Flutter Impeller
ahb_texture_source_vk.cc
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
6 
11 
12 namespace impeller {
13 
14 using AHBProperties = vk::StructureChain<
15  // For VK_ANDROID_external_memory_android_hardware_buffer
16  vk::AndroidHardwareBufferPropertiesANDROID,
17  // For VK_ANDROID_external_memory_android_hardware_buffer
18  vk::AndroidHardwareBufferFormatPropertiesANDROID>;
19 
21  const vk::Device& device,
22  const AHBProperties& ahb_props,
23  const AHardwareBuffer_Desc& ahb_desc) {
24  const auto& ahb_format =
25  ahb_props.get<vk::AndroidHardwareBufferFormatPropertiesANDROID>();
26 
27  vk::StructureChain<vk::ImageCreateInfo,
28  // For VK_KHR_external_memory
29  vk::ExternalMemoryImageCreateInfo,
30  // For VK_ANDROID_external_memory_android_hardware_buffer
31  vk::ExternalFormatANDROID>
32  image_chain;
33 
34  auto& image_info = image_chain.get<vk::ImageCreateInfo>();
35 
36  vk::ImageUsageFlags image_usage_flags;
37  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE) {
38  image_usage_flags |= vk::ImageUsageFlagBits::eSampled;
39  }
40  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_FRAMEBUFFER) {
41  image_usage_flags |= vk::ImageUsageFlagBits::eColorAttachment;
42  }
43  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_COMPOSER_OVERLAY) {
44  image_usage_flags |= vk::ImageUsageFlagBits::eColorAttachment;
45  image_usage_flags |= vk::ImageUsageFlagBits::eInputAttachment;
46  image_usage_flags |= vk::ImageUsageFlagBits::eTransferDst;
47  }
48 
49  vk::ImageCreateFlags image_create_flags;
50  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_PROTECTED_CONTENT) {
51  image_create_flags |= vk::ImageCreateFlagBits::eProtected;
52  }
53  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_CUBE_MAP) {
54  image_create_flags |= vk::ImageCreateFlagBits::eCubeCompatible;
55  }
56 
57  image_info.imageType = vk::ImageType::e2D;
58  image_info.format = ahb_format.format;
59  image_info.extent.width = ahb_desc.width;
60  image_info.extent.height = ahb_desc.height;
61  image_info.extent.depth = 1;
62  image_info.mipLevels =
63  (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE)
64  ? ISize{ahb_desc.width, ahb_desc.height}.MipCount()
65  : 1u;
66  image_info.arrayLayers = ahb_desc.layers;
67  image_info.samples = vk::SampleCountFlagBits::e1;
68  image_info.tiling = vk::ImageTiling::eOptimal;
69  image_info.usage = image_usage_flags;
70  image_info.flags = image_create_flags;
71  image_info.sharingMode = vk::SharingMode::eExclusive;
72  image_info.initialLayout = vk::ImageLayout::eUndefined;
73 
74  image_chain.get<vk::ExternalMemoryImageCreateInfo>().handleTypes =
75  vk::ExternalMemoryHandleTypeFlagBits::eAndroidHardwareBufferANDROID;
76 
77  // If the format isn't natively supported by Vulkan (i.e, be a part of the
78  // base vkFormat enum), an untyped "external format" must be specified when
79  // creating the image and the image views. Usually includes YUV formats.
80  if (ahb_format.format == vk::Format::eUndefined) {
81  image_chain.get<vk::ExternalFormatANDROID>().externalFormat =
82  ahb_format.externalFormat;
83  } else {
84  image_chain.unlink<vk::ExternalFormatANDROID>();
85  }
86 
87  auto image = device.createImageUnique(image_chain.get());
88  if (image.result != vk::Result::eSuccess) {
89  VALIDATION_LOG << "Could not create image for external buffer: "
90  << vk::to_string(image.result);
91  return {};
92  }
93 
94  return std::move(image.value);
95 }
96 
97 static vk::UniqueDeviceMemory ImportVKDeviceMemoryFromAndroidHarwareBuffer(
98  const vk::Device& device,
99  const vk::PhysicalDevice& physical_device,
100  const vk::Image& image,
101  struct AHardwareBuffer* hardware_buffer,
102  const AHBProperties& ahb_props) {
103  vk::PhysicalDeviceMemoryProperties memory_properties;
104  physical_device.getMemoryProperties(&memory_properties);
105  int memory_type_index = AllocatorVK::FindMemoryTypeIndex(
106  ahb_props.get().memoryTypeBits, memory_properties);
107  if (memory_type_index < 0) {
108  VALIDATION_LOG << "Could not find memory type of external image.";
109  return {};
110  }
111 
112  vk::StructureChain<vk::MemoryAllocateInfo,
113  // Core in 1.1
114  vk::MemoryDedicatedAllocateInfo,
115  // For VK_ANDROID_external_memory_android_hardware_buffer
116  vk::ImportAndroidHardwareBufferInfoANDROID>
117  memory_chain;
118 
119  auto& mem_alloc_info = memory_chain.get<vk::MemoryAllocateInfo>();
120  mem_alloc_info.allocationSize = ahb_props.get().allocationSize;
121  mem_alloc_info.memoryTypeIndex = memory_type_index;
122 
123  auto& dedicated_alloc_info =
124  memory_chain.get<vk::MemoryDedicatedAllocateInfo>();
125  dedicated_alloc_info.image = image;
126 
127  auto& ahb_import_info =
128  memory_chain.get<vk::ImportAndroidHardwareBufferInfoANDROID>();
129  ahb_import_info.buffer = hardware_buffer;
130 
131  auto device_memory = device.allocateMemoryUnique(memory_chain.get());
132  if (device_memory.result != vk::Result::eSuccess) {
133  VALIDATION_LOG << "Could not allocate device memory for external image : "
134  << vk::to_string(device_memory.result);
135  return {};
136  }
137 
138  return std::move(device_memory.value);
139 }
140 
141 static std::shared_ptr<YUVConversionVK> CreateYUVConversion(
142  const ContextVK& context,
143  const AHBProperties& ahb_props) {
144  YUVConversionDescriptorVK conversion_chain;
145 
146  const auto& ahb_format =
147  ahb_props.get<vk::AndroidHardwareBufferFormatPropertiesANDROID>();
148 
149  auto& conversion_info = conversion_chain.get();
150 
151  conversion_info.format = ahb_format.format;
152  conversion_info.ycbcrModel = ahb_format.suggestedYcbcrModel;
153  conversion_info.ycbcrRange = ahb_format.suggestedYcbcrRange;
154  conversion_info.components = ahb_format.samplerYcbcrConversionComponents;
155  conversion_info.xChromaOffset = ahb_format.suggestedXChromaOffset;
156  conversion_info.yChromaOffset = ahb_format.suggestedYChromaOffset;
157  // If the potential format features of the sampler Y′CBCR conversion do not
158  // support VK_FORMAT_FEATURE_SAMPLED_IMAGE_YCBCR_CONVERSION_LINEAR_FILTER_BIT,
159  // chromaFilter must not be VK_FILTER_LINEAR.
160  //
161  // Since we are not checking, let's just default to a safe value.
162  conversion_info.chromaFilter = vk::Filter::eNearest;
163  conversion_info.forceExplicitReconstruction = false;
164 
165  if (conversion_info.format == vk::Format::eUndefined) {
166  auto& external_format = conversion_chain.get<vk::ExternalFormatANDROID>();
167  external_format.externalFormat = ahb_format.externalFormat;
168  } else {
169  conversion_chain.unlink<vk::ExternalFormatANDROID>();
170  }
171 
172  return context.GetYUVConversionLibrary()->GetConversion(conversion_chain);
173 }
174 
175 static vk::UniqueImageView CreateVKImageView(
176  const vk::Device& device,
177  const vk::Image& image,
178  const vk::SamplerYcbcrConversion& yuv_conversion,
179  const AHBProperties& ahb_props,
180  const AHardwareBuffer_Desc& ahb_desc) {
181  const auto& ahb_format =
182  ahb_props.get<vk::AndroidHardwareBufferFormatPropertiesANDROID>();
183 
184  vk::StructureChain<vk::ImageViewCreateInfo,
185  // Core in 1.1
186  vk::SamplerYcbcrConversionInfo>
187  view_chain;
188 
189  auto& view_info = view_chain.get();
190 
191  view_info.image = image;
192  view_info.viewType = vk::ImageViewType::e2D;
193  view_info.format = ahb_format.format;
194  view_info.subresourceRange.aspectMask = vk::ImageAspectFlagBits::eColor;
195  view_info.subresourceRange.baseMipLevel = 0u;
196  view_info.subresourceRange.baseArrayLayer = 0u;
197  view_info.subresourceRange.levelCount =
198  (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE)
199  ? ISize{ahb_desc.width, ahb_desc.height}.MipCount()
200  : 1u;
201  view_info.subresourceRange.layerCount = ahb_desc.layers;
202 
203  // We need a custom YUV conversion only if we don't recognize the format.
204  if (view_info.format == vk::Format::eUndefined) {
205  view_chain.get<vk::SamplerYcbcrConversionInfo>().conversion =
206  yuv_conversion;
207  } else {
208  view_chain.unlink<vk::SamplerYcbcrConversionInfo>();
209  }
210 
211  auto image_view = device.createImageViewUnique(view_info);
212  if (image_view.result != vk::Result::eSuccess) {
213  VALIDATION_LOG << "Could not create external image view: "
214  << vk::to_string(image_view.result);
215  return {};
216  }
217 
218  return std::move(image_view.value);
219 }
220 
221 static PixelFormat ToPixelFormat(AHardwareBuffer_Format format) {
222  switch (format) {
223  case AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM:
225  case AHARDWAREBUFFER_FORMAT_R16G16B16A16_FLOAT:
227  case AHARDWAREBUFFER_FORMAT_D24_UNORM_S8_UINT:
229  case AHARDWAREBUFFER_FORMAT_D32_FLOAT_S8_UINT:
231  case AHARDWAREBUFFER_FORMAT_S8_UINT:
232  return PixelFormat::kS8UInt;
233  case AHARDWAREBUFFER_FORMAT_R8_UNORM:
235  case AHARDWAREBUFFER_FORMAT_R10G10B10A10_UNORM:
236  case AHARDWAREBUFFER_FORMAT_R16G16_UINT:
237  case AHARDWAREBUFFER_FORMAT_D32_FLOAT:
238  case AHARDWAREBUFFER_FORMAT_R16_UINT:
239  case AHARDWAREBUFFER_FORMAT_D24_UNORM:
240  case AHARDWAREBUFFER_FORMAT_Y8Cb8Cr8_420:
241  case AHARDWAREBUFFER_FORMAT_YCbCr_P010:
242  case AHARDWAREBUFFER_FORMAT_BLOB:
243  case AHARDWAREBUFFER_FORMAT_R10G10B10A2_UNORM:
244  case AHARDWAREBUFFER_FORMAT_R5G6B5_UNORM:
245  case AHARDWAREBUFFER_FORMAT_R8G8B8_UNORM:
246  case AHARDWAREBUFFER_FORMAT_D16_UNORM:
247  case AHARDWAREBUFFER_FORMAT_R8G8B8X8_UNORM:
248  // Not understood by the rest of Impeller. Use a placeholder but create
249  // the native image and image views using the right external format.
250  break;
251  }
253 }
254 
255 static TextureType ToTextureType(const AHardwareBuffer_Desc& ahb_desc) {
256  if (ahb_desc.layers == 1u) {
258  }
259  if (ahb_desc.layers % 6u == 0 &&
260  (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_CUBE_MAP)) {
262  }
263  // Our texture types seem to understand external OES textures. Should these be
264  // wired up instead?
266 }
267 
269  const AHardwareBuffer_Desc& ahb_desc) {
270  const auto ahb_size = ISize{ahb_desc.width, ahb_desc.height};
271  TextureDescriptor desc;
272  // We are not going to touch hardware buffers on the CPU or use them as
273  // transient attachments. Just treat them as device private.
275  desc.format =
276  ToPixelFormat(static_cast<AHardwareBuffer_Format>(ahb_desc.format));
277  desc.size = ahb_size;
278  desc.type = ToTextureType(ahb_desc);
281  desc.mip_count = (ahb_desc.usage & AHARDWAREBUFFER_USAGE_GPU_MIPMAP_COMPLETE)
282  ? ahb_size.MipCount()
283  : 1u;
284  if (ahb_desc.usage & AHARDWAREBUFFER_USAGE_COMPOSER_OVERLAY) {
286  }
287  return desc;
288 }
289 
291  const std::shared_ptr<Context>& p_context,
292  struct AHardwareBuffer* ahb,
293  const AHardwareBuffer_Desc& ahb_desc)
294  : TextureSourceVK(ToTextureDescriptor(ahb_desc)) {
295  if (!p_context) {
296  return;
297  }
298 
299  const auto& context = ContextVK::Cast(*p_context);
300 
301  const auto& device = context.GetDevice();
302  const auto& physical_device = context.GetPhysicalDevice();
303 
304  AHBProperties ahb_props;
305 
306  if (device.getAndroidHardwareBufferPropertiesANDROID(ahb, &ahb_props.get()) !=
307  vk::Result::eSuccess) {
308  VALIDATION_LOG << "Could not determine properties of the Android hardware "
309  "buffer.";
310  return;
311  }
312 
313  const auto& ahb_format =
314  ahb_props.get<vk::AndroidHardwareBufferFormatPropertiesANDROID>();
315 
316  // Create an image to refer to our external image.
317  auto image =
318  CreateVKImageWrapperForAndroidHarwareBuffer(device, ahb_props, ahb_desc);
319  if (!image) {
320  return;
321  }
322 
323  // Create a device memory allocation to refer to our external image.
325  device, physical_device, image.get(), ahb, ahb_props);
326  if (!device_memory) {
327  return;
328  }
329 
330  // Bind the image to the image memory.
331  if (auto result = device.bindImageMemory(image.get(), device_memory.get(), 0);
332  result != vk::Result::eSuccess) {
333  VALIDATION_LOG << "Could not bind external device memory to image : "
334  << vk::to_string(result);
335  return;
336  }
337 
338  // Figure out how to perform YUV conversions.
339  auto yuv_conversion = CreateYUVConversion(context, ahb_props);
340  if (!yuv_conversion || !yuv_conversion->IsValid()) {
341  return;
342  }
343 
344  // Create image view for the newly created image.
345  auto image_view = CreateVKImageView(device, //
346  image.get(), //
347  yuv_conversion->GetConversion(), //
348  ahb_props, //
349  ahb_desc //
350  );
351  if (!image_view) {
352  return;
353  }
354 
355  needs_yuv_conversion_ = ahb_format.format == vk::Format::eUndefined;
356  device_memory_ = std::move(device_memory);
357  image_ = std::move(image);
358  yuv_conversion_ = std::move(yuv_conversion);
359  image_view_ = std::move(image_view);
360 
361 #ifdef IMPELLER_DEBUG
362  context.SetDebugName(device_memory_.get(), "AHB Device Memory");
363  context.SetDebugName(image_.get(), "AHB Image");
364  context.SetDebugName(yuv_conversion_->GetConversion(), "AHB YUV Conversion");
365  context.SetDebugName(image_view_.get(), "AHB ImageView");
366 #endif // IMPELLER_DEBUG
367 
368  is_valid_ = true;
369 }
370 
372  const std::shared_ptr<Context>& context,
373  std::unique_ptr<android::HardwareBuffer> backing_store,
374  bool is_swapchain_image)
375  : AHBTextureSourceVK(context,
376  backing_store->GetHandle(),
377  backing_store->GetAndroidDescriptor()) {
378  backing_store_ = std::move(backing_store);
379  is_swapchain_image_ = is_swapchain_image;
380 }
381 
382 // |TextureSourceVK|
384 
386  return is_valid_;
387 }
388 
389 // |TextureSourceVK|
390 vk::Image AHBTextureSourceVK::GetImage() const {
391  return image_.get();
392 }
393 
394 // |TextureSourceVK|
395 vk::ImageView AHBTextureSourceVK::GetImageView() const {
396  return image_view_.get();
397 }
398 
399 // |TextureSourceVK|
401  return image_view_.get();
402 }
403 
404 // |TextureSourceVK|
406  return is_swapchain_image_;
407 }
408 
409 // |TextureSourceVK|
410 std::shared_ptr<YUVConversionVK> AHBTextureSourceVK::GetYUVConversion() const {
411  return needs_yuv_conversion_ ? yuv_conversion_ : nullptr;
412 }
413 
415  return backing_store_.get();
416 }
417 
418 } // namespace impeller
impeller::AHBTextureSourceVK::GetBackingStore
const android::HardwareBuffer * GetBackingStore() const
Definition: ahb_texture_source_vk.cc:414
impeller::PixelFormat::kS8UInt
@ kS8UInt
impeller::AllocatorVK::FindMemoryTypeIndex
static int32_t FindMemoryTypeIndex(uint32_t memory_type_bits_requirement, vk::PhysicalDeviceMemoryProperties &memory_properties)
Select a matching memory type for the given [memory_type_bits_requirement], or -1 if none is found.
Definition: allocator_vk.cc:173
impeller::TextureSourceVK
Abstract base class that represents a vkImage and an vkImageView.
Definition: texture_source_vk.h:28
impeller::AHBTextureSourceVK::IsValid
bool IsValid() const
Definition: ahb_texture_source_vk.cc:385
impeller::AHBTextureSourceVK::AHBTextureSourceVK
AHBTextureSourceVK(const std::shared_ptr< Context > &context, struct AHardwareBuffer *hardware_buffer, const AHardwareBuffer_Desc &hardware_buffer_desc)
Definition: ahb_texture_source_vk.cc:290
allocator_vk.h
impeller::AHBTextureSourceVK::~AHBTextureSourceVK
~AHBTextureSourceVK() override
external_format
GLenum external_format
Definition: blit_command_gles.cc:125
impeller::PixelFormat::kR8UNormInt
@ kR8UNormInt
impeller::AHBTextureSourceVK::GetImageView
vk::ImageView GetImageView() const override
Retrieve the image view used for sampling/blitting/compute with this texture source.
Definition: ahb_texture_source_vk.cc:395
texture_source_vk.h
impeller::TextureDescriptor::format
PixelFormat format
Definition: texture_descriptor.h:41
impeller::PixelFormat::kR8G8B8A8UNormInt
@ kR8G8B8A8UNormInt
impeller::TextureType
TextureType
Definition: formats.h:262
impeller::TextureDescriptor::mip_count
size_t mip_count
Definition: texture_descriptor.h:43
yuv_conversion_library_vk.h
impeller::TextureUsage::kRenderTarget
@ kRenderTarget
impeller::CreateVKImageWrapperForAndroidHarwareBuffer
static vk::UniqueImage CreateVKImageWrapperForAndroidHarwareBuffer(const vk::Device &device, const AHBProperties &ahb_props, const AHardwareBuffer_Desc &ahb_desc)
Definition: ahb_texture_source_vk.cc:20
impeller::TextureDescriptor::sample_count
SampleCount sample_count
Definition: texture_descriptor.h:45
impeller::ImportVKDeviceMemoryFromAndroidHarwareBuffer
static vk::UniqueDeviceMemory ImportVKDeviceMemoryFromAndroidHarwareBuffer(const vk::Device &device, const vk::PhysicalDevice &physical_device, const vk::Image &image, struct AHardwareBuffer *hardware_buffer, const AHBProperties &ahb_props)
Definition: ahb_texture_source_vk.cc:97
impeller::TextureDescriptor::usage
TextureUsageMask usage
Definition: texture_descriptor.h:44
impeller::PixelFormat::kD32FloatS8UInt
@ kD32FloatS8UInt
impeller::PixelFormat
PixelFormat
The Pixel formats supported by Impeller. The naming convention denotes the usage of the component,...
Definition: formats.h:99
impeller::TextureDescriptor::type
TextureType type
Definition: texture_descriptor.h:40
impeller::TSize
Definition: size.h:19
impeller::android::HardwareBuffer
A wrapper for AHardwareBuffer https://developer.android.com/ndk/reference/group/a-hardware-buffer.
Definition: hardware_buffer.h:95
impeller::StorageMode::kDevicePrivate
@ kDevicePrivate
impeller::CompressionType::kLossless
@ kLossless
impeller::PixelFormat::kD24UnormS8Uint
@ kD24UnormS8Uint
impeller::TextureType::kTextureCube
@ kTextureCube
impeller::PixelFormat::kR16G16B16A16Float
@ kR16G16B16A16Float
impeller::ToTextureType
constexpr GLenum ToTextureType(TextureType type)
Definition: formats_gles.h:169
impeller::AHBTextureSourceVK::GetImage
vk::Image GetImage() const override
Get the image handle for this texture source.
Definition: ahb_texture_source_vk.cc:390
impeller::CreateYUVConversion
static std::shared_ptr< YUVConversionVK > CreateYUVConversion(const ContextVK &context, const AHBProperties &ahb_props)
Definition: ahb_texture_source_vk.cc:141
impeller::TextureType::kTexture2D
@ kTexture2D
impeller::TSize::width
Type width
Definition: size.h:22
impeller::ContextVK
Definition: context_vk.h:42
impeller::TextureDescriptor::size
ISize size
Definition: texture_descriptor.h:42
impeller::ToTextureDescriptor
static TextureDescriptor ToTextureDescriptor(const AHardwareBuffer_Desc &ahb_desc)
Definition: ahb_texture_source_vk.cc:268
VALIDATION_LOG
#define VALIDATION_LOG
Definition: validation.h:73
impeller::AHBTextureSourceVK
A texture source that wraps an instance of AHardwareBuffer.
Definition: ahb_texture_source_vk.h:32
impeller::BackendCast< ContextVK, Context >::Cast
static ContextVK & Cast(Context &base)
Definition: backend_cast.h:13
ahb_texture_source_vk.h
impeller::SampleCount::kCount1
@ kCount1
impeller::ContextVK::GetYUVConversionLibrary
const std::shared_ptr< YUVConversionLibraryVK > & GetYUVConversionLibrary() const
Definition: context_vk.cc:621
impeller::TextureDescriptor::storage_mode
StorageMode storage_mode
Definition: texture_descriptor.h:39
impeller::AHBProperties
vk::StructureChain< vk::AndroidHardwareBufferPropertiesANDROID, vk::AndroidHardwareBufferFormatPropertiesANDROID > AHBProperties
Definition: ahb_texture_source_vk.cc:18
impeller::TextureDescriptor
A lightweight object that describes the attributes of a texture that can then used an allocator to cr...
Definition: texture_descriptor.h:38
context_vk.h
impeller::YUVConversionDescriptorVK
vk::StructureChain< vk::SamplerYcbcrConversionCreateInfo > YUVConversionDescriptorVK
Definition: yuv_conversion_vk.h:30
impeller::AHBTextureSourceVK::GetRenderTargetView
vk::ImageView GetRenderTargetView() const override
Retrieve the image view used for render target attachments with this texture source.
Definition: ahb_texture_source_vk.cc:400
impeller::TextureDescriptor::compression_type
CompressionType compression_type
Definition: texture_descriptor.h:46
impeller
Definition: aiks_blend_unittests.cc:18
impeller::AHBTextureSourceVK::IsSwapchainImage
bool IsSwapchainImage() const override
Determines if swapchain image. That is, an image used as the root render target.
Definition: ahb_texture_source_vk.cc:405
impeller::CreateVKImageView
static vk::UniqueImageView CreateVKImageView(const vk::Device &device, const vk::Image &image, const vk::SamplerYcbcrConversion &yuv_conversion, const AHBProperties &ahb_props, const AHardwareBuffer_Desc &ahb_desc)
Definition: ahb_texture_source_vk.cc:175
impeller::ToPixelFormat
static PixelFormat ToPixelFormat(AHardwareBuffer_Format format)
Definition: ahb_texture_source_vk.cc:221
impeller::AHBTextureSourceVK::GetYUVConversion
std::shared_ptr< YUVConversionVK > GetYUVConversion() const override
When sampling from textures whose formats are not known to Vulkan, a custom conversion is necessary t...
Definition: ahb_texture_source_vk.cc:410