix memory leak in debug utils messenger.
Fix crash when VkDescriptorSetLayout is destroyed while descriptor set is in use.
Fix build failure on VisionOS 2.0 platform.
Support VK_FORMAT_A2B10G10R10_UNORM_PACK32 and VK_FORMAT_A2R10G10B10_UNORM_PACK32 formats as surface formats on all platforms.
Add MTLStoreAction mapping for VK_ATTACHMENT_STORE_OP_NONE.
Add estimate of presentMargin in returned data from vkGetPastPresentationTimingGOOGLE().
Update value of minSubgroupSize on AMD RX6600 to 32.
Fix support for running on tvOS 13.
Only add present handler if VK_GOOGLE_display_timing info is available during presentation.
Move primitive-restart-disabled warning from renderpass to pipeline creation, to reduce voluminous log noise.
iOS: Support storage images in Metal argument buffers.
Add MVKConfiguration::shaderLogEstimatedGLSL, and environment variable MVK_CONFIG_SHADER_LOG_ESTIMATED_GLSL,
to enable or disable the logging of estimated GLSL code, and disable it by default
Fix endless loop in fetchDependencies when -- is missing on platform names.
Update dependency libraries to match Vulkan SDK 1.3.296.
Update MVK_PRIVATE_API_VERSION to version 43.
Update to latest SPIRV-Cross:
- Various non-feature maintenance updates.

MoltenVK 1.2.10

Released 2024-07-15

Improvements to bindless resources and descriptor indexing:
- Add support for Metal 3 argument buffers.
- Support argument buffers on all platforms, when Metal 3 is available.
- Support argument buffers on macOS when Metal 3 is not available.
- Use Metal argument buffers by default when they are available.
- Revert MVKConfiguration::useMetalArgumentBuffers and env var
  MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS to a boolean value, and enable it by default.
- Support multiplanar images in Metal argument buffers.
- Support a descriptor pool with less descriptors than the descriptor set layout,
  as long as the pool has enough descriptors for the variable descriptor count,
- Update max number of bindless buffers and textures per stage to 1M, per Apple Docs.
- Track OpArrayLength buffer-sizes buffer as an auxiliary buffer in each descriptor set
  argument buffer, as this is how SPIRV-Cross expects it.
Add option to generate a GPU capture via a temporary named pipe from an external process.
Fix shader conversion failure when using native texture atomics.
MSL shader conversion, only pass resource bindings that apply to current shader stage.
Graphics pipeline better support dynamic patch control points.
Fix crash when VkPipelineShaderStageCreateInfo::pTessellationState is null.
Update documentation for minimum runtime OS requirements to indicate macOS 10.15, iOS 13, or tvOS 13.
Add support for Xcode 16, macOS 15 SDK, iOS 18 SDK, and MSL 3.2.
Enforce barrier when sampling timestamps.
Update Github CI versions to use Github's latest macOS and default Xcode,
and update legacy CI support to macOS 12 and Xcode 13.4.1.
Update dependency libraries to match Vulkan SDK 1.3.290.
Update MVK_PRIVATE_API_VERSION to version 42.
Update to latest SPIRV-Cross:
- MSL: Add option to force depth write in fragment shaders
- MSL: Improve handling of padded descriptors with argument buffers
- MSL: Support ConstOffsets on image gather.
- MSL: Image gather ConstOffsets supports multiple address spaces.
- MSL: Support a runtime array with dynamic offset in an argument buffer.
- MSL: Support descriptor sets with recursive content when using argument buffers.
- MSL: Don't bother supporting invalid multi-dimensional dynamic buffers.
- MSL: Do not overwrite rez_bind when padding.
- MSL: Only consider padding for non-aliased resources.
- MSL: Always use layout-declared array size for argument buffers.
- MSL: Allow UBO/SSBO resources to get the layout-derived size as well.
- MSL: Improve handling of padded descriptors with argument buffers.
- MSL: Fix invalid packing for pointer-to-vector.
- MSL: Handle OpPtrAccessChain with ArrayStride
- MSL: Consider pointer arithmetic for OpPtrAccessChain.
- MSL: Cast to packed format when using unexpected stride.
- MSL: Minor fix to resource type of spvBufferSizeConstants array indexes.

MoltenVK 1.2.9

Released 2024/05/07

Add support for extensions:
- VK_EXT_host_image_copy
To support legacy apps, restore MoltenVK/dylib directory via symlink to MoltenVK/dynamic/dylib.
Enhancements to MVKPerformanceStatistics. Add MVKPerformanceTracker::previous,
MVKQueuePerformance::waitSubmitCommandBuffers, and MVKQueuePerformance::waitPresentSwapchains.
Add MVK_CONFIG_SHADER_DUMP_DIR configuration parameter to optionally dump shaders to files.
Return MoltenVK log level string in pMessageIdName field of debug utils callback data.
Fix crash when using VK_EXT_metal_objects under ARC.
Fix deadlock when creating a swapchain on a thread other than the main thread.
Fix potential memory leak in vkQueueWaitIdle().
Fix argument buffer padding on shader conversion.
Avoid atomic image usage if native atomics are not supported on the platform.
Ensure buffer bindings are actually used to avoid potential overrun on Metal buffer indexes.
Update dependency libraries to match Vulkan SDK 1.3.283.
Update MVK_PRIVATE_API_VERSION to 41.
Update to latest SPIRV-Cross:
- MSL: Add support for overlapping bindings.
- MSL: Use recursive template for spvArrayCopy().
- MSL: Improve argument buffer descriptor aliasing implementation.
- MSL: Workaround compiler issue with image fence when used as reference.
- MSL: Fix SUMulExtended for 64-bit inputs.
- MSL: Handle Atomic{S,U}{Min,Max} with mismatched image sign.
- MSL: Handle missing FP16 trancendental overloads.
- MSL: Remove pointer wrapper stored in spvDescriptorArray() to avoid potential Metal compiler bug.
- MSL: Fix argument buffer padding.

MoltenVK 1.2.8

Released 2024/03/12

Add support for extensions:
- VK_KHR_shader_integer_dot_product
Improve support for iOS App Store rules by using dynamic XCFramework, instead of naked dylib.
- Static XCFramework now available in Package/Latest/MoltenVK/static/MoltenVK.xcframework.
- Dynamic XCFramework now available in Package/Latest/MoltenVK/dynamic/MoltenVK.xcframework.
- macOS dynamic library now available in Package/Latest/MoltenVK/dynamic/dylib/macOS/libMoltenVK.dylib.
Add MVK_USE_METAL_PRIVATE_API build setting to allow MoltenVK to be built with access to Metal private API calls.
- VkPhysicalDeviceFeatures::wideLines enabled when MVK_USE_METAL_PRIVATE_API is enabled in a MoltenVK build.
- VkPhysicalDeviceFeatures::logicOp enabled when MVK_USE_METAL_PRIVATE_API is enabled in a MoltenVK build.
- VkPhysicalDeviceFeatures::depthBounds enabled on AMD GPUs when MVK_USE_METAL_PRIVATE_API is enabled in a MoltenVK build.
- VkPhysicalDevicePortabilitySubsetFeaturesKHR::samplerMipLodBias enabled when MVK_USE_METAL_PRIVATE_API is enabled in a MoltenVK build.
- Metal native pipeline sample masks supported when MVK_USE_METAL_PRIVATE_API is enabled in a MoltenVK build.
Enable use of native texture atomics where supported.
Fix potential crash when using multi-planar images.
Fix translation of fully remapped multi vertex attribute bindings.
Fix unresolvable layered compute resolve.
Fix visionOS build.
Handle depth/stencil swizzle sample correctly.
Ensure buffers available for buffer addresses in push constants.
Don't update currentExtent of headless surface when swapchain attached.
Don't return VK_SUBOPTIMAL_KHR for headless surfaces.
runcts script also output a file containing a list of the failed CTS tests.
Add documentation for using Metal GPU capture with MoltenVK.
Update minimum macOS deployment target to 10.15.
Update minimum iOS/tvOS deployment target to 13.0.
Update dependency libraries to match Vulkan SDK 1.3.280.
Update MVK_PRIVATE_API_VERSION to 40.
Update to latest SPIRV-Cross:
- MSL: Plumb through member state to image/sampler types.
- MSL: Support variable sized descriptor array in argument buffer.
- MSL: Implement spvDescriptorArray path for SSBO/UBO.
- MSL: Add support for SPV_EXT_integer_dot_product.
- MSL: Fix misc sign issues with dot product impl and add more coverage.
- MSL: Handle volatile properly for emulated image atomics.
- MSL: OpCopyObject declare a temp var of base type, not pointer type.
- MSL: Pass texture array index separately to atomic texture operations.
- MSL: Test image atomic for image2DArray.
- MSL: Improve handling of BDA + atomics.
- MSL: Fix type hierarchy for extended vectors.
- MSL: Fix type hierarchy for extended vectors.
- MSL: atomic_compare_exchange_weak() support CompilerMSL:msl_options.texture_1D_as_2D.

MoltenVK 1.2.7

Released 2024/01/08

Add support for extensions:
- VK_KHR_calibrated_timestamp
- VK_KHR_format_feature_flags2
- VK_KHR_vertex_attribute_divisor
- VK_EXT_extended_dynamic_state3 (Metal does not support VK_POLYGON_MODE_POINT)
- VK_EXT_headless_surface
- VK_EXT_layer_settings
Add support for format VK_FORMAT_B4G4R4A4_UNORM_PACK16.
Add support for vertex formats VK_FORMAT_B10G11R11_UFLOAT_PACK32 & VK_FORMAT_E5B9G9R9_UFLOAT_PACK32.
Fix regression that broke VK_POLYGON_MODE_LINE.
Fix regression in marking rendering state dirty after vkCmdClearAttachments().
Fix regression error in argument buffer runtime arrays.
Fix rare deadlock during launch via dlopen().
Fix initial value of VkPhysicalDeviceLimits::timestampPeriod on non-Apple Silicon GPUs.
Fix swapchain and surface bugs when windowing system is accessed from off the main thread.
Fix system memory size of tvOS.
Fix heapUsage query for non-unified memory devices.
Add a defensive guard to ensure heapUsage[0] calculation is correct.
Clamp max per-set descriptor limit to minimum 1024.
Enable the cube texture gradient workaround for Apple Silicon.
Ensure lineWidthGranularity is zero if the wideLines feature isn't supported.
Ensure maxDrawIndexedIndexValue set to UINT32_MAX.
Ignore no external handle types specified for buffers and images.
Expose VK_EXT_debug_utils device functions as device functions, not instance functions.
Emit primitiveRestartEnable disabled warning only for strip topology.
Enable mandatory VK_EXT_descriptor_indexing features, and don't advertise extension if they are not supported.
Reduce disk space consumed after running fetchDependencies script by removing intermediate file caches.
Deprecate vkSetMoltenVKConfigurationMVK().
Deprecate mvk_config.h and move content to mvk_private_api.h and mvk_deprecated_api.h.
The Cube demo is now based on Volk, with dynamic library linking, and dynamic function pointer calls.
Update copyright notices to year 2024.
Update dependency libraries to match Vulkan SDK 1.3.275.
Update MVK_CONFIGURATION_API_VERSION and MVK_PRIVATE_API_VERSION to 39.
Update to latest SPIRV-Cross:
- MSL: Fix regression error in argument buffer runtime arrays.
- MSL: Work around broken cube texture gradients on Apple Silicon.
- MSL: Ensure discrete runtime arrays of buffers have known length.
- MSL: Implement Metal 3.1 image atomics natively.
- MSL: Fix patch vertex count with raw buffer tese input.
- MSL: Improve handling of sample masks.
- MSL: Add divide to reserved function names.
- MSL: Support std140 half matrices and arrays.
- MSL: Use more appropriate padded types.
- MSL: Don't use swizzle if we have wrapper.
- MSL: Add ray-cull mask
- MSL: Consider PtrAccessChain on array types.
- MSL: Use LHS expression to determine whether or not to do array copy.
- MSL: Only do address-of expression when needed.
- MSL: Improve PtrAccessChain handling.
- MSL: Use powr instead of pow.
- MSL: Remove special case for threadgroup array wrapper.
- MSL: Added an Op field to SPIRType and refactor.

MoltenVK 1.2.6

Released 2023/10/17

Add support for extensions:
- VK_KHR_synchronization2
- VK_EXT_extended_dynamic_state (requires Metal 3.1 for VK_DYNAMIC_STATE_VERTEX_INPUT_BINDING_STRIDE)
- VK_EXT_extended_dynamic_state2
Fix rare case where vertex attribute buffers are not bound to Metal when no other bindings change between pipelines.
Ensure objects retained for life of MTLCommandBuffer during vkCmdBlitImage() & vkQueuePresentKHR().
Fix case where a CAMetalDrawable with invalid pixel format causes onscreen flickering.
Fix deadlock when reporting debug message on MVKInstance destruction.
Fix MSL code used in vkCmdBlitImage() on depth-stencil formats.
Improve behavior of swapchain image presentation stalls caused by Metal regression.
VkPhysicalDeviceLimits::timestampPeriod set to 1.0 on Apple GPUs, and calculated dynamically on non-Apple GPUs.
Add MVKConfiguration::timestampPeriodLowPassAlpha and environment variable
MVK_CONFIG_TIMESTAMP_PERIOD_LOWPASS_ALPHA, to add a configurable lowpass filter
for varying VkPhysicalDeviceLimits::timestampPeriod on non-Apple GPUs.
Add several additional performance trackers, available via logging, or the mvk_private_api.h API.
Deprecate MVK_DEBUG env var, and add MVK_CONFIG_DEBUG env var to replace it.
Update MVK_CONFIGURATION_API_VERSION and MVK_PRIVATE_API_VERSION to 38.
Update dependency libraries to match Vulkan SDK 1.3.268.
Update to latest SPIRV-Cross:
- MSL: Workaround Metal 3.1 regression bug on recursive input structs.
- MSL: fix extraction of global variables, in case of atomics.
- MSL: Workaround bizarre crash on macOS.
- MSL: runtime array over argument buffers.
- MSL: Make rw texture fences optional.
- MSL: Prevent RAW hazards on read_write textures.

MoltenVK 1.2.5

Released 2023/08/15

Add support for extensions:
- VK_KHR_deferred_host_operations
- VK_KHR_incremental_present
- VK_KHR_shader_non_semantic_info
- VK_EXT_4444_formats
- VK_EXT_calibrated_timestamps
- VK_EXT_pipeline_creation_feedback
- VK_EXT_shader_demote_to_helper_invocation
- VK_EXT_shader_subgroup_ballot
- VK_EXT_shader_subgroup_vote
Add support for VK_PRIMITIVE_TOPOLOGY_TRIANGLE_FAN.
Support building MoltenVK for visionOS.
Ensure non-dispatch compute commands don't interfere with compute encoding state used by dispatch commands.
Support maximizing the concurrent executing compilation tasks via MVKConfiguration::shouldMaximizeConcurrentCompilation
Support VK_PRESENT_MODE_IMMEDIATE_KHR if VkPresentTimeGOOGLE::desiredPresentTime is zero.
Add support for VK_PRESENT_MODE_IMMEDIATE_KHR to macOS Cube demo.
Allow both renderPass and VkPipelineRenderingCreateInfo to be missing.
Fix sync delay between calls to vkQueueSubmit() on non-Apple-Silicon devices.
Ensure Xcode simulator always uses 256B buffer alignment.
Don't attempt to force the window system to use the same high-power GPU as the app, on every swapchain creation.
Log more info about SPIR-V to MSL conversion errors.
Implement Deferred Host Operations.
Support MSL Version 3.1.
Drop official support for using Xcode 11 to build MoltenVK.
To allow building MoltenVK without an internet connection, don't fetch a submodule if the commit is already known.
Update dependency libraries to match Vulkan SDK 1.3.261.
Update to latest SPIRV-Cross:
- MSL: Fix argument buffer padding when content includes arrays.
- MSL: ray-query intersection params
- MSL: Support SPV_KHR_shader_ballot and SPV_KHR_subgroup_vote.
- Skip line directives when emitting loop condition blocks.
- MSL: Consider changed array types for array-of-constant-bool in struct.
- MSL: Consider bool-short remapping for constant expressions as well.
- Minor cleanup in constant_expression().
- MSL: Add test for bool-in-struct edge cases.
- MSL: Handle more complex array copy scenarios with bool <-> short.
- MSL: Handle stores to struct bool[].
- MSL: Consider bool/short remapping when dealing with composites.
- MSL: fix function constant deduplication misfire

MoltenVK 1.2.4

Released 2023/05/23

Add support for extensions:
- VK_KHR_map_memory2
Deprecate the obsolete and non-standard VK_MVK_moltenvk extension.
- Add mvk_config.h, mvk_private_api.h, and mvk_deprecated_api.h, and deprecate vk_mvk_moltenvk.h.
Support BC compression on iOS/tvOS where available (iOS/tvOS 16.4 and above and supported by the GPU).
Support separate depth and stencil attachments during dynamic rendering.
Fix memory leak when waiting on timeline semaphores.
Fix race condition when updating values in VkPastPresentationTimingGOOGLE,
and ensure swapchain image presented time is always populated when requested.
Report error, but do not fail on request for timestamp query pool that is too
large for MTLCounterSampleBuffer, and fall back to emulation via CPU timestamps.
Ensure shaders that use PhysicalStorageBufferAddresses encode the use of the associated MTLBuffer.
Disable pipeline cache compression prior to macOS 10.15 and iOS/tvOS 13.0.
Accumulate render stages when a resource is used by multiple descriptor bindings.
Respect the bind point supplied to vkCmdBindDescriptorSets() / vkCmdPushDescriptorSets().
Check if shader compiled before adding it to a pipeline, to avoid Metal validation error.
Identify each unsupported device feature flag that the app attempts to enable.
Populate deviceUUID from MTLDevice location and peer group info,
which should be unique, and constant across OS reboots.
Populate deviceLUID from MTLDevice.registryID.
Avoid Metal validation warning when depth component swizzled away.
Fix depth clamp and texture swizzle feature discovery on simulator builds.
Advertise VK_KHR_depth_stencil_resolve extension on all devices.
For correctness, set VkPhysicalDeviceLimits::lineWidthGranularity to 1.
Improve GitHub CI production of binary artifacts on submission and release.
Update dependency libraries to match Vulkan SDK 1.3.250.
Update to latest SPIRV-Cross:
- MSL: Fix for argument buffer index compare when invalid.
- MSL: Fix dref lod workaround on combined texture/samplers.
- MSL: Do not override variable name with v_ identifier.
- MSL: Use name_id consistently in argument declaration.
- MSL: Don't hit array copy path for pointer to array.
- MSL: Use templated array type when emitting BDA to arrays.

MoltenVK 1.2.3

Released 2023/03/22

Add support for extensions:
- VK_EXT_external_memory_host
- VK_EXT_pipeline_creation_cache_control
- VK_EXT_shader_atomic_float
- VK_EXT_surface_maintenance1
- VK_EXT_swapchain_maintenance1
Fix crash when VkCommandBufferInheritanceInfo::renderPass is VK_NULL_HANDLE during dynamic rendering.
Do not clear attachments when dynamic rendering is resumed.
Allow ending dynamic rendering to trigger next multiview pass if needed.
Fix premature caching of occlusion query results during tessellation rendering.
vkCmdCopyQueryPoolResults(): Fix loss of queries when query count is not a multiple of GPU threadgroup execution width.
Disable occlusion recording while clearing attachments or render area.
Fix issue where extension VK_KHR_fragment_shader_barycentric was sometimes incorrectly disabled due to a Metal driver bug.
Detect when size of surface has changed under the covers.
Change rounding of surface size provided by Metal from truncation to rounding-with-half-to-even.
Queue submissions retain wait semaphores until MTLCommandBuffer finishes.
Use a different visibility buffer for each MTLCommandBuffer in a queue submit.
Work around problems with using explicit LoD with arrayed depth images on Apple Silicon.
Fix issue when VkPipelineVertexInputDivisorStateCreateInfoEXT::vertexBindingDivisorCount
doesn't match VkPipelineVertexInputStateCreateInfo::vertexBindingDescriptionCount.
Support Apple Silicon pixel formats on a MoltenVK x86_64 build that is running on Apple Silicon using Rosetta2.
Reduce memory footprint of MSL source code retained in pipeline cache.
Add MVKConfiguration::shaderSourceCompressionAlgorithm and
env var MVK_CONFIG_SHADER_COMPRESSION_ALGORITHM to support
compressing MSL shader source code held in a pipeline cache.
Add MVKShaderCompilationPerformance::mslCompress and mslDecompress
to allow performance of MSL compression to be tracked and queried.
Add support for logging performance stats accumulated in a VkDevice, when it is destroyed.
Change MVKConfiguration::logActivityPerformanceInline boolean to activityPerformanceLoggingStyle enumeration value.
Add MVK_CONFIG_ACTIVITY_PERFORMANCE_LOGGING_STYLE environment variable and
build setting to set MVKConfiguration::activityPerformanceLoggingStyle value.
Expand MVK_CONFIG_TRACE_VULKAN_CALLS to log thread ID only if requested.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 37.
Update dependency libraries to match Vulkan SDK 1.3.243.
Update to latest SPIRV-Cross:
- MSL: Add support for OpAtomicFAddEXT atomic add on float types
- MSL: Add a workaround for broken level() arguments.
- MSL: Deduplicate function constants.

MoltenVK 1.2.2

Released 2023/01/23

Fix Metal validation error caused by CAMetalDrawable released before
MTLCommandBuffer is finished using it.
Fix memory leak of MVKFences and MVKSemaphores when
a swapchain image is acquired more than it is presented.
Fix issue where fragment shader was not run when no render attachment is available.
Ensure Vulkan public symbols are not stripped from the library when
statically linked to an app that calls all Vulkan functions dynamically.
Per Vulkan 1.2 spec, support calling vkGetInstanceProcAddr() with a
null instance, when vkGetInstanceProcAddr itself is the function name.
Update VkPhysicalDeviceLimits members maxClipDistances and
maxCombinedClipAndCullDistances to more accurate values.
Update VkPhysicalDeviceLimits::maxDrawIndexedIndexValue to
acknowledge automatic primitive restart.
Update copyright notices to year 2023.
Update dependency libraries to match Vulkan SDK 1.3.239.
Update to latest SPIRV-Cross:
- MSL: Add support for writable images in iOS Tier2 argument buffers.
- MSL: Fix potentially uninitialized warnings.

MoltenVK 1.2.1

Released 2022/12/08

Add support for extensions:
- VK_KHR_copy_commands2
Fix crash on descriptor update with out-of-bounds descriptor count data.
Fix Metal buffer index binding overrides for push constants and attachment clearing.
Fix crash when buffer binding updates only offset while it is overridden.
Fix app performance regression triggered by the previous introduction of VK_KHR_shader_float_controls.
Work around MTLCounterSet crash on additional Intel Iris Plus Graphics devices.
Fix mistaken YCBCR format support indication.
Fix invalid blit offsets.
Wait on emulated semaphores only once to prevent freezing when using prefilled command buffers.
MVKPipeline: Stop using vertex-style input for tessellation evaluation shaders.
MVKPipeline: Force extra checks for stores after fragment discard.
MVKImage: Always use a texel buffer for atomic storage images.
MVKDevice: Fix backwards attribution of storage/uniform texel buffer alignments.
Document new linkage model used by Xcode 14 and later, and how to link MoltenVK
to an app or game using Xcode 13 or earlier.
Support Xcode 14.1 build settings.
Upgrade GitHub CI to use Xcode 14.1 on macOS 12.
Update dependency libraries to match Vulkan SDK 1.3.236.
Update to latest SPIRV-Cross:
- MSL: Implement CompositeInsert OpSpecConstantOp.
- MSL: Support "raw" buffer input in tessellation evaluation shaders.
- MSL: Don't flatten arrayed per-patch output blocks in tessellation shaders.
- MSL: Account for composite types when assigning locations.
- MSL: Handle partial access chains with array-of-UBO/SSBO.
- MSL: Fix restrict vs __restrict incompatibility.
- MSL: Handle implicit integer promotion rules.
- MSL: Manually update BuiltInHelperInvocation when a fragment is discarded.
- MSL: Add missing casts to Op?MulExtended.
- MSL: Prevent stores to storage resources in discarded fragments.
- MSL: Don't dereference forwarded copies of OpVariable pointers.
- MSL: Refactor member reference in terms of one boolean.
- Fix MSL Access Chain.

MoltenVK 1.2.0

Released 2022/10/17

Add support for Vulkan 1.2.
Add support for extensions:
- VK_KHR_shader_float_controls
- VK_KHR_spirv_1_4
Vulkan semaphore functional improvements:
- Replace use of MTLFence with an option to limit to a single Vulkan queue and use Metal's implicit submisison order guarantees.
- Support option to force use of MTLEvents for Vulkan semaphores on NVIDIA and Rosetta2.
- MVKConfiguration replace booleans semaphoreUseMTLEvent and semaphoreUseMTLFence with enumerated semaphoreSupportStyle.
Support config option to automatically use Metal argument buffers when VK_EXT_descriptor_indexing
extension is enabled. MVKConfiguration::useMetalArgumentBuffers (MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS)
is now an enum field. The use of Metal argument buffers is still disabled by default (MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS_NEVER).
Fix memory leaks when configured for prefilling Metal command buffers.
MVKConfiguration replace boolean prefillMetalCommandBuffers with enumeration.
MVKPipeline: Add builtins that are read but not written to tessellation pipelines.
Fix occassional crash from retention of MVKSwapchain for future drawable presentations.
Fix crash in vkCreateSwapchainKHR() on macOS 10.14 and earlier
Fix undefined reference to vkGetBufferDeviceAddressEXT when building with MVK_HIDE_VULKAN_SYMBOLS=1.
Update Makefile to forward any build setting declared on the command line to Xcode.
Add non-functional Vulkan 1.3 core function stubs, to avoid link errors with some external
libraries that assume Vulkan 1.3 linkages from the standard Vulkan header files included with MoltenVK.
Add MVK_USE_CEREAL build setting to avoid use of Cereal external library (for pipeline caching).
MoltenVKShaderConverter tool automatically maps bindings when converting GLSL.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 36.
Update to latest SPIRV-Cross:
- MSL: Support OpPtrEqual, OpPtrNotEqual, and OpPtrDiff.
- MSL: Emit correct address space when casting during OpStore.
- MSL: Add a mechanism to fix up shader outputs.
- MSL: Handle descriptor aliasing of raw buffer descriptors.
- MSL: Do not attempt to alias push constants.
- MSL: only fix up gl_FragCoord if really necessary.
- MSL: Expose way to query if a buffer needs array length.
- MSL: Report unsupported 64-bit atomics.
- Don't rename remapped variables like gl_LastFragDepthARM

MoltenVK 1.1.11

Released 2022/08/15

Add support for extensions:
- VK_EXT_metal_objects
- VK_KHR_buffer_device_address and VK_EXT_buffer_device_address (available on GPUs with Tier 2 argument buffers support).
Reducing redundant state changes to improve command encoding performance.
Improve performance of vkResetDescriptorPool().
Update minimum Xcode deployment targets to macOS 10.13, iOS 11, and tvOS 11,
to avoid Xcode build warnings in Xcode 14.
Work around MTLCounterSet crash on additional Intel Iris Plus Graphics drivers.
Check MTLDevice to enable support for VK_KHR_fragment_shader_barycentric
and VK_NV_fragment_shader_barycentric extensions.
Ignore sampler update in descriptor set bindings that use immutable samplers.
Fix query pool wait block when query is not encoded to be written to.
Fix vkUpdateDescriptorSetWithTemplate() for inline block descriptors.
Fix retrieval of accurate vkGetRefreshCycleDurationGOOGLE() across multiple display screens.
Fix occasional missing Metal buffer binding when only offset changes.
Fix crash creating compute pipelines on macOS versions < 10.14.
Apply Apple fix to MTLCaptureScope retention bug to macOS 12.4 and iOS 15.4 and later.
Report appropriate values of VkDebugUtilsMessageTypeFlagsEXT for debug util messages generated within MoltenVK.
Update macOS Cube demo to demonstrate optimizing the swapchain across multiple display screens.
Support building in Xcode 14.
Allow building on removable volumes with a space in their name.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 35.
Update to latest SPIRV-Cross:
- MSL: Add support for SPV_KHR_physical_storage_buffer extension.
- MSL: Use a wrapper type for matrices in workgroup storage.
- MSL: Fix various bugs with Ptr/U bitcasts.
- Fix control flow bug with missed continue statement.
- Handle PHI in collapsed switch constructs.
- Handle collapsed loops similar to collapsed selections.
- Handle multiple breaks out of switches.
- Do not optimize OpCompositeInsert for hoisted temporaries.

MoltenVK 1.1.10

Released 2022/06/06

Add support for extensions:
- VK_KHR_portability_enumeration support added to MoltenVK_icd.json, and documentation
  updated to indicate the impact of the VK_KHR_portability_enumeration extension during
  runtime loading on macOS via the Vulkan Loader.
- VK_KHR_dynamic_rendering
- VK_KHR_fragment_shader_barycentric and VK_NV_fragment_shader_barycentric
- VK_KHR_separate_depth_stencil_layouts
- VK_EXT_separate_stencil_usage
Implement vkGetRefreshCycleDurationGOOGLE() for macOS.
Support attachment clearing when some clearing formats are not specified.
Fix regression error where previously bound push constants can override a descriptor buffer
binding used by a subsequent pipeline that does not use push constants.
Fix error on some Apple GPU's where a vkCmdTimestampQuery() after a renderpass was
writing timestamp before renderpass activity was complete.
Fix regression error in vertex buffer binding counts when establishing implicit buffers binding indexes.
Fix vkSetMoltenVKConfigurationMVK() function pointer typedef.
Work around zombie memory bug in Intel Iris Plus Graphics driver when repeatedly retrieving GPU counter sets.
Fix reorder-ctor warnings and add Xcode clang -Wreorder warning to catch future misalignments.
Update build settings to support Xcode 13.4.
Update to latest SPIRV-Cross:
- MSL: Emit interface block members of array length 1 as arrays instead of scalars.
- MSL: Potentially cast loaded Input variables.
- Emit KHR barycentrics if source enables the KHR extension.
- Handle early reads from loop variables with initializers.
- Attempt more optimal codegen for OpCompositeInsert.

MoltenVK 1.1.9

Released 2022/04/11

Add support for extensions:
- VK_EXT_sample_locations (Custom locations settable via vkCmdBeginRenderPass() only,
  since VkPhysicalDeviceSampleLocationsPropertiesEXT::variableSampleLocations is false).
Fixes to pipeline layout compatibility between sequentially bound pipelines.
Reinstate memory barriers on non-Apple GPUs, which were inadvertently disabled in an earlier update.
Support base vertex instance support in shader conversion.
Fix alignment between outputs and inputs between shader stages when using nested structures.
Fix issue where the depth component of a stencil-only renderpass attachment was incorrectly attempting to be stored.
Fix deletion of GPU counter MTLFence while it is being used by MTLCommandBuffer.
Fix crash in vkGetMTLCommandQueueMVK().
Fix leak of CoreFoundation objects during calls to vkUseIOSurfaceMVK().
Remove limit on VkPhysicalDeviceLimits::maxSamplerAllocationCount when not using Metal argument buffers.
Avoid adjusting SRGB clear color values by half-ULP on GPUs that round float clear colors down.
Fixes to optimize resource objects retained by descriptors beyond their lifetimes.
Optimize behavior for VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT when
MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS is used
MoltenVKShaderConverter tool defaults to the highest MSL version supported on runtime OS.
Update glslang version, to use python3 in glslang scripts, to replace missing python on macOS 12.3.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 34.
Update to latest SPIRV-Cross:
- MSL: Support input/output blocks containing nested struct arrays.
- MSL: Use var name instead of var-type name for flattened interface members.
- MSL: Handle aliased variable names for resources placed in IB struct.
- MSL: Handle awkward mix and match of Offset / ArrayStride in constants.
- MSL: Append entry point args to local variable names to avoid conflicts.
- MSL: Consider that gl_IsHelperInvocation can be Volatile.
- MSL: Refactor and fix use of quadgroup vs simdgroup.
- Handle OpTerminateInvocation.
- Fixup names of anonymous inner structs.
- Fix regression from adding 64-bit switch support.

MoltenVK 1.1.8

Released 2022/02/22

Remove logged warning if MoltenVK does not support VkApplicationInfo::apiVersion value.

MoltenVK 1.1.7

Released 2022/02/07

Add MVK_HIDE_VULKAN_SYMBOLS env var to support building MoltenVK with static Vulkan linkage symbols hidden.
Improve accuracy of VkPhysicalDeviceLimits::timestampPeriod.
Do not use MTLEvent for VkSemaphore under Rosetta2.
On Apple Silicon (iOS, tvOS & macOS), set VkPhysicalDeviceProperties::deviceID from GPU capabilities.
Support compiling MSL 2.4 in runtime pipelines and MoltenVKShaderConverterTool.
Fix issue where MSL 2.3 only available on Apple Silicon, even on macOS.
Fix memory leak of dummy MTLTexture in render subpasses that use no attachments.
Fix Metal object retain-release errors in assignment operators.
Fix use of GPU counter sets on older versions of iOS running on the simulator.
mvk::getShaderOutputs() in SPRIVReflection.h support flattening nested structures.
Replaced ASL logging levels with MVKConfigLogLevel.
MoltenVKShaderConverter tool support loading tessellation shader files.
MoltenVKShaderConverter tool update to MSL 2.4 by default.
Upgrade to Vulkan 1.3 headers.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 33.
Update to latest SPIRV-Cross:
- MSL: Add 64 bit support for OpSwitch.
- MSL: Don't output depth and stencil values with explicit early fragment tests.
- MSL: Fix incorrect MSL gl_TessCoord variable type.
- MSL: Allow copy array from UniformConstant storage.
- MSL: Handle signed atomic min/max.
- Fix normalize on half3/half2.
- MSL: Handle constant construct of block-like array types.
- MSL: Rethink how opaque descriptors are passed to leaf functions.
- Rework how loop iteration counts are validated.
- Clamp vector element access to vector size.
- Handle aliased names in spec constants.
- Add support for LocalSizeId.

MoltenVK 1.1.6

Released 2021/11/15

Set maximum point primitive size based on GPU vendor ID, which can now be as large as 511.
Improved checks for timestamp GPU counter support on older devices.
Fix incorrect validation error on multilayer VkImage marked for rendering, when multilayered-rendering
is not supported on platform, but app doesn't actually attempt to render to multiple layers.
Fix dynamic pipeline state such as vkCmdSetDepthBias() sometimes ignoring pipeline dynamic
state flags when called before vkCmdBindPipeline().
Fix incorrect validation of multilayer-rendering validation when MVKImageView
does not actually perform multilayer-rendering.
Fix issue where dynamic pipeline flags were sometimes read from previously bound pipeline.
Fix issue where correct base layer and mipmap for attachment was sometimes not being used.
Add MTLFence between Metal encoders and timestamp stage counter BLIT encoder
to ensure previous work is finished before being timestamped.
Fix issue with BC1_RGB compressed format where incorrect alpha value returned.
Add vkGetMTLCommandQueueMVK() function to expose underlying MTLCommandQueue object.
Add vkSetWorkgroupSizeMVK() function.
Add unsupported VkApplicationInfo::apiVersion warning.
Update to latest SPIRV-Cross version:
- MSL: Add support for OpSpecConstantOp ops OpQuantizeToF16 and OpSRem.
- MSL: Return fragment function value even when last SPIR-V Op is discard (OpKill).
- MSL: Fix location and component variable matching between shader stages.
- MSL: Fix type redirection when struct members are reordered to align with offsets.
- MSL: Remove over-zealous check for struct packing compatibility.
- MSL: Correctly emit user(clip/cullN) for clip/cull builtins in tess output struct.
- MSL: Don't output depth and stencil values with explicit early fragment tests.
- MSL: Track location component to match vecsize between shader stages.
- MSL: Selectively enable fast-math in MSL code to match Vulkan CTS results.
- MSL: Honor DecorationNoContraction when compiling using fast-math.
- MSL: Honor infinities in OpQuantizeToF16 when compiling using fast-math.
- MSL: Support synthetic functions in function constants.
- MSL: Improve handling of INT_MIN/INT64_MIN literals.
- MSL: Consolidate spvQuantizeToF16() functions into a single template function.
- MSL: Use vec<T, n> in template SpvHalfTypeSelector for function spvQuantizeToF16().
- MSL: Support more usecases for unpacked vectors.
- MSL: Workaround compiler crashes when using threadgroup bool.
- MSL: Handle non-thread storage class in Modf/Frexp pointer versions.
- Improve handling of INT_MIN/INT64_MIN literals.
- Per spec, support undefined behavior for out-of-bounds swizzles.
- Correctly reflect declared buffer size for out of order members.
- Separate (partially) the tracking of depth images from depth compare ops.

MoltenVK 1.1.5

Released 2021/08/30

Changes to how VkSemaphore is supported:
- Revert to prefer MTLEvent for VkSemaphore, except on NVIDIA, where emulation on CPU is preferred.
- Set default value of the MVK_ALLOW_METAL_FENCES environment variable to 0 (false),
Vulkan timestamp query pools use Metal GPU counters when available.
Support resolving attachments with formats that Metal does not natively resolve.
Support stencil-only partial attachment clearing.
Support alpha-to-coverage without a color attachment.
Fix issue where swapchain images were acquired out of order under heavy load.
Fix issue with vkCmdBlitImage() from compressed textures.
Fix incorrect translation of clear color values on Apple Silicon.
Fix swizzle of depth and stencil values into RGBA (float4) variable in shaders.
Fix occasional crash when swizzling used but shader swizzling not enabled.
Fix pipeline barriers not working inside self-dependent subpasses on Apple GPUs.
Fix GPU race condition when clearing a renderpass input attachment on Apple GPUs.
Disable VK_FORMAT_FEATURE_COLOR_ATTACHMENT_BLEND_BIT for
VK_FORMAT_E5B9G9R9_UFLOAT_PACK32 on macOS Apple Silicon.
Fix execution order of encodeBindings for bufferBindings.
Properly ignore non-null pipeline creation pointers that should be ignored.
Add queue and queue family indices to MTLCommandBuffer label.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 32.
Update to latest SPIRV-Cross version:
- MSL: Adjust gl_SampleMaskIn for sample-shading and/or fixed sample mask.
- MSL: Remove redundant path for SampleMask.
- MSL: Fix setting SPIRVCrossDecorationInterpolantComponentExpr decoration.
- MSL: Support row-major transpose when storing matrix from constant RHS matrix.
- MSL: Fix casting in constant expressions with different sizes.
- MSL: Fix duplicate gl_Position outputs when gl_Position defined but unused.
- MSL: Simplify spvSubgroupBallot().
- MSL: Consider that function/private variables can be block-like.
- Track temporary access for OpArrayLength result.

MoltenVK 1.1.4

Released 2021/06/28

Add support for extensions:
- VK_KHR_imageless_framebuffer
Advertise Vulkan extension functions only from enabled extensions.
Make vkGetPastPresentationTimingGOOGLE() queuing behavior compliant with Vulkan spec.
Expose vkGetIOSurfaceMVK() and vkUseIOSurfaceMVK() without requiring Objective-C.
Default MoltenVK build using C++17 and compiler optimization setting -O2.
API fix to remove #include "SPIRVReflection.h" from SPIRVToMSLConverter.h header.
Support Xcode 12.5 build settings, build warnings, and SDK change to availability of
[MTLDevice supportsBCTextureCompression] on Mac Catalyst.
Add support for new AMD devices supporting 32 lanes.
Improve handling of sampler border color and mirror edge clamp.
Improve cache hits when matching SPIRVToMSLConversionConfiguration structs to each other
to find a cached shader, by only considering resources from the current shader stage.
Rename kMVKShaderStageMax to kMVKShaderStageCount.
Fix crash when requesting MTLCommandBuffer logs in runtime debug mode on older OS versions.
Fix synchronization issue with locking MTLArgumentEncoder for Metal Argument Buffers.
Fix race condition on submission fence during device loss.
Fix crash due to incorrect number of attachments when clearing.
Fix crash using memoryless storage for input attachments on Apple Silicon.
Fix issue where M1 GPU does not support reusing Metal visibility buffer offsets
across separate render encoders within a single Metal command buffer (Vulkan submit).
On command buffer submission failure, if MVKConfiguration::resumeLostDevice enabled, do not release
waits on VkDevice, and do not return VK_ERROR_DEVICE_LOST, unless VkPhysicalDevice is also lost.
Fix inconsistent handling of linear attachment decisions on Apple Silicon.
Fix small memory leak during swapchain creation.
Fix stencil clear incorrectly using using the depth loadOp, when stencil is smaller than render area.
Reorganize coherent texture flushing on memory map and unmap`.
Fix issues where data in temporary internal buffers are discarded while in use.
Protect against crash when retrieving MTLTexture when VkImage has no VkDeviceMemory bound.
Adjust some VkPhysicalDeviceLimits values for Vulkan and Metal compliance.
Fix internal reference from SPIRV_CROSS_NAMESPACE_OVERRIDE to SPIRV_CROSS_NAMESPACE.
Add label strings to MTLCommandBuffers, based on use type, for GPU Capture debugging.
Add Scripts/runcts script as a convenience for running Vulkan CTS tests.
Support Xcode 13 SDK APIs and build settings.
Update dependency libraries to match Vulkan SDK 1.2.182.
Update to latest SPIRV-Cross version:
- MSL: Handle array of IO variable with Component decoration.
- MSL: Handle array with component when we cannot rely on user() attrib.
- MSL: Improve handling of split tessellation access chains.
- MSL: Always enable support for base vertex/index on iOS.

MoltenVK 1.1.3

Released 2021/04/27

Add beta support for using Metal argument buffers for shader resources on macOS, by setting
MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS environment variable (disabled by default). This dramatically
expands the number of resources that can be submitted to a pipeline stage, per the Vulkan
VK_EXT_descriptor_indexing extension. Currently available on macOS 11.0 (Big Sur) or later,
and on earlier macOS versions on Intel GPU's.
Add support for HDR10 colorspace via VK_COLOR_SPACE_HDR10_HLG_EXT and VK_COLOR_SPACE_HDR10_ST2084_EXT.
Always explicitly set CAMetalLayer colorspace property based on Vulkan parameters,
and don't rely on Metal default values.
Add MVKConfiguration::resumeLostDevice and MVK_CONFIG_RESUME_LOST_DEVICE env var,
to allow VkDevice to resume after non-fatal VK_ERROR_DEVICE_LOST error.
MVKDescriptorPool pools its descriptor sets.
Enable MVKConfiguration::preallocateDescriptors and MVK_CONFIG_PREALLOCATE_DESCRIPTORS
environment variable by default to preallocate descriptors when a VkDescriptorPool is created.
Avoid use of Metal renderpass load and store actions on memoryless attachments.
Fix memory leak on swapchain destruction.
Fix MVKPhysicalDevice::getSurfaceFormats() returning VK_FORMAT_UNDEFINED.
Fix memory leak where swapchains and images were not destroyed due to a retention loop.
Fix advertising single-texel alignment capability for texel buffers.
Fix time and space inefficiencies caused by missed shader cache lookup hits in MVKShaderLibraryCache.
Log enhanced command buffer errors in debug mode.
Ensure queue submission message logging occurs before submission object is destroyed.
Remove project qualifiers from references to SPIRV-Cross header files.
Only perform automatic GPU capture on queue identified by MVKConfiguration::defaultGPUCaptureScopeQueueIndex
and defaultGPUCaptureScopeQueueFamilyIndex.
Introduce MVKConfigLogLevelBits, MVKConfigAutoGPUCaptureScopeBits, and MVKConfigTraceVulkanCallsBits
enums to specify config API values in a Vulkan-friendly manner, while automatically documenting the same values for env vars.
Add MVKConfiguration::apiVersionToAdvertise and MVK_CONFIG_API_VERSION_TO_ADVERTISE
env var to configure MoltenVK to advertise a particular Vulkan version.
Add MVKConfiguration::advertiseExtensions and MVK_CONFIG_ADVERTISE_EXTENSIONS
env var to configure MoltenVK to force advertising support for no, or minimally few, Vulkan extensions.
Remove the Hologram and API-Samples demo apps, and remove
LunarG/VulkanSamples as a dependency library.
Add NDEBUG macro to all Release builds to remove assert() calls.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 31.
Update dependency libraries to match Vulkan SDK 1.2.176.
Update to latest SPIRV-Cross version:
- MSL: Support long ulong types in buffers in 2.3+.
- MSL: Support padding Metal argument buffer entries based on argument index.
- Add interfaces to aid with LTO-style optimization
- Handle edge cases in OpCopyMemory.

MoltenVK 1.1.2

Released 2021/02/22

Advertise support for shaderInt64 feature.
Support fast math on MSL compiler via MVKConfiguration::fastMathEnabled configuration
setting and MVK_CONFIG_FAST_MATH_ENABLED environment variable (enabled by default).
Support compiling MSL with position invariance if indicated in SPIRV shader.
vkGetMoltenVKConfigurationMVK() and vkSetMoltenVKConfigurationMVK() functions
can now be used with a VkInstance from another Vulkan layer, or with a VK_NULL_HANDLE VkInstance.
MVKConfiguration extended to cover all MoltenVK environment variables.
Report accurate value of 8 for VkPhysicalDeviceLimits::maxBoundDescriptorSets.
Advertise macOS M1 GPU as VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU.
For Vulkan semaphores, prefer using MTLFence over MTLEvent.
Support immmutableSamplers with sampler arrays.
Query pools write to dedicated temporary internal buffer to span multiple render passes
and support larger query counts.
Fixes for race conditions in CTS multithread tests, guarding MTLDevice on cross-thread syncing.
Set Metal buffer alignment to 256 on non-Apple Silicon iOS/tvOS simulators.
MVKMTLBufferAllocation: Support device-local temp buffers for tessellation,
indirect multiview, or occlusion queries buffer usage.
MVKPixelFormats: Enable RenderTarget usage for linear textures on Apple GPUs.
MVKRenderPass: Use a non-trivial granularity for TBDR GPUs.
Don't use barriers in render passes on Apple GPUs.
MVKGraphicsPipeline: Fix color write mask with RGB9E5 RTs.
MVKImagePlane: When sync'ing, create the texture if it doesn't exist.
MVKRenderPass: Don't use Load/Store actions for memoryless.
MVKRenderPass: Only use MTLStorageModeMemoryless where available.
MVKDeviceMemory: Don't consider Memoryless host-accessible on macOS/tvOS.
MVKCmdResolveImage fix incorrectly changing first resolve layer's src/dst base layer.
MVKPhysicalDevice: Require Mac family 2 for render without attachments.
MVKPhysicalDevice: Disable SIMD-group permutation for Mac family 1.
MVKPhysicalDevice: Clamp maximum buffer range to 4 GiB - 1.
MVKMTLBufferAllocation: Mark temp buffers as volatile.
SPIRVReflection: Multiple entry point support for getShaderOutputs().
Remove obsolete MVKVector, which was long ago replaced with MVKSmallVector.
Remove official support for submitting shaders directly containing MSL source code or compiled MSL code.
MSL shaders may still be directly submitted, and may work, but it is not officially supported at this time.
Future versions of MoltenVK may support direct MSL submission again.
Remove ONLY_ACTIVE_ARCH from Debug builds. MoltenVK Debug builds now build for all platform architectures.
Add ability to automatically capture first GPU frame by setting MVKConfiguration::autoGPUCaptureScope
(or environment variable MVK_CONFIG_AUTO_GPU_CAPTURE_SCOPE) to 2.
Support GitHub Actions for CI builds on pull requests.
Support pre-built binary artifacts from GitHub Actions CI builds.
Makefile and fetchDependencies support xcpretty, if available.
Remove support for Travis-CI.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 30.
Update Xcode build settings check to Xcode 12.4.
Support legacy building on Xcode 11.7.
Update dependency libraries to match Vulkan SDK 1.2.170.
Update to latest SPIRV-Cross version:
- MSL: Gracefully assign automatic input locations to builtin attributes.
- MSL: Refactor out location consumption count computation.
- MSL: Always return [[position]] when required.
- MSL: Fix some edge cases in input attachment handling.
- MSL: Fix various bugs with framebuffer fetch on macOS and argument buffers.
- MSL: Always use input_attachment_index for framebuffer fetch binding.
- MSL: Make sure initialized output builtins are considered active.
- MSL: Always enable Outputs in vertex stages.
- MSL: Only consider builtin variables and flatten builtin arrays if they are part of IO interface.
- MSL: Handle load and store to TessLevel array in TESC.
- MSL: Fixup type when using tessellation levels in TESC functions.
- MSL: Fix automatic assign of builtin attributes in tessellation.
- GLSL/MSL: Handle more complicated tessellation Output initializers.
- MSL: Emit correct initializer for tessellation control points.
- MSL: Handle initializers for tess levels.
- MSL: Fix initializer for tess level outputs.
- MSL: Fix broken reserved identifier handling for entry points.
- MSL: Handle reserved identifiers for entry point.
- Fix pathological complexity explosion for certain shaders.
- Improve handling of complex variable initialization.
- Expose position invariance.

MoltenVK 1.1.1

Released 2020/12/09

Add support for extensions:
- VK_KHR_sampler_mirror_clamp_to_edge (iOS)
- VK_KHR_timeline_semaphore
- VK_EXT_descriptor_indexing (initial release limited to Metal Tier 1: 96/128 textures, 16 samplers)
- VK_EXT_post_depth_coverage (macOS)
- VK_EXT_private_data
- VK_EXT_subgroup_size_control
- VK_EXT_texture_compression_astc_hdr
- VK_AMD_shader_image_load_store (macOS)
- VK_IMG_format_pvrtc (macOS)
Support the Mac Catalyst platform for iOS apps on macOS 11.0+,
under both x86_64 and arm64 architectures.
Re-enable MTLEvent-based semaphores and fix several MVKSync issues.
Use VK_KHR_image_format_list to disable MTLTextureUsagePixelFormatView
if only swizzles or sRGB conversion will be used for image views, improving
performance on iOS by allowing Metal to use lossless texture compression.
Handle device loss.
Fix crash in vkUpdateDescriptorSets() when copying inline block descriptors.
Fix Metal validation error when unused elements in an array of sampler are not populated by descriptors.
Fix crashes in vkUseIOSurfaceMVK() on chroma sampling and double releasing ofMTLTexture.
Fix potential drawable present race conditions.
Fix crash in vkUpdateDescriptorSets() when copying inline block descriptors.
Fix Metal validation error when unused elements in an array of sampler are not populated by descriptors.
Move Metal drawable presentation from MTLCommandBuffer to MTLDrawable
to improve performance and reduce blocking.
Allow binding descriptor set using layout different than it was created with.
Report VkPhysicalDeviceLimits::maxPerStageDescriptorStorageImages as Metal limit of 8.
Increase per-stage texture count to 96 for A11 SoC's and above.
Use variable descriptor count when determining descriptor binding count.
Support setting sizes of SPIR-V unsized arrays.
Support MTLStorageTypeMemoryless for Apple Silicon on Mac.
Support Apple GPU pixel formats with Apple Silicon on Mac.
Allow linear images on Apple GPUs in Blit and Clear commands.
Apple family 7 GPUs (A14) on iOS support multisample layered rendering,
as well as sampler border colors and the mirror clamp to edge sampler address mode.
Set fill mode, depth bias, viewport, and scissor states before clearing attachments
Disable culling for the duration of vkCmdClearAttachments()
MVKDevice increase minimum OS for shared-storage textures.
MVKDevice set properties for Apple Silicon GPUs on macOS.
MVKQueue only create one GPUCaptureScope per queue.
MVKSamplerYcbcrConversion always make sure there is one plane.
MVKPhysicalDevice correct fragment input component limit.
MVKPhysicalDevice set max visibility buffer size to 256 kiB where supported.
MVKPhysicalDevice expose support for interpolation functions.
MVKPhysicalDevice enable 3D compressed textures on iOS/tvOS, and forbid ETC2 and EAC
3D textures on all platforms. Apple GPUs do not support 3D for those.
MVKPhysicalDevice enable Apple family 7 features on iOS.
MVKPhysicalDevice remove need to call initGPUInfoProperties() twice.
MVKPhysicalDevice correct max descriptor set resources.
MVKPhysicalDevice reduce maximum point size to 64.
MVKPhysicalDevice enable strictLines for Intel and NVIDIA.
MVKPhysicalDevice enable shaderResourceMinLod on iOS.
MVKPhysicalDevice set correct subgroup properties.
MVKPhysicalDevice enable texture swizzle on all Apple GPUs.
MVKPipelineLayout only set configuration result if validating.
MVKPipeline fix calculation of atomic image buffer addresses.
MVKPipeline disable rasterization if culling both sides and don't try to add a fragment shader.
MVKPipeline shorten vertex attribute format's length when stride < size.
MVKGraphicsPipeline handle minSampleShading.
MVKImage always use texel buffers for linear images in MTLHeaps.
MVKImage make sure plane heap offsets are properly aligned.
MVKImage always set the depth plane when rendering to a 3D image.
MVKImage avoid swizzling storage and/or attachment image views.
MVKImage avoid texel buffer for atomics if view format list
exists and does not include either R32_UINT or R32_SINT format.
MVKImageView always ignore transfer usages.
MVKBufferView avoid triggering bytesPerRow validation warning.
MVKDescriptorSetLayout speed up lookup of descriptor index and streamline binding access.
MVKCmdBlitImage use layered draws when possible.
MVKCmdBlitImage add 0.5 to layer index before interpolating.
MVKCmdBlitImage support depth/stencil blits with inversion and scaling.
MVKSwapchain allow images whose size doesn't match the CAMetalLayer.
MVKPixelFormats add 0.5 ULP to clear values for normalized formats.
MVKCommandEncoder don't set renderTargetArrayLength for mixed 2D/3D renders.
MVKExtensions add missing tvOS case for unsupported extensions.
MVKDescriptorSetLayout sort and hold bindings by binding number.
MVKDescriptor simplify subclass implementations.
MVKComputePipeline override max threads per threadgroup.
MVKGPUCapture make sure the MTLCaptureScope has only one reference.
MoltenShaderConverter fix tvOS build to support tvOS 9.0.
Support building external libraries and dylibs against sanitizers.
Clarify documentation on mapping limitations for host-coherent image memory on macOS.
Add validation policy for MoltenVK development to README.md document.
Update Xcode build settings check to Xcode 12.2.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 29.
Update dependency libraries to match Vulkan SDK 1.2.162.
Update to latest SPIRV-Cross version:
- MSL: Support SPV_EXT_demote_to_helper_invocation for MSL 2.3.
- MSL: Support run-time sized image and sampler arrays
  (GL_EXT_nonuniform_qualifier/SPV_EXT_descriptor_indexing).
- MSL: Support atomic access to images from argument buffers.
- MSL: Add missing interlock handling to atomic image buffers.
- MSL: Fix calculation of atomic image buffer address.
- MSL: Support querying and modifying generated combined sampler suffix.
- MSL: Don't use a bitcast for tessellation levels in tesc shaders.
- MSL: Handle Offset and Grad operands for 1D-as-2D textures.
- MSL: Don't remove periods from swizzle buffer index exprs.
- MSL: Correct definitions of subgroup ballot mask variables.
- MSL: Extract global variables from subgroup ballot operations.
- MSL: Mask ballots passed to ballot bit ops.
- MSL: Don't mask off inactive bits in ballot masks.
- MSL: Support vectors with OpGroupNonUniformAllEqual.
- MSL: Cast broadcast booleans to ushort.
- MSL: Do not use component::x gather for depth2d textures.
- MSL: For 2.1+, don't disable rasterization for vertex writes.
- MSL: Allow post-depth coverage on Mac in MSL 2.3.
- MSL: Allow framebuffer fetch on Mac in MSL 2.3.
- MSL: Allow Bias and Grad arguments with comparison on Mac in MSL 2.3.
- MSL: Support pull-model interpolation on MSL 2.3+
- MSL: Expand subgroup support.
- MSL: Adjust FragCoord for sample-rate shading.
- MSL: Expose some more features on iOS: min_lod_clamp(), simd_is_helper_thread(),
  barycentric_coord, and primitive_id.
- MSL: Don't add fixup hooks for builtin variables if they're unused.
- MSL: Don't try to use [[thread_index_in_simdgroup]] in vertex shaders.
- Handle case where block is loop header, continue AND break block.
- MSL: Added fmin3 and fmax3 library functions to the illegal name list.
- Added Metal keyword: level.
- Parser: Don't assume OpTypePointer will always take a SPIRType.
- Add MIT dual license for the SPIRV-Cross API and CLI.

MoltenVK 1.1.0

Released 2020/09/28

Note: This release contains changes to library paths and framework linking options.

Add support for Vulkan 1.1, including:
- The vkEnumerateInstanceVersion() function
- The vkGetDeviceQueue2() function
- Protected memory (non-functional)
- A feature struct for VK_KHR_shader_draw_parameters
- All extensions that were promoted to core in Vulkan 1.1
Add support for extensions:
- VK_KHR_portability_subset
- VK_KHR_create_renderpass2
- VK_KHR_depth_stencil_resolve
- VK_KHR_external_fence (non-functional groundwork for future extensions,
  including support for GCD and Mach semaphores)
- VK_KHR_external_fence_capabilities (non-functional groundwork for future
  extensions, including support for GCD and Mach semaphores)
- VK_KHR_external_semaphore (non-functional groundwork for future
  MTLSharedEvent Vulkan extension)
- VK_KHR_external_semaphore_capabilities (non-functional groundwork for
  future MTLSharedEvent Vulkan extension)
- VK_KHR_multiview
- VK_KHR_shader_subgroup_extended_types
Remove support for obsolete VK_EXTX_portability_subset extension.
Redesign build and linking options that leverage newer framework technology:
- Add comprehensive support for multi-platform, multi-architecture XCFrameworks.
- Build fat single-platform, multi-architecture dylibs.
- Add support for Apple Silicon builds for macOS and Simulators.
- Remove support for distinct legacy frameworks and static libraries.
- Remove support for fat libraries and frameworks that span device and simulators.
- Combine MoltenVKSPIRVToMSLConverter and MoltenVKGLSLToSPIRVConverter frameworks
  into a single MoltenVKShaderConverter framework.
Support copying between 3D and 2D images.
Support clearing 3D images.
Support linear images and buffer views in shared memory on macOS 10.15.5+.
Support VK_IMAGE_CREATE_EXTENDED_USAGE_BIT.
Support multiple aliased images for dedicated image memory allocations.
Improve performance of tessellation control pipeline stage by processing multiple
patches per workgroup.
vkCmdBindDescriptorSets order pDynamicOffsets by descriptor binding number
within each descriptor set.
vkCmdCopyImage on macOS flush non-coherent image memory before copy operation.
Process multiple patches per workgroup in a tessellation control shader.
Initialize tessellation related variables conditionally in indirect draws.
Fix build errors on Simulator not supporting MTLDrawable present time options.
Fix dynamicOffsets ordering based on binding index.
Ensure the base texture is created when creating a view texture.
Fix features, alignment, and image properties of chroma subsampled formats.
Disable variableMultisampleRate feature.
Permit renderpass to have no attachments.
Clear linear images using a compute shader.
Reject attempts to create compressed linear images.
Always use a texel buffer for atomic linear storage images.
Use deferred store actions instead of tracking multi-pass draws.
Use MTLRenderPassDescriptor renderTargetWidth and renderTargetHeight on macOS 10.15 and newer.
Use a 2D non-arrayed view for 2D non-arrayed attachments.
Use arrayed textures for layered subpass input.
Use layered rendering when clearing or resolving images whenever possible,
and take renderArea into account.
Streamline image copying when the entire source is being copied to the entire destination.
Don't set renderTargetArrayLength on devices that don't support it.
Don't attempt to clear unused attachments and fix vertex count for clearing multiple layers.
Don't encode commands that draw zero vertices.
Ignore addressModeW on samplers with unnormalized coordinates.
Flip GPU when swapchain is created, not when device object is created,
to optimize this condition if it is not needed.
Flush source image of a transfer on macOS.
Fix offset for texel buffers and heaps for multi-planar images.
Fix memory leak when object create fails.
Fix several use-after-freed errors.
Fix applying divisors to instanced vertex attributes.
Fix issue in accessing MTLTexture for swapchain image planes.
Fix occasional crash on vertex stage indirect draws.
Fix reported image format properties for 1D images as 2D.
VK_EXT_vertex_attribute_divisor fix issues with zero divisors.
Re-add support for bitcode generation on iOS and tvOS.
fetchDependencies builds serially by default for better build script integration.
Combine MoltenVKSPIRVToMSLConverter and MoltenVKGLSLToSPIRVConverter
frameworks into a single MoltenVKShaderConverter framework.
Fix Metal validation error when occlusion query and renderpass are in separate
Vulkan command buffers.
Fix a crash on starting a query outside a render pass.
Fix Metal validation error that forbids rendering to an image of zero size.
Fix issue where descriptor pool releasing descriptor sets it doesn't own.
Fix issue where load/store actions not set in renderpass that includes compute stage.
Prevent accidental setColorStoreAction for non-color attachments.
Fix image copy destination extent of compressed images.
Fix image resolve sub-region extent.
Fix owner of merged MVKShaderLibraries.
Fix rounding of buffer sizing when VK_WHOLE_SIZE is used.
Fix detection of indexed draw calls.
vkSetMTLTextureMVK() Fix crash if incoming MTLTexture does not have an associated IOSurface.
Update dependency libraries to match Vulkan SDK 1.2.154.
Update to latest SPIRV-Cross version:
- MSL: Fix handling of matrices and structs in the output control point array.
- MSL: Enclose args when convert distance(a,b) to abs(a-b).
- MSL: Fix multiview view index calculation with a non-zero base instance.
- MSL: Don't set the layer for multiview if the device doesn't support it.
- MSL: Fix OpCompositeInsert and OpVectorInsertDynamic.
- MSL: Support layered input attachments.
- Ensure that we use primary alias type when emitting flattened members.
- Only rewrite type aliases for the base type.
- Overhaul how we deal with reserved identifiers.
- Implement a simple evaluator of specialization constants.
- Deal with case where a selection construct conditionally merges/breaks.
- Allow flip_vert_y in all relevant stages.
- Clean up conditional branch codegen.

MoltenVK 1.0.44

Released 2020/07/28

Add support for extensions:
- VK_KHR_driver_properties
- VK_KHR_sampler_ycbcr_conversion
- VK_EXT_image_robustness
- VK_EXT_robustness2
Add native support for VK_FORMAT_D16_UNORM on iOS 13.0+ and tvOS 13.0+.
Add support for tvOS platform.
Add support for iOS Simulator and tvOS Simulator build destinations.
Cube demo runs on tvOS, iOS Simulator, and tvOS Simulator.
MoltenVK Xcode schemes support building fat Platform+Simulator binaries.
Makefile supports building fat Platform+Simulator binaries, plus Debug builds.
fetchDependencies script supports platform build selection, plus parallel builds.
vkCmdBlitImage() returns error if scaling or inverting to linear image on macOS.
Support VK_FORMAT_A2B10G10R10_UNORM_PACK32 as a surface format.
Support VkPipelineMultisampleStateCreateInfo::pSampleMask.
Support VkPhysicalDeviceSubgroupProperties.
Fix memory layout of inline uniform blocks.
Fix issue where mapped host-coherent device memory not updated from image contents on macOS.
Fix image memory sizing and offsets.
Fix small memory leak when setting swapchain color space.
Fix new and unexpected App Store failure on newly deprecated color space values.
Fix intermittent concurrent shader specialization race condition.
Fix offsets when flushing buffer data to GPU.
Fix issue where expected buffer-sizes buffer not bound to Metal compute encoder.
Ensure fragment shader inputs to have as many components as vertex shader outputs.
Include vertex attribute size when testing whether attribute offset exceeds stride.
Add support for USCALED/SSCALED vertex formats.
Add host-coherent texel buffer caching just for buffer views.
Include MoltenVK Git revision hash in VkPhysicalDeviceProperties::pipelineCacheUUID.
Add MVKPhysicalDeviceMetalFeatures::vertexStrideAlignment to track Metal vertex binding stride alignment.
Add MVKPhysicalDeviceMetalFeatures::indirectTessellationDrawing to track if indirect tessellation drawing is supported.
Remove use of @available() directive as it was causing issues in some build environments.
Pass pipeline sample mask, if present, to SPIRV-Cross.
Refactor MoltenVK Xcode build architectures.
Demo API-Samples generateSPIRVShaders no longer builds MoltenVKShaderController tool.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 27.
Update dependency libraries to match Vulkan SDK 1.2.148.
Update to latest SPIRV-Cross version:
- MSL: Add support for processing more than one patch per workgroup.
- MSL: Workaround broken scalar access chain behavior in MSL LLVM IR / AIR.
- MSL: Do not emit swizzled writes in packing fixups.
- MSL: Ensure OpStore source operands are marked for inclusion in function arguments.
- MSL: Enabling setting an additional fixed sampleMask in fragment shaders.
- MSL: Remove obsolete MSLVertexAttr and MSLShaderInput members.
- MSL: Fix up input variables' vector lengths in all stages.
- MSL: Improve handling of array types in buffer objects.
- MSL: Deal with loading non-value-type arrays.
- MSL: Deal with array load-store in buffer-block structs.
- MSL: Use input attachment index directly for resource index fallback.
- Fix missing switch cases in Y'CbCr conversion.
- Implement context-sensitive expression read tracking.

MoltenVK 1.0.43

Released 2020/06/09

Fix issue in reporting properties of substitutable VkFormats.
Fix vertex attribute offset adjustments when vertex buffer stride is zero.
Update fetchDependencies script to use pre-built spirv-tools files by default.
Update maxVertexInputBindingStride and maxVertexInputAttributeOffset
to minimum Vulkan values.
Numerous documentation typo corrections.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 26.
Update Travis CI to Xcode 11.5.

MoltenVK 1.0.42

Released 2020/06/01

Add support for extensions:
- VK_GOOGLE_display_timing
- VK_KHR_external_memory (non-functional groundwork for future
  Metal-resource Vulkan extension).
- VK_KHR_external_memory_capabilities (non-functional groundwork
  for future Metal-resource Vulkan extension).
Memory consumption improvements in command handling and vector pre-allocation optimizations.
vkQueuePresentKHR() returns a VkResult for each swapchain.
MVKPipeline disable fragment shader outputs for unused attachments.
MVKBuffer support texel buffers in host-coherent memory on Mac.
MVKDescriptor pass buffers to shaders that do atomic image accesses.
Support vertex attribute offsets larger than the vertex buffer stride.
Fix crash when more than two GPUs.
Fix issue where vkGetPhysicalDeviceFormatProperties() incorrectly returned
properties for unsupported formats.
Fix stack overflow in when logging and reporting very long messages.
Fix situation where compute pipeline state not retained across copy and renderpass operations.
Fix buffer offset calculation.
Fixes to maximum FPS calculations.
Fix buffer size passed to shaders when VkDescriptorBufferInfo.range set to VK_WHOLE_SIZE.
Update maximum number of framebuffer layers to 2048.
Support stencil only image formats in identity swizzle case.
Enables format atomic capabilities only when format supports it.
Add MVKSmallVector as a more memory efficient substitute of MVKVector.
Reinstate VulkanSamples API-Samples demo apps and add
input_attachment and push_descriptors demos.
Add MVK_CONFIG_AUTO_GPU_CAPTURE_OUTPUT_FILE environment variable
to support capturing GPU traces to a file.
Consolidate frame and non-frame performance reporting.
- Remove vkGetSwapchainPerformanceMVK() from API.
- Swapchain performance can be retrieved with other activity performance
  through vkGetPerformanceStatisticsMVK().
- Add MVK_CONFIG_PERFORMANCE_LOGGING_INLINE env var to enable/disable
  logging of performance of each activity when it happens.
- Reduce thread locking on performance statistics collection.
Numerous documentation typo corrections.
Support Xcode 11.5.
Update dependency libraries to match Vulkan SDK 1.2.141.
Update to latest SPIRV-Cross version:
- MSL: mark BuiltInFragCoord as implicitly used for subpass reads.
- MSL: Deal with cases where builtin is implicitly needed, declared, but unused.
- MSL: Do not use base expression with PhysicalTypeID OpCompositeExtract.
- MSL: Add options to control emission of fragment outputs.
- MSL: Force disabled fragment builtins to have the right name.
- MSL: Allow removing clip distance user varyings.
- MSL: Support edge case with DX layout in scalar block layout.
- MSL: Deal correctly with initializers on Private variables.
- MSL: Fix case where subpassInput is passed to leaf functions.
- MSL: Redirect member indices when buffer has been sorted by Offset.
- MSL: If the packed type is scalar, don't emit "pack_" prefix.
- MSL: Avoid packed arrays in more cases.
- Do not add NonWritable/NonReadable decorations for regular images.
- Expose a query if samplers or images are comparison resources.

MoltenVK 1.0.41

Released 2020/04/05

Accurately populate Vulkan VkFormatProperties from MTLPixelFormat capabilities,
taking into consideration variations across MTLDevice Features Sets.
Validate format capabilities for MSAA, renderpass attachments, and vkCmdResolveImage().
Fix issue where immutable samplers are removed during descriptor update.
Guard against Metal validation assertion from reuse of query number within a single MTLRenderEncoder.
Increase value of VkPhysicalDeviceLimits::minStorageBufferOffsetAlignment
to 16 to avoid Metal validation assertions.
Add ability to disable command memory pooling using MVK_CONFIG_USE_COMMAND_POOLING
environment variable.
Fix memory leak when pre-filling MTLCommandBuffers using MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS.
Fix issue causing screen captures from swapchain image to deadlock.
Fix memory estimates for iOS 13+.
Broaden conditions for host read sync for image memory barriers on macOS.
Fix issue of reseting CAMetalDrawable and MTLTexture of peer swapchain images.
Fix occasional missing Metal buffer binding when only offset changes.
Fix the make install build command to overwrite the existing framework in the system
framework library, and update README.md to clarify the instructions for using make install.
Update the README.md and MoltenVK_Runtime_UserGuide.md documents to clarify that
MoltenVK is not a fully-compliant implementation of Vulkan.
Support Xcode 11.4.
Disable API-Samples demos and document in Demos/README.md.
Update dependency libraries to match Vulkan SDK 1.2.135.
Update to latest SPIRV-Cross version:
- MSL: Support inline uniform blocks in argument buffers.
- MSL: Move inline uniform blocks to the end of the argument buffer.
- MSL: Fix access chain for deep struct hierarchy on array of buffers.
- MSL: Remove old memory_scope flag from iOS barriers.
- MSL: Fixes to array handling.

MoltenVK 1.0.40

Released 2020/01/22

Refactor descriptor management to reduce memory footprint and fix caching leak.
Add MVK_CONFIG_PREALLOCATE_DESCRIPTORS environment variable to support preallocated
descriptor pooling within a VkDescriptorPool via the VkDescriptorPoolSize values.
Fix crash when app does not use queue family zero.
Fix buffer offset in vkCmdPushDescriptorSet() for non-dedicated buffer memory.
Fix Metal validation error on push constant sizing differences between C and MSL structs.
Use MTLBuffer when inline uniform block descriptor is written to instead of copying host-side bytes.
Fix EXT_inline_uniform_block when using push descriptor sets.
Merge buffer and inline unions to fix issue where binding inline descriptor would interfere with
future binds on the same set index in the same command buffer (now only used in push case anyway).
Track performance of CAMetalLayer nextDrawable call.
Document recommendation to use 3 swapchain images, particularly with full-screen rendering.
Update MoltenVK_Runtime_UserGuide.md to better explain runtime environment variables.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 24.
Update dependency libraries to match Vulkan SDK 1.2.131.
Update to latest SPIRV-Cross version:
- MSL: Support ClipDistance as an input stage variable.
- MSL: Fix automatic binding allocation for image atomic buffers.
- MSL: Deal with packing vectors for vertex input/fragment output.
- MSL: Don't set OrigID when emitting component packed vectors.
- MSL: Add trivial tests for Component decoration.
- MSL: Deal with padded fragment output + Component decoration.
- MSL: Partially implement support for Component decoration in complex scenarios.
- MSL: Explicitly don't support component packing for tessellation.
- MSL: Deal with sign on wave min/max.
- MSL: Add support for force-activating IAB resources.
- Deal with illegal names in types as well.
- Basic implementation of OpCopyLogical.
- Fix sign handling for S/UToF.
- Fix uninitialized memory issue.
- Roll custom versions of isalpha/isalnum.
- Update license headers to year 2020.

MoltenVK 1.0.39

Released 2019/12/16

Add support for extensions:
- VK_EXT_inline_uniform_block
Support linear filtering when using vkCmdBlitImage().
Clamp image copy extents to image extent.
Fix crash in fetchDependencies on build paths containing spaces.
Fix image subresource sizing calculations for heap-based textures.
Fix MTLHeap memory leak in MVKDeviceMemory.
Fix tessellation break when control stage declares but does not use position builtin.
Fix inconsistency in reporting device local memory between type and heap on macOS.
Fix bug where dynamic shader buffers are overflowing.
Avoid reading env vars inside library constructor functions.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 23.
Cube demo use VK_EXT_metal_surface extension.
Support Xcode 11.3.
Update dependency libraries to match Vulkan SDK 1.1.130.
Update to latest SPIRV-Cross version:
- MSL: Rewrite tessellation_access_chain().
- MSL: Report tess input array failures more accurately.
- MSL: Deal with chained access chains for tessellation IO variables.
- MSL: Fix array of array declaration.
- MSL: Declare struct type explicitly.
- MSL: Declare arrays with proper type wrapper.
- MSL: Remove workaround for passing constant arrays to functions.
- MSL: Fix unpacking of column from padded matrix.
- MSL: Fix integer cast.
- MSL: Add missing reference output.
- MSL: Ensure stable output for access chain CFG workarounds.
- MSL: Remove stray allow_id_rewrite().
- MSL: Do read-only lookups of access_chain_children.
- MSL: Do not declare variables which will not be unflattened.
- MSL: Rewrite propagated depth comparison state handling.
- MSL: Do not declare array of UBO/SSBO as spvUnsafeArray<T>.
- MSL: Remove dubious workaround code in unpack_expression().
- MSL: Remove hacky workaround for patch constant passing.
- MSL: Revert hack with kBufferSizeBufferBinding.
- MSL: Remove stale code for texture swizzle.
- MSL: Avoid some fallthrough warnings.
- Expose as public Compiler::update_active_builtins() and has_active_builtin().
- Implement constant empty struct correctly on all backends.
- Mark loop headers as complex as early as possible.
- Clean up call to builtin_translates_to_nonarray().
- Fix broken access tracking for OpFunctionCall results.
- Avoid including stdexcept in no-exception environment.
- Add spvc_type_get_base_type_id().

MoltenVK 1.0.38

Released 2019/10/30

Add support for Metal 3.0 capabilities.
Add support for extensions:
- VK_EXT_swapchain_colorspace (iOS, already supported on macOS).
- VK_EXT_hdr_metadata (macOS)
Use native texture swizzling when available.
Set default value of the MVK_ALLOW_METAL_FENCES environment variable to 1 (true),
to enable use of MTLFence for Vulkan semaphores, by default.
Support additional capabilities in 1D images, including rendering, clearing,
and mipmaps. Add MVK_CONFIG_TEXTURE_1D_AS_2D environment variable to
enable/disable these capabilities.
Use placement MTLHeaps for VkDeviceMemory when possible.
Report heap sizes accurately when possible.
Add support for additional colorspace options.
Add support for the VkPhysicalDeviceFeatures::shaderResourceMinLod feature.
Add support for compressed 3D images on macOS.
Update MoltenVK_Runtime_UserGuide.md about embedding libMoltenVK.dylib in an application.
Clarify static linking as the recommended linking approach for iOS app store distribution.
Add request for feedback from people who reject MoltenVK to README.md document.
Allow MVK_CONFIG_SYNCHRONOUS_QUEUE_SUBMITS build setting to be overridden.
Fix memory leaks of system classes during VkInstance and VkQueue creation.
Fix memory leaks when compiling shaders and pipelines without default OS autorelease pool.
Fix severe FPS degradation caused by certain swapchain recreation situations.
Log format substitution error when MTLPixelFormatDepth24Unorm_Stencil8 is not supported.
Reduce memory usage by adjusting default memory allocs for many MVKVectorInline uses and
replacing use of MVKVectorDefault with std::vector in descriptor set bindings.
Set value of VkPhysicalDeviceLimits::maxTexelBufferElements to more realistic value.
Add linking separate shader texts to GLSLToSPRIVConverter.
Move generation of SPIRV-Cross/mvkSpirvCrossRevisionDerived.h to separate script.
Support Xcode 11.1.
Update dependency libraries to match Vulkan SDK 1.1.126.
Update to latest SPIRV-Cross version:
- MSL: Support option for treating 1D textures as 2D textures of height 1.
- MSL: Fix array copies to/from interpolators.
- MSL: Fix 16-bit integer literals.
- MSL: Fix regression with OpCompositeConstruct from std140 float[].
- Fixes cases where discard and demote are called in pure functions
  and the function result is not consumed.
- Do not consider aliased struct types if the master is not a block.
- Fix OpVectorExtractDynamic with spec constant op index.
- Update SPIR-V headers to SPIR-V 1.5.

MoltenVK 1.0.37

Released 2019/09/10

Add support for extensions:
- VK_KHR_device_group
- VK_EXT_fragment_shader_interlock
Add support for VkEvent, using either native MTLEvent or emulation when MTLEvent not available.
vkInvalidateMappedMemoryRanges() synchronizes managed device memory to CPU.
Track supported instance and device extensions correctly.
Revert to supporting host-coherent memory for linear images on macOS.
Report limit of 64KB for constant buffer bindings on macOS.
Disable depth and/or stencil testing if corresponding attachment is missing.
Ensure Vulkan loader magic number is set every time before returning any dispatchable Vulkan handle.
Fix crash when VkDeviceCreateInfo specifies queue families out of numerical order.
Fix crash in vkDestroyPipelineLayout().
Fix crash when signalling swapchain semaphore using MTLEvent.
Fix crash when determining alignment of invalid pixel formats.
vkCmdBlitImage(): Support format component swizzling.
vkCmdClearImage(): Set error if attempt made to clear 1D image, and fix validation of depth attachment formats.
vkCreateRenderPass(): Return VK_ERROR_FORMAT_NOT_SUPPORTED if format not supported.
vkCmdFillBuffer(): Improve performance 150x by using parallelism more effectively.
Support optional use of MTLFence for Vulkan semaphores via the MVK_ALLOW_METAL_FENCES environment variable.
Remove error logging on VK_TIMEOUT of VkSemaphore and VkFence.
Remove log message warning of obsolescence of vkCreateMacOSSurfaceMVK() and vkCreateIOSSurfaceMVK() functions.
Report error only on the first time a format substitution is made.
Streamline design and use of MVKSemaphore.
Consolidate the various linkable objects into a MVKLinkableMixin template base class.
Use MVKVector whenever possible in MoltenVK, especially within render loop.
No longer prefer dedicated allocations for buffer memory, including buffer-backed images.
Handle the compositeAlpha member of VkSwapchainCreateInfoKHR.
VkPhysicalDevicePortabilitySubsetFeaturesEXTX::events set to true.
Always submit surface presentations using MTLCommandBuffer.
MVKConfiguration::presentWithCommandBuffer is now obsolete.
Don't use MTLCommandBuffer push/popDebugGroup if not available.
MVKSwapchain::signalWhenAvailable() add autoreleasepool around MTLCommandBuffer use.
Add ability to automatically cause an Xcode GPU capture without developer intervention.
Update VK_MVK_MOLTENVK_SPEC_VERSION to version 22.
Update to renaming of VK_INTEL_shader_integer_functions2 enums and structs in latest Vulkan headers.
Update dependency libraries to match Vulkan SDK 1.1.121.
Update to latest SPIRV-Cross version:
- Support the SPV_EXT_fragment_shader_interlock extension.
- MSL: Deal with array copies from and to threadgroup.
- MSL: Deal with Modf/Frexp where output is access chain to scalar.
- MSL: Inline all emitted functions.
- MSL: Inline all non-entry-point functions.
- MSL: Add {Base,}{Vertex,Instance}{,Index} to bitcast_from_builtin_load.
- MSL: Add support for sampler Y'CbCr conversion.
- MSL: Force storage images on iOS to use discrete descriptors.
- MSL: Support dynamic offsets for buffers in argument buffers.
- MSL: Cleanup temporary use with emit_uninitialized_temporary.
- MSL: Unify the get_*_address_space() methods.
- Assume image and sampler can be RelaxedPrecision.
- Fix post-depth coverage for ESSL.
- Fix variable scope when switch block exits multiple times.
- Fix severe performance issue with invariant expression invalidation.
- Fix ParsedIR::mark_used_as_array_length(uint32_t id)
- Deal correctly with sign on bitfield operations.
- Elide branches to continue block when continue block is also a merge.
- Move branchless analysis to CFG.
- Deal with ldexp taking uint input.
- Do not allow base expressions for non-native row-major matrices.
- Do not force temporary unless continue-only for loop dominates.
- Fix ParsedIR::mark_used_as_array_length(uint32_t id).
- Refactor into stronger types in public API.

MoltenVK 1.0.36

Released 2019/07/25

Add support for extensions:
- VK_KHR_device_group_creation
- VK_KHR_swapchain_mutable_format
- VK_KHR_uniform_buffer_standard_layout
- VK_EXT_metal_surface
- VK_EXT_post_depth_coverage
- VK_EXT_scalar_block_layout
- VK_EXT_shader_stencil_export
- VK_EXT_swapchain_colorspace (macOS)
- VK_EXT_texel_buffer_alignment
- VK_AMD_shader_image_load_store_lod
- VK_AMD_shader_trinary_minmax
- VK_INTEL_shader_integer_functions2
Support VK_FORMAT_A2R10G10B10_UNORM_PACK32 as a surface format and view format.
For shaders created directly from MSL, set function name from
VkPipelineShaderStageCreateInfo::pName.
On iOS GPU family 2 and earlier, support immutable depth-compare samplers
as constexpr samplers hardcoded in MSL.
vkCmdCopyImage() support copying between compressed and uncompressed formats
and validate that formats are compatible for copying.
vkCmdBufferImageCopy() fix crash when setting bytes per image in non-arrayed images.
vkCmdBlitImage() supports blit between different texture formats, and multisampled images.
vkCmdResolveImage() supports textures of different sizes.
vkCmdClearImage() returns error if texture is not renderable.
Move push constant binding to vkCmdBindPipeline() from vkCmdBindDescriptorSet().
MVKDeviceMemory keep MTLResourceOptions aligned with MTLStorageMode & MTLCPUCacheMode.
Texture memory requirements don't use shared storage on macOS.
Add MTLCommandBuffer completion timing performance tracking option.
Expand MVK_CONFIG_TRACE_VULKAN_CALLS to optionally log Vulkan call timings.
Skip SPIRV-Tools build in Travis because Travis does not support the required Python 3.
Separate SPIRVToMSLConverterContext into input config and output results.
Use native Metal texture buffers when available.
Fix issue with push constants used across multiple draw calls not being applied.
Fix memory leak in debug marker and debug utils labelling.
Reduce memory leaks when autorelease pools are not available.
Fix pipeline cache lookups.
Fix race condition between swapchain image destruction and presentation completion callback.
Set Metal texture usage to allow texture copy via view.
Fix memory leak in debug marker and debug utils labelling.
Fix issue with push constants used across multiple draw calls not being applied.
Fix crash when binding descriptor set to layout that has been destroyed and recreated.
Return error when MVKImage created as 1D attachment.
Reduce use of autoreleased Obj-C objects, and ensure those remaining are
covered by deliberate autorelease pools.
Document that the functions in vk_mvk_moltenvk.h cannot be used with objects
retrieved through the Vulkan SDK Loader and Layers framework.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 21.
Update dependency libraries to match Vulkan SDK 1.1.114.
Update to latest SPIRV-Cross version:
- MSL: Support SPV_KHR_multiview extension.
- MSL: Support the SPV_KHR_post_depth_coverage extension.
- MSL: Support the SPV_AMD_shader_trinary_minmax extension.
- MSL: Support the SPV_KHR_device_group extension.
- MSL: Support the SPV_INTEL_shader_integer_functions2 extension.
- MSL: Support SubgroupSize / SubgroupInvocationID in fragment.
- MSL: Support OpImageQueryLod.
- MSL: Support MinLod operand.
- MSL: Support PrimitiveID in fragment and barycentrics.
- MSL: Support 64-bit integers.
- MSL: Support OpOuterProduct.
- MSL: Support SubgroupLocalInvocationId and SubgroupSize in all stages.
- MSL: Support scalar reflect and refract.
- MSL: Support scalar block layout.
- MSL: Use the select() function for OpSelect.
- MSL: Handle coherent, volatile, and restrict.
- MSL: Refactor buffer packing logic from ground up.
- MSL: Fix alignment of packed types.
- MSL: Handle packed matrices.
- MSL: Conditionally validate MSL 2.2 shaders.
- MSL: Rewrite how resource indices are fallback-assigned.
- MSL: Support custom bindings for argument buffers.
- MSL: Fix sampling with FP16 coordinates.
- MSL: Deal with scalar input values for distance/length/normalize.
- MSL: Error out on int64_t/uint64_t buffer members as unsupported by Metal.
- MSL: Deal with scalar input values for distance/length/normalize.
- MSL: Re-roll array expressions in initializers.
- MSL: New SDK errors out on cull distance.
- Rewrite how switch block case labels are emitted.
- Fixes to handling of OpPhi and case fallthrough.
- Fix declaration of loop variables with a OpPhi helper copy.
- Handle more cases with FP16 and texture sampling.
- Fix variable scope when an if or else block dominates a variable.
- Fall back to complex loop if non-trivial continue block is found.
- Remove unreasonable assertion for OpTypeImage Sampled parameter.
- Propagate NonUniformEXT to dependent expressions.
- Deal correctly with return sign of bitscan operations.

MoltenVK 1.0.35

Released 2019/06/13

Add support for extensions:
- VK_EXT_debug_report
- VK_EXT_debug_marker
- VK_EXT_debug_utils
- VK_NV_glsl_shader
Support setting workgroup size for shader modules that use
MSL directly instead of converting from SPIR-V.
Tessellation fixes:
- Don't use setVertexBytes() for passing tessellation vertex counts.
- Fix intermediate Metal renderpasses load and store actions maintaining
  attachments appropriately.
- Use empty depth state for tessellation vertex pre-pass.
- Fix tessellated indirect draws using wrong kernels to map parameters.
- Work around potential Metal bug with stage-in indirect buffers.
- Fix zero local threadgroup size in indirect tessellated rendering.
- Fix [[attribute]] assignment for tessellation evaluation shaders.
VkSemaphore optionally uses MTLEvent, if available and
MVK_ALLOW_METAL_EVENTS environment variable is enabled.
Add vkSetWorkgroupSizeMVK() to set compute kernel workgroup size
when using MSL source code or MSL compiled code.
Allow zero count of viewports and scissors.
Report image layer limits for attachments in vkGetPhysicalDeviceImageFormatProperties().
Change log indication of error in logs from [***MoltenVK ERROR***] to
[mvk-error], for consistency with other log level indications.
Allow mvkMTLRenderStagesFromVkPipelineStageFlags() to map to all Vulkan stages,
by indicating whether the pipeline barrier should come before or after the stages.
Automatically update VkPhysicalDeviceProperties::pipelineCacheUUID when SPIRV-Cross revision changes.
Fix crash when clearing attachments using layered rendering on older macOS devices.
Fixes to Metal renderpass layered rendering settings.
vkCmdClearAttachments() returns encoder to previous pipeline, depth-stencil & resource state after execution.
Fix issue clearing stencil attachment via renderpass when depth attachment is not being cleared.
Fix sporadic crash on vkDestroySwapchainKHR().
MoltenVKShaderConverter tool: Add MSL version and platform command-line options.
Fix crash on pipeline cache merge after VkShaderModule destroyed.
Fix case where viewport/scissor doesn't get set properly when mixing dynamic and
static-configured pipelines in the same command buffer.
Fix a race condition between sync objects and queries.
Fix unused attachments terminating loop early.
Fix offset of buffer view relative to buffer offset within device memory.
Guard against missing Metal pipeline states when pipeline compilation fails.
MVKBuffer: Force managed storage for linear textures on shared buffers.
Use device address space when decompressing DXT image data.
Added missing texelBufferTextureWidth setting in MVKComputePipeline::getMTLFunction().
Fixes and consolidation of external library header references.
Allow building external dependency libraries in Debug mode.
Enable AMD and NV GLSL extensions when building glslang for MoltenVKGLSLToSPIRVConverter.
Make external library header references consistent and add MVK_EXCLUDE_SPIRV_TOOLS option.
MVKVector improvements.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 20.
Update to latest SPIRV-Cross version:
- MSL: Add support for subgroup operations.
- MSL: Support argument buffers and image swizzling.
- MSL: Add support for OpArrayLength.
- MSL: Only use constant address space for tessellation control shader.
- MSL: Support native texture_buffer type, throw error on atomics.
- MSL: Add native texture buffer support.
- MSL: Deal with texture swizzle on arrays of images.
- MSL: Fix complex type alias declaration order.
- MSL: Fix declaration of unused input variables.
- MSL: Use correct address space when passing array-of-buffers.
- MSL: Deal correctly with nonuniformEXT qualifier.
- MSL: Cast texture_buffer index to uint.
- MSL: Fix nonuniform test.
- MSL: Fix regression with Private parameter declaration.
- MSL: Support remapping constexpr samplers by set/binding.
- MSL: Support Invariant qualifier on position.
- MSL: Support stencil export.
- Deal with case where a block is somehow emitted in a duplicated fashion.
- Fix infinite loop when OpAtomic* temporaries are used in other blocks.
- Fix tests for device->constant address space change in MSL tessellation control shader generation.
- Accept SPIR-V 1.4 version.

MoltenVK 1.0.34

Released 2019-04-12

Add support for tessellation.
Add correct function entry point handling.
Add support for VK_KHR_get_surface_capabilities2 extension.
Implement newer VK_KHR_swapchain extension functions.
Support the VK_EXT_host_query_reset extension.
Add support for tracking device features enabled during vkCreateDevice().
Handle surface loss due to window moved between screens or a window style change.
Allow zero offset and stride combo in VkVertexInputBindingDescription.
API: Add MVKPhysicalDeviceMetalFeatures::depthSampleCompare.
Fix conditions under which functions return VK_INCOMPLETE.
Fix potential memory leak on synchronous command buffer submission.
Increase shader float constant accuracy beyond 6 digits of precision.
fetchDependencies: Stop on first error.
Clean up behaviour of sparse binding functions.
Fix a possible race condition around MVKMTLBufferAllocation.
Fix memory overrun if no vertex buffer found with same binding as a vertex attribute.
Fix PVRTC texture content loading via memory mapping.
Fix wrong offset for vkCmdFillBuffer() on VK_WHOLE_SIZE.
Fixed crash within MVKPushConstantsCommandEncoderState when accessing absent
graphics pipeline during a compute stage.
Fixed crash when MTLRenderPassDescriptor renderTargetWidth & renderTargetHeight
set on older devices.
Renderpass width/height clamped to the renderArea includes offset, not just extent,
and are set only when layered rendering is supported on device.
Set options properly on a buffer view's MTLTextureDescriptor.
Don't set MTLSamplerDescriptor.compareFunction on devices that don't support it.
Disable the shaderStorageImageArrayDynamicIndexing feature on iOS.
Debug build mode includes dSYM file for each dylib file.
Explicitly build dSYM files in BUILT_PRODUCTS_DIR to avoid conflict between
macOS and iOS build locations.
Makefile supports install target to install MoltenVK.framework.
into /Library/Frameworks/.
Add MVK_CONFIG_TRACE_VULKAN_CALLS env var and build setting to log Vulkan calls made by application.
Log shader performance statistics in any runtime if MVKConfiguration::performanceLoggingFrameCount non-zero.
Suppress visibility warning spam when building Debug macOS from SPIRV-Cross Release build.
Support Xcode 10.2.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 19.
MoltenVKShaderConverter tool:
- Support cs & csh for compute shader file extensions.
- Validate converted MSL with a test compilation.
- Add option to log shader conversion performance.
Update to latest SPIRV-Cross version:
- MSL: Add support for Metal 2 indirect argument buffers.
- MSL: Add support for tessellation control & evaluation shaders.
- MSL: Support VK_KHR_push_descriptor.
- MSL: Force unnamed array builtin attributes to have a name.
- MSL: Set location of builtins based on client input.
- MSL: Ignore duplicate builtin vertex attributes.
- MSL: Fix crash where variable storage buffer pointers are passed down.
- MSL: Fix infinite CAS loop on atomic_compare_exchange_weak_explicit().
- MSL: Fix depth2d 4-component fixup.
- MSL: Expand quad gl_TessCoord to a float3.
- MSL: Fix depth textures which are sampled and compared against.
- MSL: Emit proper name for optimized UBO/SSBO arrays.
- MSL: Support emit two layers of address space.
- MSL: Declare gl_WorkGroupSize constant with [[maybe_unused]].
- MSL: Fix OpLoad of array which is forced to a temporary.
- Add stable C API and ABI.
- Performance improvements & reduce pressure on global allocation.
- Fix case where a struct is loaded which contains a row-major matrix.
- Fix edge case where opaque types can be declared on stack.
- Ensure locale handling is safe for multi-threading.
- Add support for sanitizing address and threads.
- Add support for SPV_NV_ray_tracing.
- Support -1 index in OpVectorShuffle.
- Deal more flexibly with for-loop & while-loop variations.
- Detect invalid DoWhileLoop early.
- Force complex loop in certain rare access chain scenarios.
- Make locale handling threadsafe.
- Support do-while where test is negative.
- Emit loop header variables even for while and dowhile.
- Properly deal with sign-dependent GLSL opcodes.
- Deal with mismatched signs in S/U/F conversion opcodes.
- Rewrite how we deal with locales and decimal point.
- Fix crash when backend.int16_t_literal_suffix set to null.
- Introduce customizable SPIRV-Cross namespaces and use MVK_spirv_cross in MoltenVK.

MoltenVK 1.0.33

Released 2019/02/28

Support the VK_EXT_memory_budget extension.
Support 8-bit part of VK_KHR_shader_float16_int8.
Disable the shaderStorageImageMultisample feature.
Modify README.md to direct developers to Vulkan SDK.
Clarify Xcode version requirements in documentation.
Use the MTLDevice registryID property to locate the GPU in IOKit.
Add GPU device ID for iOS A12 SoC.
Allow logging level to be controlled with MVK_CONFIG_LOG_LEVEL
runtime environment variable.
Allow forcing use of low-power GPU using MVK_CONFIG_FORCE_LOW_POWER_GPU
runtime environment variable.
Set MSL version for shader compiling from Metal feature set.
Don't warn on identity swizzles when fullImageViewSwizzle config setting is enabled.
Track version of spvAux buffer struct in SPIRV-Cross and fail build if different
than version expected by MoltenVK.
Add static and dynamic libraries to MoltenVKShaderConverter project.
Fix crash from use of MTLDevice registryID on early OS versions.
fetchDependencies: Fix issue loading from Vulkan-Portability_repo_revision.
fetchDependencies: Clean MoltenVK build to ensure using latest dependency libs.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 18.
Update to latest dependency libraries to support SDK 1.1.101.
Update to latest SPIRV-Cross version:
- MSL: Implement 8-bit part of VK_KHR_shader_float16_int8.
- MSL: Add a setting to capture vertex shader output to a buffer.
- MSL: Stop passing the aux buffer around.
- Support LUTs in single-function CFGs on Private storage class.

MoltenVK 1.0.32

Released 2019/01/28

Add support for VK_EXTX_portability_subset extension.
iOS: Support dual-source blending with iOS 11.
iOS: Support cube arrays with A11.
iOS: Support layered rendering and multiple viewports with A12.
Use combined store-resolve ops when supported and requested in renderpass.
Fixes to values returned from vkGetPhysicalDeviceImageFormatProperties()
and vkGetPhysicalDeviceImageFormatProperties2KHR().
Log and return VK_ERROR_FEATURE_NOT_PRESENT error if vkCreateImageView()
requires shader swizzling but it is not enabled.
Log and return VK_ERROR_FEATURE_NOT_PRESENT error if array of textures or
array of samplers requested but not supported.
Treat all attributes & resources as used by shader when using pre-converted MSL.
Allow default GPU Capture scope to be assigned to any queue in any queue family.
VkPhysicalDevice: Correct some features and limits.
Stop advertising atomic image support.
vkSetMTLTextureMVK() function retains texture object.
Log to stderr instead of stdout.
fetchDependencies: build spirv-tools when attached via symlink.
Enhancements to MVKVector, and set appropriate inline sizing usages.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 17.
Update to latest SPIRV-Cross version:
- MSL: Use correct size and alignment rules for structs.
- MSL: Fix texture projection with Dref.
- MSL: Deal with resource name aliasing.

MoltenVK 1.0.31

Released 2019/01/17

Support runtime config via runtime environment variables
Add full ImageView swizzling to config, and disable it by default.
Add GPU switching to config, and enable it by default.
Add queue family specialization to config, and disable it by default.
Enable synchronous queue submits as config default.
Support 4 queue families.
Pad fragment shader output to 4 components when needed.
Add support for copying to and from PVRTC images.
Log Vulkan versions in human readable form when reporting version error.
Update VK_MVK_MOLTENVK_SPEC_VERSION to 16.
Advertise the VK_AMD_gpu_shader_half_float extension.
Support the VK_KHR_variable_pointers extension.
MoltenVKShaderConverter tool exit with fail code on any file conversion fail.
Update to latest dependency libraries for Vulkan SDK 1.1.97.
Update to latest SPIRV-Cross version:
- MSL: Support SPV_KHR_variable_pointers.
- MSL: Workaround missing gradient2d() on macOS for typical cascaded shadow mapping.
- MSL: Fix mapping of identity-swizzled components.
- MSL: Support composites inside I/O blocks.
- MSL: Fix case where we pass arrays to functions by value.
- MSL: Add option to pad fragment outputs.
- MSL: Fix passing a sampled image to a function.
- MSL: Support std140 packing rules for float[] and float2[].
- MSL: Fix image load/store for short vectors.
- Performance improvements on iterating internal constructs.
- Update copyright to 2019.

MoltenVK 1.0.30

Released 2018/12/31

Allow 2 or 3 swapchain images to support both double and triple buffering.
Force display to switch to GPU selected by vkCreateDevice() to avoid system
view compositor having to copy from that GPU to display GPU.
Use inline buffer for pipeline auxiliary buffer.
vkCmdCopyImage: Cast source image to the destination format.
Result of vkGetPhysicalDeviceFormatProperties2KHR match vkGetPhysicalDeviceFormatProperties.
MVKImage: Return error for BLOCK_TEXEL_VIEW.
MVKDescriptorSet: Fix handling of immutable samplers.
MVKPipeline: Forbid vertex attribute offsets >= stride.
Fix handling of case where vertex bindings and binding indices don't match up.
Return VK_TIMEOUT even on zero wait if fences not signalled.
Support iOS builds for arm64e architecture.
Improvements to building external libraries.
Print Vulkan semantics when logging converted GLSL.
Support uploading S3TC-compressed 3D images.

MoltenVK 1.0.29

Released 2018/12/15

Replace use of std::vector with MVKVector to support allocations on stack.
Add missing include MVKEnvironment.h to MVKImage.mm for IOSurfaces.
vkCmdClearAttachments apply [[render_target_array_index]] more carefully.
vkCmdPushDescriptorSet: Fix mapping of binding numbers to descriptor layouts.
Forbid depth/stencil formats on anything but 2D images.
MVKCommandPool: Destroy transfer images using the device.
MVKPipeline: Reject non-multiple-of-4 vertex buffer strides.
MVKPipeline: Set auxiliary buffer offsets once, on layout creation.
MVKSampler: Support border colors.
MVKImage: Round up byte alignment to the nearest power of 2.
MVKImage: Don't set MTLTextureUsageRenderTarget for non-blittable formats.
MVKImage: Support image views of 2D multisample array images.
MVKGraphicsPipeline: Add dummy attachments even when rasterization is off.
MVKDeviceMemory: Try creating an MTLBuffer before allocating heap memory.
Add support for VK_FORMAT_A2R10G10B10_UNORM_PACK32.
Support A8B8G8R8_PACK32 formats.
Add new formats and fix existing ones.
On macOS, VK_FORMAT_E5B9G9R9_UFLOAT_PACK32 can only be filtered.
On macOS, linear textures cannot be blitted to.
Depth formats cannot be used for a VkBufferView.
Give every image format we support the BLIT_SRC feature.
Correct supported features of compressed formats.
Correct mapping of packed 16-bit formats.
Add some more vertex formats.
Don't use char/uchar for clearing/copying 8-bit formats.
Explicitly set number of sparse image property/requirement info sets to 0.
Retrieve linear image memory alignment requirements from Metal device.
For each GPU, log MSL version and updated list of feature sets.
Cube demo on iOS support Portrait and Landscape device orientation.
Build the dylib with -fsanitize=address when asan is enabled.
Fix name of generated dSYM file.
Update to latest SPIRV-Cross version:
- MSL don't emit memory_scope after MSL 2.0.

MoltenVK 1.0.28

Released 2018/12/06

Add support for extensions:
- VK_KHR_bind_memory2
- VK_KHR_swapchain_mutable_format
- VK_KHR_shader_float16_int8
- VK_KHR_8bit_storage
- VK_KHR_16bit_storage
- VK_KHR_relaxed_block_layout
- VK_KHR_maintenance3
- VK_KHR_storage_buffer_storage_class
Add support for 2D multisample array textures.
Ignore fragment shader if raster discard is enabled.
Force signedness of shader vertex attributes to match the host.
In debug configurations, create a dSYM bundle for libMoltenVK.dylib.
MVKImage: Take lock when setting the MTLTexture manually.
Optimize MVKFenceSitter.
Support parallel builds of fetchDependencies to improve build times.
Change internal header references to increase header path flexibility.
Update to latest SPIRV-Cross version:
- MSL: Use an enum instead of two mutually exclusive booleans.
- MSL: Force signedness of shader vertex attributes to match the host.
- Support gl_HelperInvocation on GLSL and MSL.

MoltenVK 1.0.27

Released 2018/11/15

Remove destroyed resources from descriptor sets.
Forbid compressed formats on non-2D images.
Update to latest dependency libraries for Vulkan SDK 1.1.92.
Update to latest SPIRV-Cross version:
- MSL: Print early_fragment_tests specifier before fragment shader declaration.
- MSL: Also pack members at unaligned offsets.
- MSL: Also pack 2- and 4- element vectors when necessary.
- MSL: Emit wrapper for SSign (sign() for int types).
- MSL: Support extended arithmetic opcodes.
- Handle opcode OpSourceContinued.
- Handle group decorations.

MoltenVK 1.0.26

Released 2018/11/06

Fix memoryTypes order to match Vulkan spec.
Allow linear images to use host-coherent memory.
Generate Bitcode in iOS libraries.
Allow all pipeline attachements to be unused.
Perform usage checks on 3D images.
Enhancements to dylib generation script.
Update to latest SPIRV-Cross version:
- MSL: Support 8 & 16 bit types.
- MSL: Updated spec constant support.

MoltenVK 1.0.25

Released 2018/10/31

Refactor the build environment.
- Support creation of static library and build framework and dynamic library from it.
- Add Makefile to better support command line or script building integration.
- Update demos to each use one of framework, static library, and dynamic library.
- Refactor and rename the build scripts.
- Refactor and rename the Xcode Schemes.
- Update build and runtime documentation.
Update shader caching for compatibility with texture swizzling.
Support polygonMode VK_POLYGON_MODE_POINT.
vkCreateInstance returns VK_ERROR_INCOMPATIBLE_DRIVER if Metal not available.

MoltenVK 1.0.24

Released 2018/10/16

Support arbitrary swizzles of image data.
Include struct size parameter in VK_MVK_moltenvk extension functions that pass structs that
might change size across extension versions.
Remove vkGetMoltenVKDeviceConfigurationMVK() & vkSetMoltenVKDeviceConfigurationMVK() functions.
Allocate MVKDescriptorSets from a pool within MVKDescriptorPool
Support copying between textures of compatible-sized formats
Support VK_FORMAT_A2B10G10R10_UNORM_PACKED vertex format
Build scripts support SRCROOT path containing spaces.

MoltenVK 1.0.23

Released 2018/09/28

Add support for features:
- shaderStorageImageMultisample
- shaderStorageImageReadWithoutFormat
- shaderStorageImageWriteWithoutFormat
- shaderUniformBufferArrayDynamicIndexing
- shaderSampledImageArrayDynamicIndexing
- shaderStorageBufferArrayDynamicIndexing
- shaderStorageImageArrayDynamicIndexing
Support reduced render area
Support rasterization to missing attachment
Allocate MVKCommandBuffers from a pool within MVKCommandPool.
Update glslang version
Update to latest SPIRV-Cross version:
- MSL: Improve coordinate handling for buffer reads.
- MSL: Expand arrays of buffers passed as input.

MoltenVK 1.0.22

Released 2018/09/25

Add support for extensions:
- VK_KHR_maintenance2
- VK_EXT_vertex_attribute_divisor
- VK_KHR_sampler_mirror_clamp_to_edge
- VK_KHR_image_format_list
- VK_KHR_dedicated_allocation
- VK_KHR_get_memory_requirements2
- VK_EXT_shader_viewport_index_layer
Support multiple viewports and scissor rectangles.
Support sampleRateShading.
Support pre-filling Metal command buffer on same thread as Vulkan command buffer.
Support passing either a CAMetalLayer or an NSView/UIView in the pView member
when creating a surface.
Support views of the stencil aspect of depth/stencil images.
Improvements to subviews on 3D textures.
Enforce single queue per queue family to improve Metal command buffer handling.
Set Metal render target sizes on iOS.
Fix potential deadlocks on query results and fences.
Fix memory leak on SPIRV conversion.
Update to Vulkan header 1.1.85 and latest version of library dependencies.
Update to latest SPIRV-Cross version:
- MSL: Handle the ViewportIndex builtin.
- MSL: Handle the SamplePosition builtin.
- MSL: Fix OpAtomicIIncrement and OpAtomicIDecrement.
- MSL: Support array of arrays composites and copying.
- MSL: Fix issues with casting of builtin integer vectors.

MoltenVK 1.0.21

Released 2018/09/08

Add support for extensions:
- VK_KHR_descriptor_update_template
Create 3D MTLTextureViews for 2D image views of 3D textures.
Allow building and packaging MoltenVK for of only iOS or only macOS.
Move packaging scripts out of Xcode projects and into script files.
vkUpdateDescriptorSet: Handle copies of uninitialized descriptors.
vkCmdFillBuffer & vkCmdCopyBuffers: Use dispatch call that supports older OS versions.
Update to latest SPIRV-Cross version:
- MSL: Emit F{Min,Max,Clamp} as fast:: and N{Min,Max,Clamp} as precise
- MSL: Implement multisampled array textures.
- MSL: Emit spvTexelBufferCoord() on ImageWrite to a Buffer.
- MSL: Handle interpolation qualifiers.
- MSL: Account for components when assigning locations to varyings.
- MSL: Do not emit function constants for version < 1.2.

MoltenVK 1.0.20

Released 2018/09/01

Add support for extensions:
- VK_KHR_maintenance1
- VK_KHR_shader_draw_parameters
- VK_KHR_get_physical_device_properties2
- VK_KHR_push_descriptor
Add ability to track and access supported and enabled extensions.
Update to latest SPIRV-Cross version.

MoltenVK 1.0.19

Released 2018/08/23

Move MoltenVK config to instance instead of device.
Add MVKConfiguration and deprecate MVKDeviceConfiguration.
Add vkGetMoltenVKConfigurationMVK() and deprecate vkGetMoltenVKDeviceConfigurationMVK().
Add vkSetMoltenVKConfigurationMVK() and deprecate vkSetMoltenVKDeviceConfigurationMVK().
Add build setting overrides for all initial MVKConfiguration member values.
Support Xcode 10: Explicitly specify MoltenVKSPIRVToMSLConverter as prelink library.
Update to Vulkan header 1.1.83 and latest version of library dependencies.

MoltenVK 1.0.18

Released 2018/08/15

vkCmdFullBuffer() fills buffer using compute shader.
Fix API for updating MVKDeviceConfiguration::synchronousQueueSubmits.
vkGetPhysicalDeviceFormatProperties() return VK_FORMAT_FEATURE_VERTEX_BUFFER_BIT
if supported, even if other format properties are not.
Support Metal GPU capture scopes.
Update to latest SPIRV-Cross, glslang & SPIRV-Tools.

MoltenVK 1.0.17

Released 2018/07/31

Disable rasterization and return void from vertex shaders that write to resources.
Add SPIRVToMSLConversionOptions::isRasterizationDisabled to allow pipeline and
vertex shader to communicate rasterization status.
Track layered rendering capability.
Add MVKPhysicalDeviceMetalFeatures::layeredRendering.
Add mvkStaticCmdShaderSource() to generate static MSL shader source for commands.
Add MVKDevice::getMTLCompileOptions() to consolidate shader compilation options.
CreatePipelines return error when fragment MSL translation fails.
Add new vertex format VK_FORMAT_A2B10G10R10_SNORM_PACK32.
Fix watermark timing.
Update MoltenVK spec version to 6.
Remove obsolete deprecated licensing functions.
Rename folders and project for Cube demo.
Update What's New document for earlier releases.
Update to latest library dependencies.
Update to latest SPIRV-Cross version.

MoltenVK 1.0.16

Released 2018/07/24

Fixes to attachment and image clearing to pass CTS tests.
MVKCmdClearAttachments support clearing multiple attachment layers.
MVKCmdClearImage use renderpass clear, and support clearning multiple image layers.
Rename mvkCmdClearImage() to mvkCmdClearColorImage().
MVKDevice add getFormatIsSupported() to allow devices to test for format support.
MVKFramebuffer support multiple layers.
mvk_datatypes.h support both 2D and 3D mipmap calculations and allow
mvkMTLPrimitiveTopologyClassFromVkPrimitiveTopology() in iOS.
Remove support for VK_FORMAT_B10G11R11_UFLOAT_PACK32 & VK_FORMAT_E5B9G9R9_UFLOAT_PACK32
since format components are reversed on Metal.
Report correct workgroup sizes from MTLDevice.
Retrieve VkPhysicalDeviceLimits::maxComputeWorkGroupSize &
maxComputeWorkGroupInvocations & maxComputeSharedMemorySize from MTLDevice.
Move OS extension source files to new OS directory.
Update to latest SPIRV-Cross version.

MoltenVK 1.0.15

Released 2018/07/12

Link IOSurface on iOS only if IPHONEOS_DEPLOYMENT_TARGET is at least iOS 11.0.
Update to latest SPIRV-Cross.

MoltenVK 1.0.14

Released 2018/07/04

vkGetPhysicalDeviceImageFormatProperties() indicate 1D texture limitations.
Fix compute shader workgroup size specialization.
Support separate specialization for each workgroup dimension.
Support zero as a specialization ID value.
Set correct value for VkPhysicalDeviceLimits::maxPerStageDescriptorInputAttachments.
Cleanup MoltenVKShaderConverterTool.
Update to latest SPIRV-Cross.

MoltenVK 1.0.13

Released 2018/06/28

Support larger VkBufferViews by using 2D Metal textures.
Swapchain return VK_ERROR_OUT_OF_DATE_KHR when window resized.
Improve crispness of visuals on macOS Retina displays.
Set CAMetalLayer magnificationFilter property to Nearest by default.
Add MVKDeviceConfiguration::swapchainMagFilterUseNearest member to allow overrides.
Update to latest SPIRV-Cross.

MoltenVK 1.0.12

Released 2018/06/22

Sorting Metal devices in the list of physicalDevices by whether they are headless.
vkCmdBlitImage() support texture arrays as source and destination targets.
vkCmdBlitImage() remove broken support for depth/stencil scaling.
vkCmdClearImage() fixes to clearing depth and stencil formats and avoid Metal validation errors.
Fix slice index when rendering to cube maps.
Fix texture file copy in Cube Demo.
fetchDeps: Add flags for pre-built repos.
Update to latest library dependencies to match Vulkan SDK 1.1.77.
Update to latest SPIRV-Cross.

MoltenVK 1.0.11

Released 2018/06/12

Avoid fragment shader tracking interacting with vertex attributes.
Restrict allowed linear tiling features for pixel formats.
Fix bad logic when testing allowed linear tiling usage.
Fix copying 4-byte 32-bit depth/stencil formats between buffers and textures.
Fix MSL compilation failures on macOS 10.14 Mojave Beta.
Update to latest SPIRV-Cross.

MoltenVK 1.0.10

Released 2018/06/05

Support mapping and filling device memory before binding an image to it.
Fix vsync not being enabled in IMMEDIATE present mode. MVK_MACOS was not being defined.
Avoid Metal validation error on MTLBuffer.contents access from private storage.
Support using Metal texel buffer for linear images to increase host coherency.
MVKDeviceMemory track MVKImages and MVKBuffers separately.
Per Vulkan spec, restrict linear images to 2D, non-array, single mipmap.
Use texel buffer if possible for texture on coherent device memory.
Only flush MVKImages (not MVKBuffers) when device memory mapped.
Do not flush texel buffer images.
Replace dependency on Vulkan-LoaderAndValidationLayers with Vulkan-Headers and Vulkan-Tools.
Update to latest SPIRV-Cross.

MoltenVK 1.0.9

Released 2018/05/23

Fix an issue where the depth format in MVKCmdClearImage was not getting set correctly.
Move surface access to UI components to main thread.
Fix deadlock possibility between MVKFence and MVKFenceSitter.
Fix handling of locking on deferred-destruction objects.
vkGetPhysicalDeviceImageFormatProperties returns VK_ERROR_FORMAT_NOT_SUPPORTED
if the format is not supported.
Default value of MVKDeviceConfiguration::metalCompileTimeout set to infinite.
Update to latest SPIRV-Cross.

MoltenVK 1.0.8

Released 2018/05/18

Allow queue processing to be optionally handled on the submitting (render) thread.
Update to latest SPIRV-Cross.

MoltenVK 1.0.7

Released 2018/05/14

Cache MTLCommandQueues for reuse to handle long delays in creating new VkDevices and VkQueues.
Handle multiple MVKResources mapped to the same region of a single MVKDeviceMemory.
Add Metal library, function and pipeline compilation timeout limits.
Create copies of MVKShaderLibraries when merging pipeline caches.
Handle NULLs when freeing command buffers.
Replace delete with call to destroy() for all MVK objects.
Handle null pointers in vkDestroy...() functions.
Set default value of MVKDeviceConfiguration::supportLargeQueryPools to true by default.
Fixes to run Vulkan CTS without crashes.
Remove mutex locks on MVKDescriptorPool.
Update to latest SPIRV-Cross.

MoltenVK 1.0.5

Released 2018/05/04

Add features to support Vulkan CTS.
Dynamically create frag shaders for clearning attachments and images.
Dynamically create frag shaders for blitting scaled images.
MVKGraphicsPipeline don't create MTLRenderPipelineState if vertex function conversion fails.
MVKComputePipeline don't create MTLComputePipelineState if compute function conversion fails.
Handle SPIRV-Cross errors thrown during SPIR-V parsing in compiler construction.
Set undefined property limits to large, but not max, values to avoid casting issues in app.
Mark multiDrawIndirect features as available.
Support VK_FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT.
Separate categories from MVKOSExtensions.
Update to latest SPIRV-Cross.

MoltenVK 1.0.4

Released 2018/04/22

Support depth clip mode only from MTLFeatureSet_iOS_GPUFamily2_v4 onwards.
MVKCmdClearAttachments & MVKCmdClearImage support multisampled attachments and images.
Don't use CAMetalLayer displaySyncEnabled property if it is not available.
Update python brew install command.
Update to latest SPIRV-Cross.

MoltenVK 1.0.3

Released 2018/04/18

Add support for VK_PRESENT_MODE_IMMEDIATE_KHR swapchain presentation mode.
Round up row and layer byte counts when copying compressed images with sizes
that are not integer multiples of block size.
Queue and device wait idle handled by internal fence instead of semaphore.
vkCmdCopyBufferToImage() & vkCmdCopyImageToBuffer() support a VkBuffer
that is bound to an offseted position in a VkDeviceMemory.
MVKImage::getArrayLayers() reports only layer count and excludes depth.
Add workaround for apps that use one semaphore for all swapchain images.
Support deferred secondary signaling of semaphore & fence acquired while image is free.
Update to latest cube.c version.
Use ninja if available to build dependencies.
Build the demos in Travis-CI.
Update to latest V-LVL, glslang & SPIRV-Tools.
Update to latest SPIRV-Cross.

MoltenVK 1.0.2

Released 2018/04/02

Add support for caching converted MSL shader code offline from pipeline cache
via vkGetPipelineCacheData(), vkCreatePipelineCache() & vkMergePipelineCaches().
Present using command buffer by default.
Support SPIR-V containing multiple entry points.
Add option for per-frame performance logging via un-commentable logging code.
VkPhysicalDeviceProperties::pipelineCacheUUID value derived from MoltenVK
version and highest supported Metal feature set.
vkCmdClearAttachments() don't attempt to clear non-existing depth & stencil attachments.
Always clamp scissors to render area to avoid Metal validation error.
Move fetchDependencies to top directory.
Turn caching of Externals off in .travis.yml.
Add instructions in README.md about building MoltenVK via the command line.
Update to latest SPIRV-Cross.

MoltenVK 1.0.1

Released 2018/03/19

Add support for Vulkan Loader and Validation Layer API version 5.
Add support for LunarG Vulkan Loader ICD API.
Add Vulkan Loader and Validation Layer ICD JSON file.
Fix vkGetInstanceProcAddr to work with 1.1 loader.
Use fetchDependencies script instead of submodules.
Align versioning of external libraries with those used by LunarG SDK.
Combine multiple VkCommandBuffers into a single MTLCommandBuffer.
On command buffer submission, defer waiting on semaphores until just before
MTLCommandBuffer is committed.
Retrieve heap size from MTLDevice on macOS and from free shared system memory on iOS.
Allow color attachment on depth-only rendering.
Allow color attachment when clearing depth only.
Support DXT1 RGB texture compression.
Support VK_FORMAT_FEATURE_VERTEX_BUFFER_BIT on VkFormats that are not supported
as texture formats under Metal.
Don't check if texture is coherent on macOS, since it never is.
Setup push constants for compute shaders.
Check if storage mode is not shared when checking if synchronize is needed.
Log which GPU is attached to a VkDevice.
Sort multiple GPU's to put higher-power GPU's at front of list.
Populate VkPhysicalDeviceProperties vendorID, deviceID and pipelineCacheUUID.
Ensure scissors fit inside renderpass area to avoid Metal validation assertions.
Consolidate setting of viewport and scissors by pipeline and command.
Make MVKBuffer::getMTLBuffer() thread-safe.
Fix Metal validation error with a renderpass with no depth attachment.
Use pipelineStatisticsQuery feature to determine whether pipeline stats are available.
Modify MVKImageView to fix MTLTexture used for renderpasses.
Fix vkBindImageMemory crash when multiple simultaneous threads are binding to
different offsets in the of the same VkDeviceMemory.
Don't align push constant buffer.
Fix vkCmdCopyBuffer when copying unaligned regions.
Added workgroup size specialization constants
Fix SPIRV-Cross OOM conditions with multiple consecutive two-vector OpVectorShuffles.
Support non-square row-major matrix conversions.
Fix vkCmdBlitImage between images of different sizes.
Add ability to write SPIR-V to file for debugging purposes.
Update ThirdPartyConfig.md to latest use of SPIRV-Cross testability.
Fixes to compute workgroup sizes and barriers.
Improved extraction of entry point name and workgroup size from SPIR-V.
Consolidate to a single ThirdPartyConfig.md document.
MSL enhancements to nested function use of globals.
Support customizing MSL based on iOS or macOS platform.
MSL threadgroup barrier memory scope only on iOS MSL 2.0.
MVKBufferView add lock when creating MTLTexture.
MVKDeviceMemory add lock when creating MTLBuffer during memory mapping.
MVKMTLBufferAllocator does not need to be threadsafe.
Cleanup syntax on other lock handling to add consistency.
Consolidate timestamps and performance tracking.
Derive vkCmdCopyBuffer() alignment requirement at runtime.
Don't log error from vkGetPhysicalDeviceFormatProperties() if format not supported.
Add printf-like macros to MVKLogImpl and mvkNotifyErrorWithText.
Updates to dylib building process. Use clang instead of libtool.
Allow MoltenVK to be installed and built without asciidoctor.
Add CI support using Travis CI.
Automatically install demo apps.
Cube demo generate SPIR-V as part of demo project build.
Disable watermark in debug builds.
Add build and runtime OS and device requirements to documentation.
Add Compliance and Contribution sections to README.md.
Remove executable permissions from non-executable files.
Update to latest SPIRV-Cross.

MoltenVK 1.0.0

Released 2018/02/26

Initial open-source release!

File: ExternalRevisions/README.md

#MoltenVK External Dependencies

Fetching and Building External Libraries
Updating External Library Versions
Adding the cereal Library to the MoltenVK Xcode Project
Adding the SPIRV-Tools Library to the ExternalDependencies Xcode Project
Adding the SPIRV-Cross Library to the ExternalDependencies Xcode Project

Fetching and Building External Libraries

MoltenVK uses technology from the following external open-source libraries:

These external open-source libraries are maintained in the External directory.
To retrieve and build these libraries from their sources, run the fetchDependencies
script in the main repository directory:

text

./fetchDependencies --all [--debug]

The --debug option will build the external libraries in Debug mode, which may
be useful when debugging and tracing calls into those libraries.

Updating External Library Versions

To maintain consistency between the libraries, MoltenVK retrieves specific
versions of each external library. The version of each external library is
determined as follows:

cereal: a GitHub repository commit identifier found in the
ExternalRevisions/cereal_repo_revision file.
SPIRV-Cross: a GitHub repository commit identifier found in the
ExternalRevisions/SPIRV-Cross_repo_revision file.
SPIRV-Headers: a GitHub repository commit identifier found
in the ExternalRevisions/SPIRV-Headers_repo_revision file.
SPIRV-Tools: a GitHub repository commit identifier found
in the ExternalRevisions/_SPIRV-Tools__repo_revision file.
volk: a GitHub repository commit identifier found in the
ExternalRevisions/Volk_repo_revision file.
Vulkan-Headers: a GitHub repository commit identifier found in the
ExternalRevisions/Vulkan-Headers_repo_revision file.
Vulkan-Tools: a GitHub repository commit identifier found in the
ExternalRevisions/Vulkan-Tools_repo_revision file.

You can update which versions of the external libraries are retrieved by changing
the value held in the corresponding *_repo_revision file listed above.

Once you have made changes to the *_repo_revision files, you can retrieve the updated
library versions by running the fetchDependencies script, as described above, again.

Note: If, after updating to new versions of the external libraries, you encounter
build errors when building MoltenVK, review the instructions in the sections below
to ensure all necessary external library files are included in the MoltenVK builds.

Note: Vulkan-Tools and volk are not used by MoltenVK itself, but are used
by the Cube demo app included in the MoltenVK repository.

Adding the cereal Library to the MoltenVK Xcode Project

The MoltenVK Xcode project is already configured to use the cereal library. However, after
updating the version of cereal, as described above, if you encounter any building
errors, you may need to re-add the cereal library to the MoltenVK Xcode project as follows:

In the Project Navigator panel, select the MoltenVK Xcode project, then the MoltenVK
project target, and open the Build Settings tab. Locate the build setting entry
Header Search Paths (HEADER_SEARCH_PATHS) and add the following paths:
text
```
"$(SRCROOT)/../External/cereal/include"
```

Adding the SPIRV-Tools Library to the ExternalDependencies Xcode Project

The ExternalDependencies Xcode project is already configured to use the SPIRV-Tools
library. However, after updating the version of SPIRV-Tools, as described above,
if you encounter any building errors, you may need to re-add the SPIRV-Tools library to the
ExternalDependencies Xcode project as follows:

In the Project Navigator panel, select the ExternalDependencies Xcode project, then
select the SPIRV-Tools-macOS target, and open the Build Settings tab. Locate the build
setting entry Header Search Paths (HEADER_SEARCH_PATHS) and add the following paths:
text
```
$(inherited) 
 "$(SRCROOT)/External/SPIRV-Tools/" 
 "$(SRCROOT)/External/SPIRV-Tools/include" 
 "$(SRCROOT)/External/SPIRV-Tools/external/spirv-headers/include" 
 "$(SRCROOT)/External/SPIRV-Tools/build"
```
Repeat Step 1 for the SPIRV-Tools-iOS, SPIRV-Tools-tvOS, and SPIRV-Tools-xrOS targets within theExternalDependencies` Xcode project
In the Project Navigator, remove the Group named source from under the Group named
External/SPIRV-Tools.
Drag the External/SPIRV-Tools/source file folder to the External/SPIRV-Tools
group in the Project Navigator panel. In the Choose options for adding these files dialog
that opens, select the Create groups option, add the files to all of the SPIRV-Tools-macOS,
SPIRV-Tools-iOS, SPIRV-Tools-tvOS, and SPIRV-Tools-xrOS targets, and click the Finish button.
Remove the following Groups from under the Group named External/SPIRV-Tools/source:
- fuzz
- wasm
To avoid compilation warnings, remove the following Files
from under the Group named External/SPIRV-Tools/source:
- mimalloc.cpp
- pch_source.cpp
- opt/pch_source_opt.cpp
- reduce/pch_source_reduce.cpp
- util/timer.cpp
In the Scripts folder, run ./packagePregenSpirvToolsHeaders, which will fetch and
build the full SPIRV-Tools library and will update Templates/spirv-tools/build.zip
from the *.h and *.inc files in External/SPIRV-Tools/build.
Test by running ./fetchDependencies --all and a MoltenVK build.

Adding the SPIRV-Cross Library to the ExternalDependencies Xcode Project

The ExternalDependencies Xcode project is already configured to use the SPIRV-Cross
library. However, after updating the version of SPIRV-Cross, as described above,
if you encounter any building errors, you may need to re-add the SPIRV-Cross library to the
ExternalDependencies Xcode project as follows:

In the Project Navigator, remove all of the files under the Group named
External/SPIRV-Cross.

Drag the following files from the External/SPIRV-Cross directory to the External/SPIRV-Cross
group in the Project Navigator panel:

text

spirv_cfg.cpp
 spirv_cfg.hpp
 spirv_common.hpp
 spirv_cross_containers.hpp
 spirv_cross_error_handling.hpp
 spirv_cross_parsed_ir.cpp
 spirv_cross_parsed_ir.hpp
 spirv_cross_util.hpp
 spirv_cross.cpp
 spirv_cross.hpp
 spirv_glsl.cpp
 spirv_glsl.hpp
 spirv_msl.cpp
 spirv_msl.hpp
 spirv_parser.cpp
 spirv_parser.hpp
 spirv_reflect.cpp
 spirv_reflect.hpp
 spirv.hpp

In the Choose options for adding these files dialog that opens, select the Create groups option,
add the files to all of the SPIRV-Cross-macOS, SPIRV-Cross-iOS, and SPIRV-Cross-tvOS targets,
and click the Finish button.

Regression Testing Your Changes to SPIRV-Cross

The SPIRV-Cross library plays an important part in providing features for MoltenVK, and if
you are developing features for MoltenVK, you may end up making changes to SPIRV-Cross.

If you make changes to the SPIRV-Cross repository, you can build a new version of the libSPIRVCross.a
static library by opening the ExternalDependencies.xcodeproj Xcode project, and running the
ExternalDependencies Xcode scheme. You can then rebuild MoltenVK to include the new library.

While makng changes to the SPIRV-Cross repository, you can regression test your changes using the
following steps:

text

cd External/SPIRV-Cross
	./checkout_glslang_spirv_tools.sh
	./build_glslang_spirv_tools.sh
	./test_shaders.sh

File: README.md Copy Chapter

MoltenVK

Table of Contents Copy Chapter

Introduction to MoltenVK Copy Chapter

Developing *Vulkan* Applications for *macOS, iOS, tvOS, and visionOS* Copy Chapter

Using the *Vulkan SDK* Copy Section

Using MoltenVK Directly Copy Section

Fetching **MoltenVK** Source Code Copy Chapter

Building **MoltenVK** Copy Chapter

Building With _Xcode_ Copy Section

Building From the Command Line Copy Section

Hiding _Vulkan_ API Symbols Copy Section

Accessing _Metal_ Private API Calls Copy Section

Install **MoltenVK** to Replace the _Vulkan SDK_ `libMoltenVK.dylib` Copy Section

Running **MoltenVK** Demo Applications Copy Chapter

Using **MoltenVK** in Your Application Copy Chapter

**MoltenVK** and *Vulkan* Compliance Copy Chapter

Getting Support Copy Chapter

Contributing to **MoltenVK** Development Copy Chapter

Licensing Copy Section

*Vulkan* Validation Copy Section

Memory Management Copy Section

Code Formatting Copy Section

File: Demos/README.md Copy Chapter

Table of Contents Copy Chapter

*Cube* Copy Chapter

*Khronos Vulkan Samples* Copy Chapter

File: Docs/MoltenVK_Configuration_Parameters.md Copy Chapter

MoltenVK Configuration Parameters

MVK_CONFIG_ACTIVITY_PERFORMANCE_LOGGING_STYLE

Type: Enumeration

Default: `0`

MVK_CONFIG_ADVERTISE_EXTENSIONS

Type: UInt32

Default: `1`

MVK_CONFIG_API_VERSION_TO_ADVERTISE

Type: UInt32

Default: `4210688` (decimal number for `VK_API_VERSION_1_4`)

MVK_CONFIG_AUTO_GPU_CAPTURE_OUTPUT_FILE

Type: String

Default: `""`

MVK_CONFIG_AUTO_GPU_CAPTURE_SCOPE

Type: Enumeration

Default: `0`

MVK_CONFIG_DEBUG

Type: Boolean

Default: `0`

MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_FAMILY_INDEX

Type: UInt32

Default: `0`

MVK_CONFIG_DEFAULT_GPU_CAPTURE_SCOPE_QUEUE_INDEX

Type: UInt32

Default: `0`

MVK_CONFIG_DISPLAY_WATERMARK

Type: Boolean

Default: `0`

MVK_CONFIG_FAST_MATH_ENABLED

Type: Enumeration

Default: `2`

MVK_CONFIG_FORCE_LOW_POWER_GPU

Type: Boolean

Default: `0`

MVK_CONFIG_LOG_LEVEL

Type: Enumeration

Default: `3`

MVK_CONFIG_MAX_ACTIVE_METAL_COMMAND_BUFFERS_PER_QUEUE

Type: UInt32

Default: `64`

MVK_CONFIG_METAL_COMPILE_TIMEOUT

Type: UInt64

Default: `INT64_MAX`

MVK_CONFIG_PERFORMANCE_LOGGING_FRAME_COUNT

Type: UInt32

Default: `0`

MVK_CONFIG_PERFORMANCE_TRACKING

Type: Boolean

Default: `0`

MVK_CONFIG_PREFILL_METAL_COMMAND_BUFFERS

Type: Enumeration

Default: `0`

File: README.md

Table of Contents

Introduction to MoltenVK

Developing Vulkan Applications for macOS, iOS, tvOS, and visionOS

Using the Vulkan SDK

Using MoltenVK Directly

Fetching MoltenVK Source Code

Building MoltenVK

Building With _Xcode_

Building From the Command Line

Hiding _Vulkan_ API Symbols

Accessing _Metal_ Private API Calls

Install MoltenVK to Replace the _Vulkan SDK_ `libMoltenVK.dylib`

Running MoltenVK Demo Applications

Using MoltenVK in Your Application

MoltenVK and Vulkan Compliance

Getting Support

Contributing to MoltenVK Development

Licensing

Vulkan Validation

Memory Management

Code Formatting

File: Demos/README.md

Table of Contents

Cube

Khronos Vulkan Samples

File: Docs/MoltenVK_Configuration_Parameters.md

File: Docs/MoltenVK_Runtime_UserGuide.md

Table of Contents

About This Document

About MoltenVK

Installing MoltenVK in Your Vulkan Application

Install MoltenVK as a Universal `XCFramework`

Install MoltenVK as a Dynamic Library on _macOS_

Optionally Link to Required System Libraries

Build and Runtime Requirements

Interacting with the MoltenVK Runtime

MoltenVK Header Files