vkGetDescriptorEXT
To get descriptor data to place in a buffer, call:
void vkGetDescriptorEXT(
VkDevice device,
const VkDescriptorGetInfoEXT* pDescriptorInfo,
size_t dataSize,
void* pDescriptor);
deviceis the logical device that gets the descriptor.pDescriptorInfois a pointer to a VkDescriptorGetInfoEXT structure specifying the parameters of the descriptor to get.dataSizeis the amount of the descriptor data to get in bytes.pDescriptoris a pointer to an application-allocated buffer where the descriptor will be written.
The size of the data for each descriptor type is determined by the value in VkPhysicalDeviceDescriptorBufferPropertiesEXT. This value also defines the stride in bytes for arrays of that descriptor type.
If the
VkPhysicalDeviceDescriptorBufferPropertiesEXT::combinedImageSamplerDescriptorSingleArray
property is VK_FALSE the implementation requires an array of
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptors to be written
into a descriptor buffer as an array of image descriptors, immediately
followed by an array of sampler descriptors.
Applications must write the first
VkPhysicalDeviceDescriptorBufferPropertiesEXT::sampledImageDescriptorSize
bytes of the data returned through pDescriptor to the first array, and
the remaining
VkPhysicalDeviceDescriptorBufferPropertiesEXT::samplerDescriptorSize
bytes of the data to the second array.
For variable-sized descriptor bindings of
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptors, the two arrays
each have a size equal to the upper bound descriptorCount of that
binding.
A descriptor obtained by this command references the underlying VkImageView or VkSampler, and these objects must not be destroyed before the last time a descriptor is dynamically accessed. For descriptor types which consume an address instead of an object, the underlying VkBuffer is referenced instead.
Valid Usage
VUID-vkGetDescriptorEXT-None-08015
The descriptorBuffer feature must
be enabled
VUID-vkGetDescriptorEXT-dataSize-08125
If pDescriptorInfo→type is not
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER or
pDescriptorInfo→data.pCombinedImageSampler has an imageView
member that was not created with a VkSamplerYcbcrConversionInfo
structure in its pNext chain,
dataSize must equal the size of a descriptor of type
VkDescriptorGetInfoEXT::type determined by the value in
VkPhysicalDeviceDescriptorBufferPropertiesEXT
, or determined by
VkPhysicalDeviceDescriptorBufferDensityMapPropertiesEXT::combinedImageSamplerDensityMapDescriptorSize
if pDescriptorInfo specifies a
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER whose VkSampler
was created with VK_SAMPLER_CREATE_SUBSAMPLED_BIT_EXT set
VUID-vkGetDescriptorEXT-descriptorType-09469
If pDescriptorInfo→type is
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER and
pDescriptorInfo→data.pCombinedImageSampler has an imageView
member that was created with a VkSamplerYcbcrConversionInfo
structure in its pNext chain, dataSize must equal the size
of
VkPhysicalDeviceDescriptorBufferPropertiesEXT::combinedImageSamplerDescriptorSize
times
VkSamplerYcbcrConversionImageFormatProperties::combinedImageSamplerDescriptorCount
VUID-vkGetDescriptorEXT-pDescriptorInfo-09507
If pDescriptorInfo→type is
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER and it has a
imageView that is VK_NULL_HANDLE then dataSize must
be equal to the size of
VkPhysicalDeviceDescriptorBufferPropertiesEXT::combinedImageSamplerDescriptorSize
Valid Usage (Implicit)
VUID-vkGetDescriptorEXT-device-parameter
device must be a valid VkDevice handle
VUID-vkGetDescriptorEXT-pDescriptorInfo-parameter
pDescriptorInfo must be a valid pointer to a valid VkDescriptorGetInfoEXT structure
VUID-vkGetDescriptorEXT-pDescriptor-parameter
pDescriptor must be a valid pointer to an array of dataSize bytes
VUID-vkGetDescriptorEXT-dataSize-arraylength
dataSize must be greater than 0