vkd3d-proton is a fork of VKD3D, which aims to implement the full Direct3D 12 API on top of Vulkan. The project serves as the development effort for Direct3D 12 support in Proton.

The original project is available at WineHQ.

Performance and game compatibility are important targets, at the expense of compatibility with older drivers and systems. Modern Vulkan extensions and features are aggressively made use of to improve game performance and compatibility. It is recommended to use the very latest drivers you can get your hands on for the best experience. Backwards compatibility with the vkd3d standalone API is not a goal of this project.

There are some hard requirements on drivers to be able to implement D3D12 in a reasonably performant way.

• Vulkan 1.3
• Descriptor indexing with at least 1000000 UpdateAfterBind descriptors for all types except UniformBuffer. Essentially all features in VkPhysicalDeviceDescriptorIndexingFeatures must be supported.
• Further, the following device features are required:
  • samplerMirrorClampToEdge
  • shaderDrawParameters
• VK_EXT_robustness2
• VK_KHR_push_descriptor

Some notable extensions that should be supported for optimal or correct behavior. These extensions will likely become mandatory later.

• VK_EXT_image_view_min_lod

VK_EXT_mutable_descriptor_type (or the vendor VALVE alias) and VK_EXT_descriptor_buffer are also highly recommended, but not mandatory.

For AMD, RADV is the recommended driver and the one that sees most testing on AMD GPUs. The minimum requirement at the moment is Mesa 22.0.

NOTE: For older Mesa versions, use the v2.6 release.

The Vulkan beta drivers generally contain the latest driver fixes that we identify while getting games to work. The latest drivers (stable, beta or Vulkan beta tracks) are always preferred. If you're having problems, always try the latest drivers.

We have not done any testing against Intel GPUs yet.

To clone the repo you should run:

git clone --recursive https://github.com/HansKristian-Work/vkd3d-proton

in order to pull in all the submodules which are needed for building.

• wine (for widl) [for native builds]
  • On Windows this may be substituted for Strawberry Perl as it ships widl and is easy to find and install -- although this dependency may be eliminated in the future.
• Meson build system (at least version 0.49)
• glslang compiler
• Mingw-w64 compiler, headers and tools (at least version 7.0) [for cross-builds for d3d12.dll which are default]

Inside the vkd3d-proton directory, run:

./package-release.sh master /your/target/directory --no-package

This will create a folder vkd3d-master in /your/target/directory, which contains both 32-bit and 64-bit versions of vkd3d-proton, which can be set up in the same way as the release versions as noted above.

If you want to build natively (ie. for libvkd3d-proton.so), pass --native to the build script. This option will make it build using your system's compilers.

In order to preserve the build directories for development, pass --dev-build to the script. This option implies --no-package. After making changes to the source code, you can then do the following to rebuild vkd3d-proton:

# change to build.86 for 32-bit
ninja -C /your/target/directory/build.64 install

# 64-bit build.
meson --cross-file build-win64.txt --buildtype release --prefix /your/vkd3d-proton/directory build.64
ninja -C build.64 install

# 32-bit build
meson --cross-file build-win32.txt --buildtype release --prefix /your/vkd3d-proton/directory build.86
ninja -C build.86 install

# 64-bit build.
meson --buildtype release --prefix /your/vkd3d-proton/directory build.64
ninja -C build.64 install

# 32-bit build
CC="gcc -m32" CXX="g++ -m32" \
PKG_CONFIG_PATH="/usr/lib32/pkgconfig:/usr/lib/i386-linux-gnu/pkgconfig:/usr/lib/pkgconfig" \
meson --buildtype release --prefix /your/vkd3d-proton/directory build.86
ninja -C build.86 install

The intended way to use vkd3d-proton is as native Win32 DLLs (d3d12.dll and d3d12core.dll). These serve as a drop-in replacement for D3D12, and can be used in Wine (Proton or vanilla flavors), or on Windows.

vkd3d-proton does not supply the necessary DXGI components on its own. Instead, DXVK (2.1+) and vkd3d-proton share a DXGI implementation.

Native Windows use is mostly relevant for developer testing purposes. Do not expect games running on Windows 7 or 8.1 to magically make use of vkd3d-proton, as many games will only even attempt to load d3d12.dll if they are running on Windows 10.

A native Linux binary can be built, but it is not intended to be compatible with upstream Wine. A native option is mostly relevant for development purposes for the time being.

Most of the environment variables used by vkd3d-proton are for debugging purposes. The environment variables are not considered a part of API and might be changed or removed in the future versions of vkd3d-proton.

Some of debug variables are lists of elements. Elements must be separated by commas or semicolons.

• VKD3D_CONFIG - a list of options that change the behavior of vkd3d-proton.
  • vk_debug - enables Vulkan debug extensions and loads validation layer.
  • skip_application_workarounds - Skips all application workarounds. For debugging purposes.
  • nodxr - Disables DXR support.
  • dxr - DXR is normally enabled automatically. This config forces it to be enabled even when considered unsafe.
  • force_static_cbv - Unsafe speed hack on NVIDIA. May or may not give a significant performance uplift.
  • single_queue - Do not use asynchronous compute or transfer queues.
  • no_upload_hvv - Blocks any attempt to use host-visible VRAM (large/resizable BAR) for the UPLOAD heap. May free up vital VRAM in certain critical situations, at cost of lower GPU performance. A fraction of VRAM is reserved for resizable BAR allocations either way, so it should not be a real issue even on lower VRAM cards.
  • force_host_cached - Forces all host visible allocations to be CACHED, which greatly accelerates captures.
  • no_invariant_position - Avoids workarounds for invariant position. The workaround is enabled by default.
• VKD3D_DEBUG - controls the debug level for log messages produced by vkd3d-proton. Accepts the following values: none, err, info, fixme, warn, trace.
• VKD3D_SHADER_DEBUG - controls the debug level for log messages produced by the shader compilers. See VKD3D_DEBUG for accepted values.
• VKD3D_LOG_FILE - If set, redirects VKD3D_DEBUG logging output to a file instead.
• VKD3D_VULKAN_DEVICE - a zero-based device index. Use to force the selected Vulkan device.
• VKD3D_FILTER_DEVICE_NAME - skips devices that don't include this substring.
• VKD3D_DISABLE_EXTENSIONS - a list of Vulkan extensions that vkd3d-proton should not use even if available.
• VKD3D_TEST_DEBUG - enables additional debug messages in tests. Set to 0, 1 or 2.
• VKD3D_TEST_MATCH - a match string. Only the tests whose names exactly match the string will be run, e.g. VKD3D_TEST_FILTER=clear_render_target will only match tests named 'clear_render_target'. Useful for debugging or developing new tests.
• VKD3D_TEST_FILTER - a filter string. Only the tests whose names matches the filter string will be run, e.g. VKD3D_TEST_FILTER=clear_render will match tests named 'clear_render_target' or 'target_clear_render'. Useful for debugging or developing new tests.
• VKD3D_TEST_EXCLUDE - excludes tests of which the name is included in the string, e.g. VKD3D_TEST_EXCLUDE=test_root_signature_priority,test_conservative_rasterization_dxil.
• VKD3D_TEST_PLATFORM - can be set to "wine", "windows" or "other". The test platform controls the behavior of todo(), todo_if(), bug_if() and broken() conditions in tests.
• VKD3D_TEST_BUG - set to 0 to disable bug_if() conditions in tests.
• VKD3D_PROFILE_PATH - If profiling is enabled in the build, a profiling block is emitted to ${VKD3D_PROFILE_PATH}.${pid}.

The VKD3D_FRAME_RATE environment variable can be used to limit the frame rate. A value of 0 uncaps the frame rate, while any positive value will limit rendering to the given number of frames per second.

The DXVK_FRAME_RATE environment variable is also detected on VKD3D-Proton, so you may prefer to use that instead of having to remember two separate variables that do the same thing. VKD3D_FRAME_RATE, however, only applies to VKD3D (Direct3D 12) scenarios. If both variables are used, VKD3D_FRAME_RATE takes precedence.

By default, vkd3d-proton manages its own driver cache. This cache is intended to cache DXBC/DXIL -> SPIR-V conversion. This reduces stutter (when pipelines are created last minute and app relies on hot driver cache) and load times (when applications do the right thing of loading PSOs up front).

Behavior is designed to be close to DXVK state cache.

vkd3d-proton.cache (and vkd3d-proton.cache.write) are placed in the current working directory. Generally, this is the game install folder when running in Steam.

VKD3D_SHADER_CACHE_PATH=/path/to/directory overrides the directory where vkd3d-proton.cache is placed.

VKD3D_SHADER_CACHE_PATH=0 disables the internal cache, and any caching would have to be explicitly managed by application.

When explicit shader cache is used, the need for application managed pipeline libraries is greatly diminished, and the cache applications interact with is a dummy cache. If the vkd3d-proton shader cache is disabled, ID3D12PipelineLibrary stores everything relevant for a full cache, i.e. SPIR-V and PSO driver cache blob. VKD3D_CONFIG=pipeline_library_app_cache is an alternative to VKD3D_SHADER_CACHE_PATH=0 and can be automatically enabled based on app-profiles if relevant in the future if applications manage the caches better than vkd3d-proton can do automagically.

Pass -Denable_profiling=true to Meson to enable a profiled build. With a profiled build, use VKD3D_PROFILE_PATH environment variable. The profiling dumps out a binary blob which can be analyzed with programs/vkd3d-profile.py. The profile is a trivial system which records number of iterations and total ticks (ns) spent. It is easy to instrument parts of code you are working on optimizing.

These features are only meant to be used by vkd3d-proton developers. For any builtin RenderDoc related functionality pass -Denable_renderdoc=true to Meson.

• VKD3D_SHADER_DUMP_PATH - path where shader bytecode is dumped. Bytecode is dumped in format of $hash.{spv,dxbc,dxil}.
• VKD3D_SHADER_OVERRIDE - path to where overridden shaders can be found. If application is creating a pipeline with $hash and $VKD3D_SHADER_OVERRIDE/$hash.spv exists, that SPIR-V file will be used instead.
• VKD3D_AUTO_CAPTURE_SHADER - If this is set to a shader hash, and the RenderDoc layer is enabled, vkd3d-proton will automatically make a capture when a specific shader is encountered.
• VKD3D_AUTO_CAPTURE_COUNTS - A comma-separated list of indices. This can be used to control which queue submissions to capture. E.g., use VKD3D_AUTO_CAPTURE_COUNTS=0,4,10 to capture the 0th (first submission), 4th and 10th submissions which are candidates for capturing. If VKD3D_AUTO_CAPTURE_COUNTS is -1, the entire app runtime can be turned into one big capture. This is only intended to be used when capturing something like the test suite, or tiny applications with a finite runtime to make it easier to debug cross submission work.

If only VKD3D_AUTO_CAPTURE_COUNTS is set, any queue submission is considered for capturing. If only VKD3D_AUTO_CAPTURE_SHADER is set, VKD3D_AUTO_CAPTURE_COUNTS is considered to be equal to "0", i.e. a capture is only made on first encounter with the target shader. If both are set, the capture counter is only incremented and considered when a submission contains the use of the target shader.

For debugging GPU hangs, it's useful to know where crashes happen. If the build has trace enabled (non-release builds), breadcrumbs support is also enabled.

VKD3D_CONFIG=breadcrumbs will instrument command lists with VK_AMD_buffer_marker or VK_NV_device_checkpoints. On GPU device lost or timeout, crash dumps are written to the log. For best results on RADV, use RADV_DEBUG=syncshaders. The logs will print a digested form of the command lists which were executing at the time, and attempt to narrow down the possible range of commands which could have caused a crash.

It is possible to log the output of replaced shaders, essentially a custom shader printf. To enable this feature, VK_KHR_buffer_device_address must be supported. First, use VKD3D_SHADER_DEBUG_RING_SIZE_LOG2=28 for example to set up a 256 MiB ring buffer in host memory. Since this buffer is allocated in host memory, feel free to make it as large as you want, as it does not consume VRAM. A worker thread will read the data as it comes in and log it. There is potential here to emit more structured information later. The main reason this is implemented instead of the validation layer printf system is run-time performance, and avoids any possible accidental hiding of bugs by introducing validation layers which add locking, etc. Using debugPrintEXT is also possible if that fits better with your debugging scenario. With this shader replacement scheme, we're able to add shader logging as unintrusive as possible.

# Inside folder full of override shaders, build everything with:
make -C /path/to/include/shader-debug M=$PWD

The shader can then include #include "debug_channel.h" and use various functions below.

void DEBUG_CHANNEL_INIT(uvec3 ID);

is used somewhere in your replaced shader. This should be initialized with gl_GlobalInvocationID or similar. This ID will show up in the log. For each subgroup which calls DEBUG_CHANNEL_INIT, an instance counter is generated. This allows you to correlate several messages which all originate from the same instance counter, which is logged alongside the ID. An invocation can be uniquely identified with the instance + DEBUG_CHANNEL_INIT id. DEBUG_CHANNEL_INIT can be called from non-uniform control flow, as it does not use barrier() or similar constructs. It can also be used in vertex and fragment shaders for this reason.

void DEBUG_CHANNEL_MSG();
void DEBUG_CHANNEL_MSG(uint v0);
void DEBUG_CHANNEL_MSG(uint v0, uint v1, ...); // Up to 4 components, can be expanded as needed up to 16.
void DEBUG_CHANNEL_MSG(int v0);
void DEBUG_CHANNEL_MSG(int v0, int v1, ...); // Up to 4 components, ...
void DEBUG_CHANNEL_MSG(float v0);
void DEBUG_CHANNEL_MSG(float v0, float v1, ...); // Up to 4 components, ...

These functions log, formatting is #%x for uint, %d for int and %f for float type.

If -Denable_descriptor_qa=true is enabled in build, you can set the VKD3D_DESCRIPTOR_QA_LOG env-var to a file. All descriptor updates and copies are logged so that it's possible to correlate descriptors with GPU crash dumps. enable_descriptor_qa is not enabled by default, since it adds some flat overhead in an extremely hot code path.

If VKD3D_CONFIG=descriptor_qa_checks is set with a build which enables -Denable_descriptor_qa=true, all shaders will be instrumented to check for invalid access. In the log, you will see this to make sure the feature is enabled.

932:info:vkd3d_descriptor_debug_init_once: Enabling descriptor QA checks!

The main motivation is the tight integration and high performance. GPU-assisted debugging can be run at well over playable speeds.

============
Fault type: HEAP_OUT_OF_RANGE
Fault type: MISMATCH_DESCRIPTOR_TYPE
CBV_SRV_UAV heap cookie: 1800
Shader hash and instruction: edbaf1b5ed344467 (1)
Accessed resource/view cookie: 0
Shader desired descriptor type: 8 (STORAGE_BUFFER)
Found descriptor type in heap: 0 (NONE)
Failed heap index: 1024000
==========

The instruction (1), is reported as well, and a disassembly of the shader in question can be used to pinpoint exactly where things are going wrong. Dump all shaders with VKD3D_SHADER_DUMP_PATH=/my/folder, and run spirv-cross -V /my/folder/edbaf1b5ed344467.spv. (NOTE: clear out the folder before dumping, existing files are not overwritten). The faulting instruction can be identified by looking at last argument, e.g.:

uint fixup_index = descriptor_qa_check(heap_index, descriptor_type, 1u /* instruction ID */);

============
Fault type: MISMATCH_DESCRIPTOR_TYPE
CBV_SRV_UAV heap cookie: 1800 // Refer to VKD3D_DESCRIPTOR_QA_LOG
Shader hash and instruction: edbaf1b5ed344467 (1)
Accessed resource/view cookie: 1802 // Refer to VKD3D_DESCRIPTOR_QA_LOG
Shader desired descriptor type: 8 (STORAGE_BUFFER)
Found descriptor type in heap: 1 (SAMPLED_IMAGE)
Failed heap index: 1025
==========

============
Fault type: DESTROYED_RESOURCE
CBV_SRV_UAV heap cookie: 1800
Shader hash and instruction: edbaf1b5ed344467 (2)
Accessed resource/view cookie: 1806
Shader desired descriptor type: 1 (SAMPLED_IMAGE)
Found descriptor type in heap: 1 (SAMPLED_IMAGE)
Failed heap index: 1029
==========

For when you're absolutely desperate, there is a way to debug GPU hangs. First, install umr and make the binary setsuid.

ACO_DEBUG=force-waitcnt RADV_DEBUG=hang VKD3D_DESCRIPTOR_QA_LOG=/somewhere/desc.txt %command%

It is possible to use RADV_DEBUG=hang,umr as well, but from within Wine, there are weird things happening where UMR dumps do not always succeed. Instead, it is possible to invoke umr manually from an SSH shell when the GPU hangs.

#!/bin/bash

mkdir -p "$HOME/umr-dump"

# For Navi, older GPUs might have different rings. See RADV source.
umr -R gfx_0.0.0 > "$HOME/umr-dump/ring.txt" 2>&1
umr -O halt_waves -wa gfx_0.0.0 > "$HOME/umr-dump/halt-waves-1.txt" 2>&1
umr -O bits,halt_waves -wa gfx_0.0.0 > "$HOME/umr-dump/halt-waves-2.txt" 2>&1

A folder is placed in ~/radv_dumps* by RADV, and the UMR script will place wave dumps in ~/umr-dump.

First, we can study the wave dumps to see where things crash, e.g.:

    pgm[6@0x800120e26c00 + 0x584 ] = 0xf0001108		image_load v47, v[4:5], s[48:55] dmask:0x1 dim:SQ_RSRC_IMG_2D unorm
    pgm[6@0x800120e26c00 + 0x588 ] = 0x000c2f04	;;
    pgm[6@0x800120e26c00 + 0x58c ] = 0xbf8c3f70		s_waitcnt vmcnt(0)
 *  pgm[6@0x800120e26c00 + 0x590 ] = 0x930118c0		s_mul_i32 s1, 64, s24
    pgm[6@0x800120e26c00 + 0x594 ] = 0xf40c0c09		s_load_dwordx8 s[48:55], s[18:19], s1
    pgm[6@0x800120e26c00 + 0x598 ] = 0x02000000	;;

excp: 256 is a memory error (at least on 5700xt).

TRAPSTS[50000100]:
	                excp:      256 |         illegal_inst:        0 |           buffer_oob:        0 |           excp_cycle:        0 |
	       excp_wave64hi:        0 |          xnack_error:        1 |              dp_rate:        2 |      excp_group_mask:        0 |

We can inspect all VGPRs and all SGPRs, here for the image descriptor.

    [  48..  51] = { 0130a000, c0500080, 810dc1df, 93b00204 }
    [  52..  55] = { 00000000, 00400000, 002b0000, 800130c8 }

Decode the VA and study bo_history.log. There is a script in RADV which lets you query history for a VA. This lets us verify that the VA in question was freed at some point. At point of writing, there is no easy way to decode raw descriptor blobs, but when you're desperate enough you can do it by hand :|

In pipeline.log we have the full SPIR-V (with OpSource reference to the source DXIL/DXBC) and disassembly of the crashed pipeline. Here we can study the code to figure out which descriptor was read.

    // s7 is the descriptor heap index, s1 is the offset (64 bytes per image descriptor),
    // s[18:19] is the descriptor heap.
    s_mul_i32 s1, 64, s7                                        ; 930107c0
    s_load_dwordx8 s[48:55], s[18:19], s1                       ; f40c0c09 02000000
    s_waitcnt lgkmcnt(0)                                        ; bf8cc07f
    image_load v47, v[4:5], s[48:55] dmask:0x1 dim:SQ_RSRC_IMG_2D unorm ; f0001108 000c2f04

    [   4..   7] = { 03200020, ffff8000, 0000002b, 00000103 }

Which is descriptor index #259. Based on this, we can inspect the descriptor QA log and verify that the application did indeed do something invalid, which caused the GPU hang.