# Change Log

## 3.0

A new major release, yay!
A few milestones have been reached over the last year, warranting a new major bump.
It's been quite a while since the last release due to new things coming up constantly.
These tags are mostly arbitrary anyway, and tend to be done when islands of calm and stability emerge.

### Major items

#### DXBC shader backend rewrite

@doitsujin rewrote the entire DXBC backend, replacing our legacy vkd3d-shader path.
DXVK and vkd3d-proton now share the same DXBC frontend which gives us clean,
"readable" (as readable as DXBC can be) and lean IR to work with.
dxil-spirv standalone project now supports DXBC as well as a result.

Lots of games which used to be completely broken before due to bugs and missing features
in the legacy vkd3d-shader backend are now fixed. E.g. Red Dead Redemption 2 runs just fine now in D3D12 mode.
Some recently released DXBC based games also only work on the new path.
The amount of regressions found the last months in DXBC games has been very minor,
but it's possible there are still bugs in this area.
However, given that DXVK uses it now as well, it's been battle tested quite extensively already.

#### FSR4 support

We added support for AGS WMMA intrinsics through `VK_KHR_cooperative_matrix` and `VK_KHR_shader_float8`,
which is enough to support FSR4.
Note that these shaders are tightly coded for AMD GPUs with some implementation defined behavior
(particularly around matrix layouts), and they will not necessarily work on other GPU vendors.

There is also a quite hacky emulation path of this which relies on int8 and float16 cooperative matrix support,
which can run on older GPUs at significant performance cost (and some cost to theoretical correctness).

Note that the default "official" build of vkd3d-proton only exposes this feature when the native
`VK_KHR_shader_float8` is properly supported, i.e. RDNA4+ only.
The emulation path is available when building from source with the appropriate build flags.
The decision to not include this emulation path by default is over my pay grade.
The aim is to be able to ship FSR4 in a more proper way in Proton.

### Features

We've more or less caught up on the things we can feasibly implement,
so there isn't much exciting stuff happening on the feature front.

- Implemented experimental support for D3D12 work graphs. No real-world content ships this yet.
  This implementation is far from complete,
  but it works on "any" GPU since we emulate the feature with normal compute shaders.
  Funnily enough, the performance of this emulation can massively outperform native driver implementations of the feature
  in many scenarios we've tested (at the cost of some extra VRAM usage).
  See `docs/` for more details on implementation and some performance numbers.
- Expose `AdvancedTextureOpsSupported` by default from SM 6.7 if `VK_KHR_maintenance8` is supported.
- Expose the recently added sparse TIER_4.
- Bump exposed D3D12SDKVersion to latest 618.
- Experimentally expose support for opacity micromaps.
  There are some details which aren't quite compatible with the D3D12 API, but some basic demo content is working fine.
- Add support for AMD_anti_lag when exposed. The current implementation does not take frame-gen into account.
- Implement support for tight alignment from recent AgilitySDK.
- Add support for shared resource path on upstream Wine.

### Performance

- Overhaul the texture copy batching situation.
  The new batching logic should be able to improve performance in many more cases than before.
  - Implemented support for `VK_KHR_unified_image_layouts`.
    Image copy batching in particular can take advantage of this to avoid a lot of unnecessary barriers.
- Removed manual clear workaround on newer (6.15.9+) kernels on AMD, where an old kernel regression was finally fixed.
  Kernels older than 6.10 are also not affected by this workaround.
- Use push descriptor path on Qualcomm GPUs over BDA for speed.
- Improve handling of GDeflate when decompression extension is not available.
  We now ship our own fallback shader in GLSL instead of the more awkward HLSL shader that dstorage ships.
- Bump DGC scratch size on NVIDIA. Should avoid some massive perf drops in Halo Infinite on NVIDIA.
- Add performance optimization for The Last of Us Part 1 to prefer 2D tiling on 3D images.
  Requires [an update to Mesa](https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38084) as well to get the proper effect.
- Handle depth/stencil <-> color image copies better when `VK_KHR_maintenance8` is supported.
- Make use of `VK_EXT_zero_initialize_device_memory` to avoid manual clears on allocation.

### Fixes

- Emit render pass barriers as expected on tiled GPUs. Fixes misc rendering bugs reported on e.g. Turnip.
  - For performance reasons, we deliberately skirt the spec a bit on desktop GPUs.
- Fixed a bunch of minor correctness problems exposed by new Vulkan-ValidationLayers.
- Adjust how `PointSamplingAddressesNeverRoundUp` is reported to match recent driver behaviors.
- Fix overflow bugs in massive (> 4GiB) sparse resource handling.
- Fix reporting of some esoteric format properties to better match native drivers.
- Fix handling of NULL acceleration structure descriptors.
- Fix some texturing bugs in Helldivers II on NVIDIA.
- Fix some bugs with memory type handling on very old NVIDIA GPUs.
- Fix bug when pixel shader includes root signature.
- Make ClearUAV barrier insertion the default now.
  Too many games screw this up, and D3D12 drivers seem to do it by default.
- Fix shared fences when initial value is not 0. Fixes some Star Citizen issues.
- Fix rare deadlock scenario in Ninja Gaiden 4.
  Fixes some long-standing issues with how we deal with fence rewinds.
- Fix some long-standing issues with how we deal with placed MSAA resources and alignment.
- Make sure we don't clear memory of imported resources.
  This doesn't fix any known games, but you never know :V
- Improve correctness for many odd GS/HS/DS corner cases with primitive types and API validation.
- Fixes crashes when index buffer SizeInBytes = 0, but VA was invalid.
  Seen in some Saber Interactive games.
- Fixes some potential deadlocks in VR interop APIs when multiple threads attempt to acquire Vulkan queue.
- Fixes 16-bit aligned structured buffer strides. Not observed in any real content, but you never know!

### Workarounds

- Add FF VII rebirth sync bugs workarounds. Fixes some rare GPU hangs.
- Add misc AMD workarounds for Monster Hunter Wilds caused by bugged hardware around sparse SMEM.
  - A proper hardware workaround in RADV is still pending.
- Workaround some Starfield bugs around `NonUniformResourceIndex` use.
- Add performance workarounds for extremely large tessellation factors used in misc new Koei Tecmo games.
- Add Wreckfest 2 workarounds for illegal texture placement aliasing. Fixes some broken textures.
- Add barrier in Satisfactory that game missed. Fixes some corrupt rendering especially on AMD.
- Ignore NOT_CLEARED flags on allocation in all games now. Native drivers seem to always clear regardless of the flag,
  and e.g. Street Fighter 6 relies on NOT_CLEARED memory to actually be cleared :(
- Workaround some issues with RGB9E5 and alpha write masks observed in Ninja Gaiden 4.
- Add missing barrier in Death Stranding (the older build, not Director's Cut).
- Add missing barrier in Wuthering Waves.
- Workaround bugged uninitialized loop variable in Dune MMO.
- Disable UAV compression in Spider-Man Remastered. Fixes some weird RT issues on RDNA2.
- Add Root CBV robustness workaround for Gray Zone Warfare.
- Disables color compression in Rise of the Tomb Raider. Fixes some glitches due to game bug on AMD.
- Workaround some bugs in Port Royal benchmark.
- Workaround Mafia: Definitive Edition hanging GPU when using FSR on startup due to use-after-free.
  - The workaround applies to all uses of FSR. Plausibly workaround a hang in MGS: Delta as well, but not confirmed it was this bug.
- Workaround Control RT path occasionally observing NaNs due to bad normalize() patterns.
- Workaround Final Fantasy Tactics Ivalice Chronicles illegally using dynamically indexed root constants.

### Misc

- Added a lot more debug instrumentation as usual.
  - Not user facing, so omitting details.
- Make it a bit easier to use vkd3d-proton in Linux-native projects.
- Remove `DXVK_FRAME_RATE` to align with DXVK's removal. Only `VKD3D_FRAME_RATE` remains (at least for now).

## 2.14.1

This is a bug-fix release which resolves some regressions introduced in 2.14.

- Fix a crash on start-up which affected GPUs without sparse support. E.g. Intel iGPU or Turnip.
  Crash could happen even if that GPU was the secondary GPU on the system.
- Fix a memory allocation issue affecting NVK.
- Fix a CPU performance regression issue affecting Horizon Zero Dawn Remastered on NVIDIA GPUs.
  This fix might improve CPU performance in other games too, but unverified.
- Not a regression fix, but add a `no_upload_hvv` workaround for Arma Reforger to workaround weird asset loading behavior.

## 2.14

Rolls up the usual collection of new features, performance improvements, bug fixes and the copious amount of game workarounds,
just in time for the holidays.

### Features

- Implement DXGI frame statistics (exposed by DXVK DXGI).
- Implement a global frame rate limiter (see `VKD3D_FRAME_RATE` or `DXVK_FRAME_RATE`).
  Also improves behavior of presentation with swap interval > 1 since we use frame limiter instead
  of duplicated presents now. Also allows support for full-screen frame rate targets in DXGI which normally would imply a mode change.
- Implement support for planar video formats such as NV12.
- Implement D24 depth bias correctly now on AMD when `VK_EXT_depth_bias_control` is supported.
- Expose a new command interop interface that allows e.g. dxvk-nvapi to implement DLSS3 frame generation.
- Use VK_KHR_compute_shader_derivatives when available.
- Use VK_EXT_device_generated_commands when available. Expose execute indirect tier 1.1.
- Implement GPU upload heap from latest AgilitySDKs. Allows explicit control over ReBAR instead of heuristic based hacks in games that use the new API.
- Implement ID3DDestructionNotifier. Fixes some particular games that expect this to be supported.

### Performance

- Reduce some VRAM bloat on RDNA2 and 3 GPUs when `VK_MESA_image_alignment_control` is exposed.
- Improve CPU overhead for games that query swapchain format support over and over.
- Remove old heuristic that preferred 2 frames of latency depending on BufferCount used.
  The default on DXGI is 3, and using 2 caused some performance issues in various games with GPU starvation,
  especially on Deck. `VKD3D_SWAPCHAIN_LATENCY_FRAMES` is still available as an override to force a tighter default.
- Rewrite queue submission logic to deal better with difficult submission patterns such as FSR3 3.1 Frame Generation.
  On implementations with only one graphics queue, vkd3d-proton will now attempt to do basic software scheduling of GPU work.
  This may regress GPU performance in some other cases and `VKD3D_CONFIG=no_staggered_submit` is a way to disable this code path.
  One particularly big improvement is FF XVI on RADV with FSR 3 frame-gen, with almost doubled performance in some cases.
  We are still awaiting a proper kernel-level fix for this problem to be fully resolved.
- Rewrite queue submission logic to use fewer "dummy" wait/signal submissions.
  Works around pathological CPU overhead in amdgpu taking 20ms+ to submit work in some cases.
- Rewrite queue submission logic for sparse updates to be more efficient.

### Fixes and workarounds

- Rework various multi-sampling queries to be more spec correct.
- Workaround bugged MSAA behavior in World of Warcraft.
- Workaround buggy/questionable use of ID3D12PipelineLibrary in FF XVI.
- Always use native 16-bit integers for min16int. Fixes some real-world bugs where shaders expect min16int is always implemented as 16-bit.
- Workaround game bug leading to GPU hang in Dragon Age: Veilguard on RADV.
- Always emit proper floating-point environment modes in DXBC shaders. Fixes glitched eyes in Dragon Age: Veilguard on NV.
- Fix potential use-after-free bug for some sparse resource update cases.
- Correctly validate when application attempts to allocate a too large descriptor heap.
  Fixes Stalker 2 entering into undefined behavior.
- A lot of misc fixes in dxil-spirv as usual.
- Workaround broken amdgpu zerovram behavior on 6.10+ kernels. Fixes random extreme glitchiness in Helldivers 2 on AMD.
- Workaround NV issue which lead to GPU hang when loading a save file in Star Wars: Outlaws.
- Fix copying between BC <-> RGBA images in some cases.
- Add workaround for a game bug in The First Descendant which lead to broken cubemap reflections in some cases.
- Workaround Skull & Bones crashing on startup on NV GPUs by disabling Reflex support.
- Workaround Hunt: Showdown missing precise qualifiers on vertex shaders, leading to glitched rendering.
- Workaround poor CPU performance in Red Dead Redemption.

### Misc / Debug

- Add support for instruction_qa_checks. For deep debug, allows us to be notified when NaNs and Infs are generated in shaders.
  For internal QA use.
- Add fine-grained control of QA behavior on a per-shader basis. For narrowing down issues.
- Remove a bunch of old and obsolete workarounds for NV drivers. New cutoff is 535 series.
- Bump exposed SDKVersion to 614 to match latest stable AgilitySDK.
- Add an optional code path to support DXBC via the official dxilconv library.
  This code is not enabled in release builds,
  and is currently only intended as a path to take advantage of QA instrumentation for DXBC shaders.

## 2.13

### Features

- Implement Shader Model 6.8 min-spec
  - `SV_StartInstanceLocation`
  - `SV_StartVertexLocation`
  - WaveSize range
  - Implement Vulkan texturing catch-up features (esoteric comparison sampling functions)
- Implement interop for OpenVR / OpenXR on Proton
- Correctly support `NULL` index buffers with `VK_KHR_maintenance6`.
- Implement `VK_MESA_image_alignment_control`. Reduces memory bloat on AMD cards in particular.

### Fixes

- Reimplement `VK_NV_low_latency2` to fix some issues with heavy stuttering caused by non-monotonic frame IDs.
  Relies on a more recent dxvk-nvapi which can paper over API design issues in Reflex API.
  Requires a more recent NVIDIA driver which fixes some bugs exposed in this new code.
  On older NVIDIA drivers, it should *run*, but low-latency will not kick in as expected.
- Explicitly disable variable-rate shading when depth-stencil is written in shader.
  Fixes glitched hair rendering in Hellblade 2.
- Correctly expose MSAA features for depth-stencil. Fixes Arma Reforger.
- Fix bugs in MSAA resolve implementation when dealing with custom resolve formats. Fixes Arma Reforger.
- Fix validation error in internal query resolve shader.
- Fix some bugs in wave-ops where helper lanes participated where they were not supposed to.
  Fixes some WaveMatch / WaveMultiPrefix use-cases in the wild.
- Various dxil-spirv fixes to fix invalid control-flow as always.

### Performance

- Tweak how we opt-in to ReBAR for UPLOAD heaps. Now, only > 8 GB cards will get it.
  On 8 GB cards, we were regularly hitting the upper limits of what the GPU could hold in VRAM,
  and using ReBAR would be detrimental to performance since there was risk of more important
  memory being demoted to system memory. Works well together with `VK_MESA_image_alignment_control`
  to free up significant amounts of VRAM. Performance gains from ReBAR on 8 GB were also found to be minimal
  compared to the larger GPUs since we quickly exhausted the limited 512 MiB budget anyway.
- Sub-allocate small image heaps. Avoids heavy stutter in Ghost of Tsushima on desktop.
  (Steam Deck code path does not seem to use small heaps to begin with).
- Improve performance with ROV when used with more complicated shader code patterns.

### Workarounds

- Implement a crude workaround for depth-stencil sparse and MSAA sparse.
  - Just allocates a committed resource instead. Not correct, but good enough band-aid.
  - Allows SottR to run on RADV.
- Disable NV_dgcc on Halo Infinite on NV drivers.
- Workaround a missing barrier in AC: Mirage causing random corrupt geometry.

### Misc

- Split vkd3d-proton shader cache up by .exe name when using a unified directory with `VKD3D_SHADER_CACHE_PATH`.
- Implement `VK_EXT_device_address_binding_report`.

## 2.12

### Features

- Implement support for NVIDIA Reflex through `VK_NV_low_latency2`. Thanks to NVIDIA for contributing implementation
- Implement D3D12 render pass API (tier 0)
- Implement ID3D12DeviceRemovedExtendedDataSettings stubs. Fixes some games that rely on this existing
- Implement `VK_EXT_device_fault`. Makes it possible to grab fault information and vendor binary if supported
- Implement `VK_EXT_swapchain_maintenance1`
  - Allows seamless transition between V-Sync and tearing present modes without stutter
  - Implemented on both Mesa and NV drivers
- Expose Shader Model 6.7 by default if
  `VK_KHR_shader_maximal_reconvergence` and `VK_KHR_shader_quad_control` are supported
- Add optimized descriptor copy path on Intel Arc GPUs that support `VK_EXT_descriptor_buffer`
- Implement fallback for compute shader derivatives on NVIDIA Pascal and older GPUs.
  Allows exposing Shader Model 6.7 by default on Pascal as well (albeit with some known cases where it does not work).
  The workaround is expected to work with any known use of SM 6.6 compute derivatives in the wild

### Fixes

- Fix Atlas Fallen black screen due to edge case with MinLODClamp
- Correctly disable alpha-to-coverage if sampler mask is exported
- Fix format feature reports for `DXGI_FORMAT_UNKNOWN`
- Relax root signature compatibility rules when compiling Ray Tracing pipelines.
  Fixes GPU hang on NV in Warhammer: Darktide
- Fix GPU hang on NV in UE5 Lyra demo
- Explicitly validate stage IO signatures in PSO creation similar to native D3D12 runtime.
  Fixes some scenarios where a game attempts to create an invalid pipeline that should have failed creation
  on native D3D12

### Workarounds

- Workaround crash in Resident Evil 4 RT mode when tessellation is enabled
- Workaround mesh shader glitches on NVIDIA in several UE5 titles
- Workaround GPU hang on NVIDIA in World of Warcraft when MSAA is enabled
- Disable RT by default in Persona 3 Reload on Deck

### Performance

- Implement `VK_NV_raw_access_chains`. Significantly improves GPU performance on NV GPUs in some games.
  Games using DXBC instead of DXIL are expected to see more improvements.
  Not all games are expected to see an uplift
- Fix extremely poor GPU performance in some locations in Persona 3 Reload

### Debug

- Add support for `VKD3D_QUEUE_PROFILE`, a simple system profiling method
  - Includes `VK_NV_low_latency2` support to debug NVIDIA Reflex sleeps
- Root signature blobs are also dumped when dumping shaders
  - A simple CLI tool to inspect the root-sig blobs is included in `programs/`
- Misc improvements to breadcrumbs, debug ring, etc
- Pipeline creation failure now dumps PSO creation commands in log

## 2.11.1

This release is a minor bug-fix release before the holidays.

- Implement COLOR -> STENCIL fallback copy on NVIDIA
- Implement SM 6.6 ResourceDescriptorHeap[] + UAV counters correctly on RADV
- Fix bugged implementation of DXBC resinfo instruction, affecting Avatar: Frontiers of Pandora
- Fix memory type used for DGC preprocess memory on NVIDIA (~5% performance, YMMV)
- Fix crash in Callisto Protocol when booting game with DXR support
 
#### More complete MSAA resolve implementation

- Add depth-stencil resolve
- Support typeless formats
- Add MIN/MAX resolve modes
- Implement missing code paths on NVIDIA
 
#### Workarounds

- Update workaround for GPU hang in CP77 when using DXR for patch 2.1.
- Remove workaround for NO_DGCC in Halo Infinite on NVIDIA.
- Workaround game bug in Pioneers of Pagonia causing GPU hangs on RADV.

## 2.11

This release rolls up a bunch of features, perf improvements and bug fixes / workarounds as usual.

### Features

#### DXR enabled by default

`VKD3D_CONFIG=dxr` is default now, and no longer needed.
There are some special cases where DXR is not enabled by default. The only such current example is
"Hellblade: Senua's Sacrifice" on Deck which force-enables DXR if it is supported, even on Deck.
New semantics are:

- `dxr`: Force-enable DXR, even when it is considered unsafe
- `nodxr`: Disable DXR
- `dxr11`: Removed. `dxr` already implied DXR 1.1 anyway

#### Sampler feedback

This feature was the last feature required for FL 12.2 and is implemented through emulation.
As demonstrated in the [implementation docs](https://github.com/HansKristian-Work/vkd3d-proton/blob/master/docs/sampler_feedback.md), all
native implementations of this feature are fundamentally broken in some way.
There's also no known game that ships requiring this feature, so we just consider this a checkbox feature.

#### DX Ultimate (FL 12.2) now exposed by default

On RDNA2+ and Turing+ we can finally expose the DX Ultimate feature set!

#### Misc

- Implement a bunch of missing "Vulkan-on-D3D12" features
  - IndependentFrontAndBackStencilRefMaskSupported
  - TriangleFanSupported
  - DynamicIndexBufferStripCutSupported
  - DynamicDepthBiasSupported
  - NonNormalizedCoordinateSamplersSupported
  - MismatchingOutputDimensionsSupported
  - PointSamplingAddressesNeverRoundUp
  - RasterizerDesc2Supported
    - Explicit line rasterization mode
  - NarrowQuadrilateralLinesSupported
  - AnisoFilterWithPointMipSupported
- Implement missing MSAD instruction in DXIL, allowing FSR3 to run
- Implement some esoteric DXR features
  - Implement support for multiple mismatching global root signatures in DXR
    - Fixes crash in Battlefield V
  - Implement support for LOCAL_ON_EXTERNAL dependencies in DXR
    - Fixes DXR in Warhammer: Darktide
- Implement support for ExecuteIndirect + Mesh shaders with state changes
  - Currently unused by games

### Performance

- Improve performance of NV_device_generated_commands and NV_device_generated_commands_compute by
  reordering and batching command preprocessing
  - We have observed 15% FPS gains in Halo Infinite on RADV
  - 1-2% in Starfield in some test locations
  - Needs pending Mesa work to land to take advantage of this improvement
- Tune memory allocation patterns for DGC preprocess buffers
  - Avoids a lot of allocation churn
  - Greatly reduces CPU overhead on NV

### Workarounds

- Work around RADV bug causing GPU hang in RE4: Separate Ways DLC
- Work around RADV bug causing GPU hang in Lords of the Fallen
- Work around Witcher 3 bug causing broken shadows and GPU hangs when enabling DXR
- Work around Cyberpunk 2077 bug when RT is enabled, where game would cause spurious GPU hangs due to accessing descriptor heap out of bounds
- Work around Windjammers 2 bug causing random crashes on startup
- Add support for VK_EXT_image_compression_control to allow for more fine-grained workarounds for broken games running on RADV
- Enable NV_device_generated_commands_compute on latest NV beta drivers
  - 545.x drivers are still disabled until a fix can be confirmed on shipping drivers
- Remove CURB_MEMORY_PSO_CACHE workaround on Mesa 23.2+
  - Should reduce overhead in PSO creation

### Fixes

- Misc dxil-spirv changes to fix various bugs in game shaders as usual
- Fix Jurassic World Evolution 2 crashing when enabling DXR
- Fix some deprecation warnings in Meson build system
  - Some submodule locations moved, which may cause minor disruption

## 2.10

This release rolls up a ton of bug fixes, game and driver workarounds, and other improvements.

### Features

#### DirectStorage MetaCommands

We can now make use of `NV_memory_decompression` to implement
GPU accelerated GDeflate compression in DirectStorage.
This is demonstrated to work in Ratchet & Clank: Rift Apart.

We also worked around an NV driver bug when using the fallback GDeflate shader.
The fallback works on RADV.

#### Enhanced Barriers

NOTE: This isn't all that well tested because there are no games shipping with this yet to our knowledge.

#### Device generated commands for compute

With `NV_device_generated_commands_compute` we can efficiently implement
Starfield's use of ExecuteIndirect which hammers multi-dispatch COMPUTE + root parameter changes.
Previously, we would rely on a very slow workaround.

NOTE: This feature is currently only enabled on RADV due to driver issues.

#### Misc

- Support Root Signature version 1.2
- Implement Shader Model 6.7
  - Includes all SM 6.7 features like AdvancedTextureOps, WaveOpsIncludeHelperLanes
  - Caveat: Technically not Vulkan spec compliant implementation, but works fine on at least NV and RADV. Currently implemented as an opt-in option for now in case some game relies on it to work
- Implement CreateSampler2
- Expose inverted viewport / height feature
- Implement RelaxedFormatCasting feature from Enhanced Barriers
- Implement support for adjacency topologies
- Support A8_UNORM format properly by using `VK_KHR_maintenance5`, allowing A8_UNORM UAVs to work correctly
- Handle range checked index buffers correctly with `VK_KHR_maintenance5`

#### New extension use

- VK_EXT_dynamic_rendering_unused_attachments
- VK_KHR_maintenance5
- VK_NV_device_generated_commands_compute

### Performance

- Batch acceleration structure builds. Massively improves build performance on at least RADV.
- Massively improve ExecuteIndirect performance when using COMPUTE + root parameter changes when `VK_NV_device_generated_commands_compute` is enabled.

### Fixes

- Fix root signature creation from DXIL library target (DXR) blobs
- Fix some dual source blending PSOs scenarios. Fixes Star Wars Battlefront II
- Implement wave operations in pixel shaders more strictly according to D3D12 rules
- Fix spurious hangs in Ashes of Singularity when using shared fences and wait-before-signal
- Fix PSO caching bug in mesh shaders. Fixes mesh shaders in Unreal Engine 5
- Fix udiv remainder in DXBC, which fixed some Xenia bugs
- Fix query heap tracking bug that was exposed by NV Streamline
- Various DXIL -> SPIR-V fixes as usual
- Rewrote descriptor set layouts to be more robust against application bugs
  - Motivated by Armored Core VI bug (see below)
  - Native D3D12 drivers are also robust against these application bugs :(

### Workarounds

- Workaround bad ReBAR performance in Age of Wonders 4
- Remove workaround for `KHR_present_wait` on NV 535+ drivers
- Workaround Starfield memory corruption issue where it does not correctly query for 4 KiB alignment
- Disable ReBAR usage on Halo Infinite to workaround very poor CPU performance
- Workaround Street Fighter 6 bug causing spurious GPU hangs
  - Also appears to have worked around GPU hangs in Resident Evil 2
- Workaround Armored Core VI bug causing GPU hang on Balteus fight in chapter 1
- Workaround "firefly" glitches in Resident Evil 4 caused by dubious min16float usage
- Workaround "firefly" glitches in Monster Hunter Rise caused by dubious shader requiring particular precise math
- Workaround Unreal Engine 5 breaking if mesh shaders are exposed, but not barycentrics
- Workaround NV driver bug with TIMESTAMP query heaps that could cause spurious GPU hangs
- Workaround broken CFG code generation in Xenia's DXBC emitter

## 2.9

This release rolls up various development happening over the last months.

### d3d12core.dll split

Some games started assuming that the DLLs were laid out similar to AgilitySDK, where
d3d12.dll is just a loader, and d3d12core.dll contains the real implementation.
vkd3d-proton now implements this split as well. It is possible that various scripts must be updated
to accomodate both DLLs now. Once d3d12.dll is installed in a prefix,
only d3d12core.dll needs to be updated, as d3d12.dll is just a trivial shim either way.

### Performance improvements

- Greatly reduce system memory requirements on the first run of an application.
  SPIR-V code was held in memory "just in case" it had to be recompiled later, but this is no longer the case.
- Use `VK_EXT_graphics_pipeline_libraries` to avoid shader compilation stutter in some extreme edge cases.
- Improve performance with certain bad occlusion query patterns in e.g. Elden Ring.
- Improve CPU performance of `VK_EXT_descriptor_buffer` even further with vendor-specific "ultra-fast" paths.
  - Our microbenchmark for single descriptor copies are now significantly faster than native D3D12 drivers on both RADV and NVIDIA.
  - Intel performance numbers are TBD, but we expect a win there as well.
- Improve VRAM oversubscription behavior when
  `VK_EXT_pageable_device_local_memory` is supported. (NVIDIA contribution, thanks!)
  This allows us to implement `Evict` and `MakeResident` APIs in a useful way.
  `VK_EXT_memory_priority` is also used for static priorities as a fallback.

### Features

- Add `VK_EXT_image_sliced_view_of_3d` to support sliced 3D UAVs.
- Improve DXR 1.1 support with `VK_EXT_pipeline_library_group_handles`.
- Implement `VK_EXT_fragment_shader_interlock`. Completes FL 12.1.
- Move to Vulkan 1.3 as minimum version.
- D3D11on12 interoperability interfaces are now supported.
  It is compatible with DXVK 2.2, which actually implements 11on12.

### Legacy swapchain removal

The old swapchain implementation is now gone.
DXVK 2.1 is required as we now share common code.
This means that there is no fallback for pre-2.1 DXVK versions or Wine DXGI anymore.

#### Native Linux swapchain support

The new swapchain can support Linux native surfaces.
The demo applications in `demos/` with functional swapchain now builds on Linux as well.

### Driver workarounds

- `KHR_present_wait` is currently disabled on NVIDIA drivers due to a bug that would occur on some PRIME setups.
  This is supposed to be fixed in the latest beta drivers, and this workaround will eventually be removed
  when we have a confirmed major version that fixes the issue.
- Workaround RADV bug causing memory bloat in shader caches. Can save several 100s of MBs of memory,
  which is important on certain memory hungry titles to avoid instability.
- Workaround NVIDIA bug with concurrent queue submissions using timeline semaphores.
  Fixed a bunch of inexplicable `Xid 109 CTX_SWITCH_TIMEOUT` errors in many different games.

### Bugfixes and game workarounds

Various bugfixes for games as usual. Listing individual games is becoming impractical at this point,
and it's best to refer to other sources for compatibility information with specific games.
As usual, a bunch of fixes in dxil-spirv to fix shader bugs.

### Misc

- On Wine, use `winevulkan.dll` rather than `vulkan-1.dll` if available.
  Works around some games that hook Vulkan despite using D3D12.
- Improve compatibility with games relying on certain AgilitySDK details.
- Improve build system compatibility with different `widl` versions.
- `VKD3D_CONFIG=dxr` now enables DXR 1.1 as well. `dxr11` is kept for compat.
- Fix HDR Metadata MinLuminance value.
- Add `VKD3D_LIMIT_TESS_FACTORS` to work around excessive tessellation. Enabled for Wo Long.
- (Developers) Improve debugging support with more detailed breadcrumb information.
- (Developers) Insert more actionable information in captures and logs.
- (Developers) Log directly to Wine when available. Makes `PROTON_LOG=1` more reliable.
- (Developers) Set thread names on Win32 build as well.
- (Developers) Use native Linux calling convention instead of `ms_abi`.

## 2.8

This release rolls up some significant new developments before the holidays.

## VK_EXT_descriptor_buffer support

This extension is significant in that it removes a ton of CPU overhead.
We already had most of this in place on RADV and Steam Deck,
but this will allow NVIDIA, Intel, Turnip, and other AMD driver implementations to hit the same optimal code paths.
GPU bound performance increases slightly since we can also remove some shader code that was required to workaround lack of descriptor buffers.

### New extension requirements

To support descriptor buffers in the code base, these features are now required instead of optional.
Note that these features are widely supported already and is not expected to cause any problems.
If an implementation could support v2.7, it will support v2.8.

- `VK_KHR_buffer_device_address`
- `VK_KHR_push_descriptor`

## Rewritten support for host accessible images

The entire API feature was rewritten from scratch to support more implementations and edge cases without
a lot of per-application hacks and workarounds.
As the most extreme example of weird API usage, Guardians of the Galaxy should (finally) run well on NVIDIA.

## Rewritten swap chain

To most users, this change should be transparent.

- Allow more precise control on latency and frame pacing with `VK_KHR_present_wait`.
  - mesa-git supports this along with NVIDIA.
  - `VKD3D_SWAPCHAIN_LATENCY_FRAMES=n` allows user to force a specific amount of latency.
  - Implementation of DXGI latency fences is now correct.
- Reduce CPU overhead on the main thread that presents to swap chain.
- Fixes a spurious hang in Hitman III where game relies on asynchronous present in order to not lock up.
- Win32 specific DXGI code is handled by DXVK. A DXVK build from Experimental or later is required for this to work.
  This allows a native Linux implementation of vkd3d-proton, including swap chain.
- When `VK_KHR_present_wait` is not supported, behavior should be 1:1 with old implementation.

NOTE: The old swapchain implementation is still in the repository, and is expected to be removed in the next release.
For now, `VKD3D_CONFIG=swapchain_legacy` can be used to triage any potential issues with the new one.

NOTE: A driver crash was observed on NVIDIA 525.x drivers when running in some PRIME configurations.
For now, we disable use of present_wait on these drivers.

### Fixes and workarounds

- Workaround GPU hangs in Spiderman Remastered: Miles Morales (same issue as the original).
- Fix rendering bug with gun damage in Borderlands 3 on RADV.
- Refactor how resizable BAR is used. GPUs with 4 GiB and lower will no longer attempt to use resizable BAR,
  which can avoid some out-of-memory situations.
- Fix GPU hang in Age of Empires IV.
- Fix some minor issues in mesh shader implementation.
- Fix some issues preventing RE: Village from booting on Arc.
- Some last minute frenzied fixes for Witcher 3 next-gen update.
  - All features except RT appears to work on RADV.
  - Hairworks is known to crash GPU on NVIDIA. More investigation is needed to root cause.
  - Some RT effects work on NVIDIA, others don't:
    - GI is reported to work.
    - AO crashes GPU. More investigation is needed to root cause.

#### Implement minor missing D3D12 features

An obscure feature was stubbed out and forgotten until now.
`ID3D12Device1::SetEventOnMultipleFenceCompletion()` is now implemented.

Also, implement SetEventOn(Multiple)FenceCompletion for shared D3D12 fences.
Fixes a regression in Gears 5 causing lockup on boot.

## 2.7

This release rolls up a massive amount of work since the Steam Deck launch in late February
with mostly features and fixes.

### Heightened driver requirements

Newer extensions are now required.

- `VK_KHR_dynamic_rendering`
- `VK_EXT_extended_dynamic_state`
- `VK_EXT_extended_dynamic_state2` (no optional features required)
- `VK_KHR_maintenance4`

`KHR_dynamic_rendering` in particular requires Mesa 22.0 or NVIDIA 510 series, which should have
propagated to distributions a long time ago at this point.

NOTE: Proton 7.0 stable series will stick to v2.6 to avoid the hard driver requirement bump.
Proton Experimental and any future stable beyond 7.0 will stick to v2.7 and later.

`KHR_dynamic_rendering` fixes many previously unsolvable issues, but it required a rewrite,
and it was deemed impractical to support both legacy and modern paths.

### Improved pipeline cache

v2.6 introduced support for pipeline libraries, but only for games which made correct use of the D3D12 API.
To improve the situation across the board,
vkd3d-proton now implements an internal "magic" disk cache to enable SPIR-V caching for all games.
It is possible to disable the magic cache and let applications manage the ID3D12PipelineLibrary itself if desired.

To further reduce on-disk footprint of the magic cache, we also make use of `VK_EXT_shader_module_identifier`
to reduce the vkd3d-proton cache by >95%, since there is no need to store actual SPIR-V data on-disk.

### Optimizations

Mostly a lot of minor things this release.

- Slightly improve GPU performance for depth render passes.
- Improve GPU performance for certain floating-point images where UAV usage was enabled.
- Improve GPU performance for certain use cases of WriteBufferImmediate().
- Improve GPU performance for certain access patterns of root descriptors.
- Improve GPU performance for back-to-back buffer-image copies.
- Improve GPU performance when allocating large zero-cleared resources and heaps.
- Misc things here and there to reduce overhead.

### New D3D12 features

#### Mesh shaders

`VK_EXT_mesh_shader` is required for this. Directly compatible with D3D12.

#### Advanced ExecuteIndirect

Uses `VK_NV_device_generated_commands`. Supported by both RADV and NVIDIA. Allows Halo Infinite to run.

#### DXR 1.1

Implement some missing features from DXR 1.1:

- AddToStateObject()
- ExecuteIndirect trace rays
- Various complex RTPSO features
- DXIL subobject parsing
- Misc query features

With these fixes in place, e.g. Cyberpunk 2077 DXR works. `VK_KHR_raytracing_maintenance1` is required for some features.

NOTE: `VKD3D_CONFIG=dxr11` is required to enable DXR 1.1 for now.

#### Shared resources

Basic shared resources and fences are now supported when running on Proton. Allows interop with DXVK.
Special thanks to Derek Lesho (@Guy1524) for implementation.

#### SV_Barycentrics

SM 6.1 barycentrics are now exposed through `VK_KHR_fragment_shader_barycentric`.

#### Preliminary HDR support

vkd3d-proton can take advantage of HDR now, assuming the system itself supports it.

### Game fixes and workarounds

- Fix random GPU hangs in Hitman 3.
- Fix crash in Redout 2.
- Fix random GPU hang in F1 2021.
- Fix random flicker in Guardians of the Galaxy.
- Update some API checks required by latest AgilitySDK runtime features. Fix crash in F1 2022.
- Add various workarounds for game bugs in Halo Infinite.
- Add workaround for amdgpu kernel issue for certain games using imported host memory and multiple Vulkan devices.
- Workaround glitched rendering in F1 2020 due to game bug.
- Workaround certain games that violate placed resource API w.r.t. subresource initialization.
  Spiderman Remastered and Lost Judgment are affected. More games will likely surface.

### DXIL support

Countless bug fixes for games released since last release. Too many to enumerate individually.

### Misc

- Improve compatibility with Intel ANV driver.
- Improve correctness of GetFrameLatencyWaitableObject().
- Add BLOB PIX decoding.
- Improve stability when minimizing and alt-tabbing in and out of fullscreen in some games.
- Preparation for MIT re-license is underway.

### Stronger debugging facilities

- For developers and power users, a breadcrumbs functionality is added to greatly aid GPU hang debugging.
  Requires either `VK_AMD_buffer_marker` or `VK_NV_device_diagnostic_checkpoints`.
- When capturing with RenderDoc, cached host memory is enabled by default to speed up capture and improve stability.
- Improve shader replacement system ease-of-use.

## 2.6

It has been a long while since 2.5, and this release rolls up a lot of fixes, features and optimizations.

### Fixes

- Fix black screen rendering bug in Horizon Zero Dawn after latest game updates.
- Fix crashes on startup in Final Fantasy VII: Remake and Warframe.
- Fix crashes in Guardians of the Galaxy when interacting with certain game objects.
- Fix hang on game shutdown in Elden Ring.
- Fix broken geometry rendering in Age of Empires: IV.

### Optimization

- Improve generated shader code for vectorized load-store operations in DXIL.
- Greatly reduce CPU overhead for descriptor copy operations,
  which is a key contributor to CPU overhead in D3D12.

### Features

#### Pipeline library rewrite

Support D3D12 pipeline libraries better where we can now also cache
generated SPIR-V from DXBC/DXIL.
Massively reduces subsequent load times in Monster Hunter: Rise,
and helps other titles like Guardian of the Galaxy and Elden Ring.
Also lays the groundwork for internal driver caches down the line for games which do not use this API.
Also, deduplicates binary blobs for reduced disk size requirements.

#### Shader models

Shader model 6.6 is now fully implemented. This includes support for:
- ResourceDescriptorHeap[] direct access
- 64-bit atomics
- IsHelperLane()
- Compute shader derivatives
- WaveSize attribute
- Packed math intrinsics

#### Minor features

- Handle API feature MinResourceLODClamp correctly if `VK_EXT_image_view_min_lod` is supported.
- Expose CastFullyTypedFormat feature.
- Expose some advanced shader features on Intel related to UAV formats (`VK_KHR_format_feature_flags2`).
- Support COLOR -> STENCIL copies.

### Workarounds

- Workaround DEATHLOOP not emitting synchronization commands correctly. Fixes menu flicker on RADV.
- Workaround quirky API usage in Elden Ring. Removes many kinds of stutter and chug when traversing the scenery.
- Workaround certain environments failing to create Vulkan device if some `VK_NVX_*` extensions are enabled.
- Workaround glitched foliage rendering in Horizon Zero Dawn after latest game updates.
- Workaround some questionable UE4 shaders causing glitched rendering on RADV.

### Note on future Vulkan driver requirements

2.6 is expected to be the last vkd3d-proton release before we require some newer Vulkan extensions.
`VK_KHR_dynamic_rendering` and `VK_EXT_extended_dynamic_state`
(and likely `dynamic_state_2` as well) will be required.

`VK_KHR_dynamic_rendering` in particular requires up-to-date drivers and the legacy render pass path
will be abandoned in favor of it. Supporting both paths at the same time is not practical.
Moving to `VK_KHR_dynamic_rendering` allows us to fix some critical flaws with the legacy API
which caused potential shader compilation stutters and extra CPU overhead.

## 2.5

This is a release with a little bit of everything!

### Features

#### DXR progress

DXR has seen significant work in the background.

- DXR 1.1 is now experimentally exposed. It can be enabled with `VKD3D_CONFIG=dxr11`.
  Note that DXR 1.1 cannot be fully implemented in `VK_KHR_ray_tracing`'s current form, in particular
  DispatchRays() indirect is not compatible yet,
  although we have not observed a game which requires this API feature.
- DXR 1.1 inline raytracing support is fully implemented.
- DXR 1.0 support is more or less feature complete.
  Some weird edge cases remain, but will likely not be implemented unless required by a game.
  `VKD3D_CONFIG=dxr` will eventually be dropped when it matures.

Some new DXR games are starting to come alive, especially with DXR 1.1 enabled,
but there are significant bugs as well that we currently cannot easily debug.
Some experimental results on NVIDIA:

- **Control** - already worked
- **DEATHLOOP** - appears to work correctly
- **Cyberpunk 2077** - DXR can be enabled, but GPU timeouts
- **World of Warcraft** - according to a user, it works, but we have not confirmed ourselves
- **Metro Exodus: Enhanced Edition** -
    gets ingame and appears to work? Not sure if it looks correct.
    Heavy CPU stutter for some reason ...
- **Metro Exodus** (original release) - GPU timeouts when enabling DXR
- **Resident Evil: Village** - Appears to work, but the visual difference is subtle.

It's worth experimenting with these and others.
DXR is incredibly complicated, so expect bugs.
From here, DXR support is mostly a case of stamping out issues one by one.

#### NVIDIA DLSS

NVIDIA contributed integration APIs in vkd3d-proton which enables DLSS support in D3D12 titles in Proton.
See Proton documentation for how to enable NvAPI support.

#### Shader models

A fair bit of work went into DXIL translation support to catch up with native drivers.

- Shader model 6.5 is exposed.
  Shader model 6.6 should be straight forward once that becomes relevant.
- Shader model 6.4 implementation takes advantage of `VK_KHR_shader_integer_dot_product` when supported.
- Proper fallback for FP16 math on GPUs which do not expose native FP16 support (Polaris, Pascal).
  Notably fixes AMD FSR shaders in Resident Evil: Village (and others).
- Shader model 6.1 SV_Barycentric support implemented (NVIDIA only for now).
- Support shader model 6.2 FP32 denorm control.

### Performance

Resizable BAR can improve GPU performance about 10-15% in the best case, depends a lot on the game.
Horizon Zero Dawn and Death Stranding in particular improve massively with this change.

By default, vkd3d-proton will now take advantage of PCI-e BAR memory types through heuristics
as D3D12 does not expose direct support for resizable BAR, and native D3D12 drivers are known to use heuristics as well.
Without resizable BAR enabled in BIOS/vBIOS, we only get 256 MiB which can help performance,
but many games will improve performance even more
when we are allowed to use more than that.
There is an upper limit for how much VRAM is dedicated to this purpose.
We also added `VKD3D_CONFIG=no_upload_hvv` to disable all uses of PCI-e BAR memory.

Other performance improvements:

- Avoid redundant descriptor update work in certain scenarios (NVIDIA contribution).
- Minor tweaks here and there to reduce CPU overhead.

### Fixes and workarounds

- Fix behavior for swap chain presentation latency HANDLE. Fixes spurious deadlocks in some cases.
- Fix many issues related to depth-stencil handling, which fixed various issues in DEATHLOOP, F1 2021, WRC 10.
- Fix DIRT 5 rendering issues and crashes. Should be fully playable now.
- Fix some Diablo II Resurrected rendering issues.
- Workaround shader bugs in Psychonauts 2.
- Workaround some Unreal Engine 4 shader bugs which multiple titles trigger.
- Fix some stability issues when VRAM is exhausted on NVIDIA.
- Fix CPU crash in boot-up sequence of Far Cry 6 (game is still kinda buggy though, but gets in-game).
- Fix various bugs with host visible images. Fixes DEATHLOOP.
- Fix various DXIL conversion bugs.
- Add Invariant geometry workarounds for specific games which require it.
- Fix how d3d12.dll exports symbols to be more in line with MSVC.
- Fix some edge cases in bitfield instructions.
- Work around extreme CPU memory bloat on the specific NVIDIA driver versions which had this bug.
- Fix regression in Evil Genius 2: World Domination.
- Fix crashes in Hitman 3.
- Fix terrain rendering in Anno 1800.
- Various correctness and crash fixes.

## 2.4

This is a release which focuses on performance and bug-fixes.

### Performance

- Improve swapchain latency and frame pacing by up to one frame.
- Optimize lookup of format info.
- Avoid potential pipeline compilation stutter in certain scenarios.
- Rewrite how we handle image layouts for color and depth-stencil targets.
  Allows us to remove a lot of dumb
  barriers giving significant GPU-bound performance improvements.
  ~15%-20% GPU bound uplift in Horizon Zero Dawn,
  ~10% in Death Stranding,
  and 5%-10% improvements in many other titles.

### Features

- Enable support for sparse 3D textures (tiled resources tier 3).

### Bug fixes and workarounds

- Various bug fixes in DXIL.
- Fix weird bug where sun would pop through walls in RE: Village.
- Workaround game bug in Cyberpunk 2077 where certain locales would render a black screen.
- Fix various bugs (in benchmark and in vkd3d-proton) allowing GravityMark to run.
- Improve robustness against certain app bugs related to NULL descriptors.
- Fix bug with constant FP64 vector handling in DXBC.
- Fix bug where Cyberpunk 2077 inventory screen could spuriously hang GPU on RADV.
- Add workaround for Necromunda: Hired Gun where character models would render random garbage on RADV.
- Fix bug in Necromunda: Hired Gun causing random screen flicker.
- Fix windowed mode tracking when leaving fullscreen. Fix Alt-Tab handling in Horizon Zero Dawn.
- Temporary workaround for SRV ResourceMinLODClamp. Fix black ground rendering in DIRT 5.
  The overbright HDR rendering in DIRT 5 sadly persists however :(
- Implement fallback maximum swapchain latency correctly.

### Development features

Various features which are useful for developers were added to aid debugging.

- Descriptor QA can instrument shaders in runtime for GPU-assisted validation.
  Performance is good enough (> 40 FPS) that games are actually playable in this mode.
  See README for details.
- Allow forcing off CONCURRENT queue, and using EXCLUSIVE queue.
  Not valid, but can be useful as a speed hack on Polaris when `single_queue` is not an option
  and for testing driver behavior differences.

## 2.3.1

This is a minor bugfix release to address some issues solved shortly after the last release.

### Fixes

- Improved support for older Wine and Vulkan Loader versions.
- Fix blocky shadows in Horizon Zero Dawn.
- Fix the install script failing on Wine installs not built with upstream vkd3d.
- Fix minor dxil translation issues.

## 2.3

This release adds support for more D3D12 features and greatly improves GPU bound performance
in many scenarios.

### Features

#### Early DXR 1.0 support

`VK_KHR_raytracing` is used to enable cross-vendor ray-tracing support.
The implementation is WIP, but it is good enough to run some real content.

As of writing, only the NVIDIA driver works correctly.
It is expected AMD RDNA2 GPUs will work when working drivers are available
(amdgpu-pro 21.10 is known to not work).

Games which are expected to work include:
- Control (appears to be fully working)
- Ghostrunner (seems to work, not exhaustively tested)

To enable DXR support, `VKD3D_CONFIG=dxr %command%` should be used when launching game.
Certain games may be unstable if DXR is enabled by default.

#### Conservative rasterization

Full support (tier 3) for conservative rasterization was added.

#### Variable rate shading

Full support (tier 2) for variable rate shading was added.

#### Command list bundles

Allows Kingdom Hearts remaster to get past the errors, unsure if game fully works yet.

#### Write Watch and APITrace

Support for `D3D12_HEAP_FLAG_ALLOW_WRITE_WATCH` has been added.
This means [APITraces](https://github.com/Joshua-Ashton/apitrace/releases) of titles can now be captured.

### Performance

- Improve GPU bound performance in RE2 by up to 20% on NVIDIA.
- Enable async compute queues. Greatly improves GPU performance and frame pacing in many titles.
  Horizon Zero Dawn and Death Stranding see exceptional gains with this fix,
  due to how the engines work. GPU utilization should now reach ~100%.
  For best results, AMD Navi+ GPUs are recommended, but Polaris and earlier still
  see great results. It is possible to disable this path, if for whatever reason
  multiple queues are causing issues. See README.
- Optimize bindless constant buffer GPU-bound performance on NVIDIA if certain API code paths are used.
- Optimize sparse binding CPU overhead.
- `TRACE` logging calls are disabled by default on release builds.

### Fixes and workarounds

- Fix various DXIL bugs.
- Be more robust against broken pipeline creation API calls.
  Avoids driver crashes in Forza Horizon 4.
- Workaround some buggy shaders in F1 2020.
- Fix bugs if depth bounds test is used in certain ways.
- Fix a read out-of-bounds in `UpdateTileMappings`.
- Fix `SV_ClipDistance` and `SV_CullDistance` in Hull Shaders.

## 2.2

This release is mostly a maintenance release which fixes bugs and regressions.
It also unblocks significant future feature development.

### Workaround removals

- Replace old `force_bindless_texel_buffer` workaround with
  a more correct and performant implementation.
  Death Stranding and Cyberpunk 2077 (and probably other games as well) do the right thing by default without the hack now.
- Remove old workaround `disable_query_optimization` for occlusion queries which was enabled for AC: Valhalla,
  and is now replaced by a correct and efficient implementation.

#### Cyberpunk 2077 status
From recent testing on our end, it is unknown at this time if `VK_VALVE_mutable_descriptor_type` is still required for
Cyberpunk 2077. Manual testing hasn't been able to trigger a GPU hang.
The memory allocation rewrite in 2.2 can plausibly work around some of the bugs that `VK_VALVE_mutable_descriptor_type` fixed by accident.
The bugs in question could also have been fixed since release day, but we cannot prove this since the bug is completely random in nature.

### Regression fixes

- Fix regression in Horizon Zero Dawn for screen space reflections on water surfaces.

### Stability fixes

- Greatly improve stability on Polaris or older cards for certain titles.
  Crashes which used to happen in Horizon Zero Dawn and Death Stranding seem to have disappeared
  after the memory allocation rewrite.
  GPU memory usage should decrease on these cards as well.
- DIRT 5 can get in-game now due to DXIL fixes, but is not yet playable.

### New features

- Add support for Variable Rate Shading tier 1.

### Future development

DXR is not yet supported, but has seen a fair bit of background work.

- Basic DXR pipelines can be created successfully.
- Memory allocation rewrite in 2.2 unblocks further DXR development.

## 2.1

This release fixes various bugs (mostly workarounds) and improves GPU-bound performance.

New games added to "expected to work" list:
 - The Division (was working already in 2.0, but missing from list)
 - AC: Valhalla (*)

(*): Game requires full D3D12 sparse texture support to work.
Currently only works on NVIDIA drivers.
RADV status remains unknown until support for this feature lands in Mesa.

New games added to "kinda works, but expect a lot of jank" list:
 - Cyberpunk 2077 (**)

(**): Currently only runs correctly on AMD hardware with RADV and `VK_VALVE_mutable_descriptor_type`.
As of game version 1.03, this requires the latest Mesa Git build.
The game has some fatal bugs where it relies on undefined behavior with descriptor management
which this extension works around by accident.
The game will start and run on NVIDIA, but just like what happens without the extension on AMD,
the GPU will randomly hang, making the game effectively unplayable.
A game update to fix this bug would likely make the game playable on NVIDIA as well.
Game version 1.04 changed some behavior, and support for this game will likely fluctuate over time as future patches come in.

Bug fixes and workarounds:
 - Fix various implementation bugs which caused AC: Valhalla to not work.
 - Work around game bug in Death Stranding where accessing map could cause corrupt rendering.
   (Several games appear to have the same kind of application bug.)
 - Fix corrupt textures in Horizon Zero Dawn benchmark.
 - Fix SM 6.0 wave-op detection for Horizon Zero Dawn and DIRT 5.
 - Work around GPU hangs in certain situations where games do not use D3D12 correctly,
   but native D3D12 drivers just render wrong results rather than hang the system.
 - Fix invalid SPIR-V generated by FP64 code.
 - Fix crash with minimized windows in certain cases.

Performance:
 - ~15% GPU-bound uplift in Ghostrunner. Might help UE4 titles in general.
 - Slightly improve GPU bound performance when fully GPU bound on both AMD and NVIDIA.
 - Slightly improve GPU bound performance on RADV in various titles.
 - Reduce multi-threaded CPU overhead for certain D3D12 API usage patterns.
 - Add support for `VK_VALVE_mutable_descriptor_type` which
   improves CPU overhead, memory bloat, and avoids potential memory management thrashing on RADV.
   Also avoids GPU hangs in certain situations where games misuse the D3D12 API.

Misc:
 - Implement `DXGI_PRESENT_TEST`.
 - Fix log spam when `DXGI_PRESENT_ALLOW_TEARING` is used.

## 2.0

This initial release supports D3D12 Feature Level 12.0 and Shader Model 6.0 (DXIL).

Games expected to work include:

 - Control
 - Death Stranding
 - Devil May Cry 5
 - Ghostrunner
 - Horizon Zero Dawn
 - Metro Exodus
 - Monster Hunter World
 - Resident Evil 2 / 3

Please refer to the README for supported driver versions.

