Vulkan-Docs/doc/specs/vulkan/chapters/resources.txt

// Copyright (c) 2015-2016 The Khronos Group Inc.
// Copyright notice at https://www.khronos.org/registry/speccopyright.html

[[resources]]
= Resource Creation

Vulkan supports two primary resource types: _buffers_ and _images_.
Resources are views of memory with associated formatting and dimensionality.
Buffers are essentially unformatted arrays of bytes whereas images contain
format information, can: be multidimensional and may: have associated
metadata.


[[resources-buffers]]
== Buffers

// refBegin VkBuffer Opaque handle to a buffer object

Buffers represent linear arrays of data which are used for various purposes
by binding them to a graphics or compute pipeline via descriptor sets or via
certain commands, or by directly specifying them as parameters to certain
commands.

Buffers are represented by sname:VkBuffer handles:

include::../api/handles/VkBuffer.txt[]

// refEnd VkBuffer

// refBegin vkCreateBuffer Create a new buffer object

To create buffers, call:

include::../api/protos/vkCreateBuffer.txt[]

  * pname:device is the logical device that creates the buffer object.
  * pname:pCreateInfo is a pointer to an instance of the
    sname:VkBufferCreateInfo structure containing parameters affecting
    creation of the buffer.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.
  * pname:pBuffer points to a sname:VkBuffer handle in which the resulting
    buffer object is returned.

.Valid Usage
****
  * If the pname:flags member of pname:pCreateInfo includes
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT, creating this sname:VkBuffer
    must: not cause the total required sparse memory for all currently valid
    sparse resources on the device to exceed
    sname:VkPhysicalDeviceLimits::pname:sparseAddressSpaceSize
****

include::../validity/protos/vkCreateBuffer.txt[]

// refBegin VkBufferCreateInfo Structure specifying the parameters of a newly created buffer object

The sname:VkBufferCreateInfo structure is defined as:

include::../api/structs/VkBufferCreateInfo.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:flags is a bitmask describing additional parameters of the buffer.
    See elink:VkBufferCreateFlagBits below for a description of the
    supported bits.
  * pname:size is the size in bytes of the buffer to be created.
  * pname:usage is a bitmask describing the allowed usages of the buffer.
    See elink:VkBufferUsageFlagBits below for a description of the supported
    bits.
  * pname:sharingMode is the sharing mode of the buffer when it will be
    accessed by multiple queue families, see elink:VkSharingMode in the
    <<resources-sharing,Resource Sharing>> section below for supported
    values.
  * pname:queueFamilyIndexCount is the number of entries in the
    pname:pQueueFamilyIndices array.
  * pname:pQueueFamilyIndices is a list of queue families that will access
    this buffer (ignored if pname:sharingMode is not
    ename:VK_SHARING_MODE_CONCURRENT).

Bits which can: be set in pname:usage are:

// refBegin VkBufferUsageFlagBits Bitmask specifying allowed usage of a buffer
include::../api/enums/VkBufferUsageFlagBits.txt[]

  * ename:VK_BUFFER_USAGE_TRANSFER_SRC_BIT indicates that the buffer can: be
    used as the source of a _transfer command_ (see the definition of
    <<synchronization-transfer,ename:VK_PIPELINE_STAGE_TRANSFER_BIT>>).
  * ename:VK_BUFFER_USAGE_TRANSFER_DST_BIT indicates that the buffer can: be
    used as the destination of a transfer command.
  * ename:VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT indicates that the buffer
    can: be used to create a sname:VkBufferView suitable for occupying a
    sname:VkDescriptorSet slot of type
    ename:VK_DESCRIPTOR_TYPE_UNIFORM_TEXEL_BUFFER.
  * ename:VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT indicates that the buffer
    can: be used to create a sname:VkBufferView suitable for occupying a
    sname:VkDescriptorSet slot of type
    ename:VK_DESCRIPTOR_TYPE_STORAGE_TEXEL_BUFFER.
  * ename:VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT indicates that the buffer can:
    be used in a sname:VkDescriptorBufferInfo suitable for occupying a
    sname:VkDescriptorSet slot either of type
    ename:VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER or
    ename:VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC.
  * ename:VK_BUFFER_USAGE_STORAGE_BUFFER_BIT indicates that the buffer can:
    be used in a sname:VkDescriptorBufferInfo suitable for occupying a
    sname:VkDescriptorSet slot either of type
    ename:VK_DESCRIPTOR_TYPE_STORAGE_BUFFER or
    ename:VK_DESCRIPTOR_TYPE_STORAGE_BUFFER_DYNAMIC.
  * ename:VK_BUFFER_USAGE_INDEX_BUFFER_BIT indicates that the buffer is
    suitable for passing as the pname:buffer parameter to
    fname:vkCmdBindIndexBuffer.
  * ename:VK_BUFFER_USAGE_VERTEX_BUFFER_BIT indicates that the buffer is
    suitable for passing as an element of the pname:pBuffers array to
    fname:vkCmdBindVertexBuffers.
  * ename:VK_BUFFER_USAGE_INDIRECT_BUFFER_BIT indicates that the buffer is
    suitable for passing as the pname:buffer parameter to
    fname:vkCmdDrawIndirect, fname:vkCmdDrawIndexedIndirect, or
    fname:vkCmdDispatchIndirect.

Any combination of bits can: be specified for pname:usage, but at least one
of the bits must: be set in order to create a valid buffer.

Bits which can: be set in pname:flags are:

// refBegin VkBufferCreateFlagBits Bitmask specifying additional parameters of a buffer
include::../api/enums/VkBufferCreateFlagBits.txt[]

These bits have the following meanings:

  * ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT indicates that the buffer will
    be backed using sparse memory binding.
  * ename:VK_BUFFER_CREATE_SPARSE_RESIDENCY_BIT indicates that the buffer
    can: be partially backed using sparse memory binding.
    Buffers created with this flag must: also be created with the
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT flag.
  * ename:VK_BUFFER_CREATE_SPARSE_ALIASED_BIT indicates that the buffer will
    be backed using sparse memory binding with memory ranges that might also
    simultaneously be backing another buffer (or another portion of the same
    buffer).
    Buffers created with this flag must: also be created with the
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT flag.

See <<sparsememory-sparseresourcefeatures,Sparse Resource Features>> and
<<features-features,Physical Device Features>> for details of the sparse
memory features supported on a device.

.Valid Usage
****
  * pname:size must: be greater than `0`
  * If pname:sharingMode is ename:VK_SHARING_MODE_CONCURRENT,
    pname:pQueueFamilyIndices must: be a pointer to an array of
    pname:queueFamilyIndexCount basetype:uint32_t values
  * If pname:sharingMode is ename:VK_SHARING_MODE_CONCURRENT,
    pname:queueFamilyIndexCount must: be greater than `1`
  * If the <<features-features-sparseBinding,sparse bindings>> feature is
    not enabled, pname:flags must: not contain
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT
  * If the <<features-features-sparseResidencyBuffer,sparse buffer
    residency>> feature is not enabled, pname:flags must: not contain
    ename:VK_BUFFER_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidencyAliased,sparse aliased
    residency>> feature is not enabled, pname:flags must: not contain
    ename:VK_BUFFER_CREATE_SPARSE_ALIASED_BIT
  * If pname:flags contains ename:VK_BUFFER_CREATE_SPARSE_RESIDENCY_BIT or
    ename:VK_BUFFER_CREATE_SPARSE_ALIASED_BIT, it must: also contain
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT
****

include::../validity/structs/VkBufferCreateInfo.txt[]

ifdef::VK_NV_dedicated_allocation[]

// refBegin VkDedicatedAllocationBufferCreateInfoNV Specify that a buffer is bound to a dedicated memory resource

If the pname:pNext list includes a
sname:VkDedicatedAllocationBufferCreateInfoNV structure, then that structure
includes an enable controlling whether the buffer will have a dedicated
memory allocation bound to it.

The sname:VkDedicatedAllocationBufferCreateInfoNV structure is defined as:

include::../api/structs/VkDedicatedAllocationBufferCreateInfoNV.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:dedicatedAllocation indicates whether the buffer will have a
    dedicated allocation bound to it.

.Valid Usage
****
  * If pname:dedicatedAllocation is ename:VK_TRUE,
    sname:VkBufferCreateInfo::pname:flags must: not include
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT,
    ename:VK_BUFFER_CREATE_SPARSE_RESIDENCY_BIT, or
    ename:VK_BUFFER_CREATE_SPARSE_ALIASED_BIT
****

include::../validity/structs/VkDedicatedAllocationBufferCreateInfoNV.txt[]

endif::VK_NV_dedicated_allocation[]

// refBegin vkDestroyBuffer Destroy a buffer object

To destroy a buffer, call:

include::../api/protos/vkDestroyBuffer.txt[]

  * pname:device is the logical device that destroys the buffer.
  * pname:buffer is the buffer to destroy.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.

.Valid Usage
****
  * All submitted commands that refer to pname:buffer, either directly or
    via a sname:VkBufferView, must: have completed execution
  * If sname:VkAllocationCallbacks were provided when pname:buffer was
    created, a compatible set of callbacks must: be provided here
  * If no sname:VkAllocationCallbacks were provided when pname:buffer was
    created, pname:pAllocator must: be `NULL`
****

include::../validity/protos/vkDestroyBuffer.txt[]


[[resources-buffer-views]]
== Buffer Views

// refBegin VkBufferView Opaque handle to a buffer view object

A _buffer view_ represents a contiguous range of a buffer and a specific
format to be used to interpret the data.
Buffer views are used to enable shaders to access buffer contents
interpreted as formatted data.
In order to create a valid buffer view, the buffer must: have been created
with at least one of the following usage flags:

  * ename:VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT
  * ename:VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT

Buffer views are represented by sname:VkBufferView handles:

include::../api/handles/VkBufferView.txt[]

// refEnd VkBufferView

// refBegin vkCreateBufferView Create a new buffer view object

To create a buffer view, call:

include::../api/protos/vkCreateBufferView.txt[]

  * pname:device is the logical device that creates the buffer view.
  * pname:pCreateInfo is a pointer to an instance of the
    sname:VkBufferViewCreateInfo structure containing parameters to be used
    to create the buffer.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.
  * pname:pView points to a sname:VkBufferView handle in which the resulting
    buffer view object is returned.

include::../validity/protos/vkCreateBufferView.txt[]

// refBegin VkBufferViewCreateInfo Structure specifying parameters of a newly created buffer view

The sname:VkBufferViewCreateInfo structure is defined as:

include::../api/structs/VkBufferViewCreateInfo.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:flags is reserved for future use.
  * pname:buffer is a sname:VkBuffer on which the view will be created.
  * pname:format is a elink:VkFormat describing the format of the data
    elements in the buffer.
  * pname:offset is an offset in bytes from the base address of the buffer.
    Accesses to the buffer view from shaders use addressing that is relative
    to this starting offset.
  * pname:range is a size in bytes of the buffer view.
    If pname:range is equal to ename:VK_WHOLE_SIZE, the range from
    pname:offset to the end of the buffer is used.
    If ename:VK_WHOLE_SIZE is used and the remaining size of the buffer is
    not a multiple of the element size of pname:format, then the nearest
    smaller multiple is used.

.Valid Usage
****
  * pname:offset must: be less than the size of pname:buffer
  * pname:offset must: be a multiple of
    sname:VkPhysicalDeviceLimits::pname:minTexelBufferOffsetAlignment
  * If pname:range is not equal to ename:VK_WHOLE_SIZE:
  ** pname:range must: be greater than `0`
  ** pname:range must: be a multiple of the element size of pname:format
  ** pname:range divided by the element size of pname:format, must: be
     less than or equal to
     sname:VkPhysicalDeviceLimits::pname:maxTexelBufferElements
  ** the sum of pname:offset and pname:range must: be less than or equal to
     the size of pname:buffer
  * pname:buffer must: have been created with a pname:usage value containing
    at least one of ename:VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT or
    ename:VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT
  * If pname:buffer was created with pname:usage containing
    ename:VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT, pname:format must: be
    supported for uniform texel buffers, as specified by the
    ename:VK_FORMAT_FEATURE_UNIFORM_TEXEL_BUFFER_BIT flag in
    sname:VkFormatProperties::pname:bufferFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties
  * If pname:buffer was created with pname:usage containing
    ename:VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT, pname:format must: be
    supported for storage texel buffers, as specified by the
    ename:VK_FORMAT_FEATURE_STORAGE_TEXEL_BUFFER_BIT flag in
    sname:VkFormatProperties::pname:bufferFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties
****

include::../validity/structs/VkBufferViewCreateInfo.txt[]

// refBegin vkDestroyBufferView Destroy a buffer view object

To destroy a buffer view, call:

include::../api/protos/vkDestroyBufferView.txt[]

  * pname:device is the logical device that destroys the buffer view.
  * pname:bufferView is the buffer view to destroy.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.

.Valid Usage
****
  * All submitted commands that refer to pname:bufferView must: have
    completed execution
  * If sname:VkAllocationCallbacks were provided when pname:bufferView was
    created, a compatible set of callbacks must: be provided here
  * If no sname:VkAllocationCallbacks were provided when pname:bufferView
    was created, pname:pAllocator must: be `NULL`
****

include::../validity/protos/vkDestroyBufferView.txt[]


[[resources-images]]
== Images

// refBegin VkImage Opaque handle to a image object

Images represent multidimensional - up to 3 - arrays of data which can: be
used for various purposes (e.g. attachments, textures), by binding them to a
graphics or compute pipeline via descriptor sets, or by directly specifying
them as parameters to certain commands.

Images are represented by sname:VkImage handles:

include::../api/handles/VkImage.txt[]

// refEnd VkImage

// refBegin vkCreateImage Create a new image object

To create images, call:

include::../api/protos/vkCreateImage.txt[]

  * pname:device is the logical device that creates the image.
  * pname:pCreateInfo is a pointer to an instance of the
    sname:VkImageCreateInfo structure containing parameters to be used to
    create the image.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.
  * pname:pImage points to a sname:VkImage handle in which the resulting
    image object is returned.

.Valid Usage
****
  * If the pname:flags member of pname:pCreateInfo includes
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT, creating this sname:VkImage
    must: not cause the total required sparse memory for all currently valid
    sparse resources on the device to exceed
    sname:VkPhysicalDeviceLimits::pname:sparseAddressSpaceSize
****

include::../validity/protos/vkCreateImage.txt[]

// refBegin VkImageCreateInfo Structure specifying the parameters of a newly created image object

The sname:VkImageCreateInfo structure is defined as:

include::../api/structs/VkImageCreateInfo.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:flags is a bitmask describing additional parameters of the image.
    See elink:VkImageCreateFlagBits below for a description of the supported
    bits.
  * pname:imageType is a elink:VkImageType specifying the basic
    dimensionality of the image, as described below.
    Layers in array textures do not count as a dimension for the purposes of
    the image type.
  * pname:format is a elink:VkFormat describing the format and type of the
    data elements that will be contained in the image.
  * pname:extent is a slink:VkExtent3D describing the number of data
    elements in each dimension of the base level.
  * pname:mipLevels describes the number of levels of detail available for
    minified sampling of the image.
  * pname:arrayLayers is the number of layers in the image.
  * pname:samples is the number of sub-data element samples in the image as
    defined in elink:VkSampleCountFlagBits.
    See <<primsrast-multisampling,Multisampling>>.
  * pname:tiling is a elink:VkImageTiling specifying the tiling arrangement
    of the data elements in memory, as described below.
  * pname:usage is a bitmask describing the intended usage of the image.
    See elink:VkImageUsageFlagBits below for a description of the supported
    bits.
  * pname:sharingMode is the sharing mode of the image when it will be
    accessed by multiple queue families, and must: be one of the values
    described for elink:VkSharingMode in the <<resources-sharing,Resource
    Sharing>> section below.
  * pname:queueFamilyIndexCount is the number of entries in the
    pname:pQueueFamilyIndices array.
  * pname:pQueueFamilyIndices is a list of queue families that will access
    this image (ignored if pname:sharingMode is not
    ename:VK_SHARING_MODE_CONCURRENT).
  * pname:initialLayout selects the initial elink:VkImageLayout state of all
    image subresources of the image.
    See <<resources-image-layouts,Image Layouts>>.
    pname:initialLayout must: be ename:VK_IMAGE_LAYOUT_UNDEFINED or
    ename:VK_IMAGE_LAYOUT_PREINITIALIZED.

Valid limits for the image pname:extent, pname:mipLevels, pname:arrayLayers
and pname:samples members are queried with the
flink:vkGetPhysicalDeviceImageFormatProperties command.

Images created with pname:tiling equal to ename:VK_IMAGE_TILING_LINEAR have
further restrictions on their limits and capabilities compared to images
created with pname:tiling equal to ename:VK_IMAGE_TILING_OPTIMAL.
Creation of images with tiling ename:VK_IMAGE_TILING_LINEAR may: not be
supported unless other parameters meet all of the constraints:

  * pname:imageType is ename:VK_IMAGE_TYPE_2D
  * pname:format is not a depth/stencil format
  * pname:mipLevels is 1
  * pname:arrayLayers is 1
  * pname:samples is ename:VK_SAMPLE_COUNT_1_BIT
  * pname:usage only includes ename:VK_IMAGE_USAGE_TRANSFER_SRC_BIT and/or
    ename:VK_IMAGE_USAGE_TRANSFER_DST_BIT

Implementations may: support additional limits and capabilities beyond those
listed above.
To determine the specific capabilities of an implementation, query the valid
pname:usage bits by calling flink:vkGetPhysicalDeviceFormatProperties and
the valid limits for pname:mipLevels and pname:arrayLayers by calling
flink:vkGetPhysicalDeviceImageFormatProperties.

.Valid Usage
****
  * If pname:sharingMode is ename:VK_SHARING_MODE_CONCURRENT,
    pname:pQueueFamilyIndices must: be a pointer to an array of
    pname:queueFamilyIndexCount basetype:uint32_t values
  * If pname:sharingMode is ename:VK_SHARING_MODE_CONCURRENT,
    pname:queueFamilyIndexCount must: be greater than `1`
  * pname:format must: not be ename:VK_FORMAT_UNDEFINED
  * The pname:width, pname:height, and pname:depth members of pname:extent
    must: all be greater than `0`
  * pname:mipLevels must: be greater than `0`
  * pname:arrayLayers must: be greater than `0`
  * If pname:flags contains ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT,
    pname:imageType must be ename:VK_IMAGE_TYPE_2D
  * If pname:imageType is ename:VK_IMAGE_TYPE_1D, pname:extent.width must:
    be less than or equal to
    sname:VkPhysicalDeviceLimits::pname:maxImageDimension1D, or
    sname:VkImageFormatProperties::pname:maxExtent.width (as returned by
    fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure) - whichever is higher
  * If pname:imageType is ename:VK_IMAGE_TYPE_2D and pname:flags does not
    contain ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT, pname:extent.width
    and pname:extent.height must: be less than or equal to
    sname:VkPhysicalDeviceLimits::pname:maxImageDimension2D, or
    sname:VkImageFormatProperties::pname:maxExtent.width/height (as returned
    by fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure) - whichever is higher
  * If pname:imageType is ename:VK_IMAGE_TYPE_2D and pname:flags contains
    ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT, pname:extent.width and
    pname:extent.height must: be less than or equal to
    sname:VkPhysicalDeviceLimits::pname:maxImageDimensionCube, or
    sname:VkImageFormatProperties::pname:maxExtent.width/height (as returned
    by fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure) - whichever is higher
  * If pname:imageType is ename:VK_IMAGE_TYPE_2D and pname:flags contains
    ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT, pname:extent.width and
    pname:extent.height must: be equal and pname:arrayLayers must: be
    greater than or equal to 6
  * If pname:imageType is ename:VK_IMAGE_TYPE_3D, pname:extent.width,
    pname:extent.height and pname:extent.depth must: be less than or equal
    to sname:VkPhysicalDeviceLimits::pname:maxImageDimension3D, or
    sname:VkImageFormatProperties::pname:maxExtent.width/height/depth (as
    returned by fname:vkGetPhysicalDeviceImageFormatProperties with
    pname:format, pname:type, pname:tiling, pname:usage, and pname:flags
    equal to those in this structure) - whichever is higher
  * If pname:imageType is ename:VK_IMAGE_TYPE_1D, both pname:extent.height
    and pname:extent.depth must: be `1`
  * If pname:imageType is ename:VK_IMAGE_TYPE_2D, pname:extent.depth must:
    be `1`
  * pname:mipLevels must: be less than or equal to
    [eq]#{lfloor}log~2~(max(pname:extent.width, pname:extent.height,
    pname:extent.depth)){rfloor} + 1#.
  * If any of pname:extent.width, pname:extent.height, or pname:extent.depth
    are greater than the equivalently named members of
    sname:VkPhysicalDeviceLimits::pname:maxImageDimension3D, pname:mipLevels
    must: be less than or equal to
    sname:VkImageFormatProperties::pname:maxMipLevels (as returned by
    fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure)
  * pname:arrayLayers must: be less than or equal to
    sname:VkImageFormatProperties::pname:maxArrayLayers (as returned by
    fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure)
  * If pname:samples is not ename:VK_SAMPLE_COUNT_1_BIT, pname:imageType
    must: be ename:VK_IMAGE_TYPE_2D, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT, pname:tiling must: be
    ename:VK_IMAGE_TILING_OPTIMAL, and pname:mipLevels must: be equal to `1`
  * If pname:usage includes ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT,
    then bits other than ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
    ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, and
    ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT must: not be set
  * If pname:usage includes ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
    ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
    ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT, or
    ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, pname:extent.width must: be
    less than or equal to
    sname:VkPhysicalDeviceLimits::pname:maxFramebufferWidth
  * If pname:usage includes ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
    ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
    ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT, or
    ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, pname:extent.height must: be
    less than or equal to
    sname:VkPhysicalDeviceLimits::pname:maxFramebufferHeight
  * pname:samples must: be a bit value that is set in
    sname:VkImageFormatProperties::pname:sampleCounts returned by
    fname:vkGetPhysicalDeviceImageFormatProperties with pname:format,
    pname:type, pname:tiling, pname:usage, and pname:flags equal to those in
    this structure
  * If the <<features-features-textureCompressionETC2,ETC2 texture
    compression>> feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_ETC2_R8G8B8_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8_SRGB_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A1_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A1_SRGB_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A8_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A8_SRGB_BLOCK,
    ename:VK_FORMAT_EAC_R11_UNORM_BLOCK,
    ename:VK_FORMAT_EAC_R11_SNORM_BLOCK,
    ename:VK_FORMAT_EAC_R11G11_UNORM_BLOCK, or
    ename:VK_FORMAT_EAC_R11G11_SNORM_BLOCK
  * If the <<features-features-textureCompressionASTC_LDR,ASTC LDR texture
    compression>> feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_ASTC_4x4_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_4x4_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_5x4_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_5x4_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_5x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_5x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_6x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_6x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_6x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_6x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x8_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x8_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x8_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x8_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x10_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x10_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_12x10_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_12x10_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_12x12_UNORM_BLOCK, or
    ename:VK_FORMAT_ASTC_12x12_SRGB_BLOCK
  * If the <<features-features-textureCompressionBC,BC texture compression>>
    feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_BC1_RGB_UNORM_BLOCK, ename:VK_FORMAT_BC1_RGB_SRGB_BLOCK,
    ename:VK_FORMAT_BC1_RGBA_UNORM_BLOCK,
    ename:VK_FORMAT_BC1_RGBA_SRGB_BLOCK, ename:VK_FORMAT_BC2_UNORM_BLOCK,
    ename:VK_FORMAT_BC2_SRGB_BLOCK, ename:VK_FORMAT_BC3_UNORM_BLOCK,
    ename:VK_FORMAT_BC3_SRGB_BLOCK, ename:VK_FORMAT_BC4_UNORM_BLOCK,
    ename:VK_FORMAT_BC4_SNORM_BLOCK, ename:VK_FORMAT_BC5_UNORM_BLOCK,
    ename:VK_FORMAT_BC5_SNORM_BLOCK, ename:VK_FORMAT_BC6H_UFLOAT_BLOCK,
    ename:VK_FORMAT_BC6H_SFLOAT_BLOCK, ename:VK_FORMAT_BC7_UNORM_BLOCK, or
    ename:VK_FORMAT_BC7_SRGB_BLOCK
  * If the <<features-features-shaderStorageImageMultisample,multisampled
    storage images>> feature is not enabled, and pname:usage contains
    ename:VK_IMAGE_USAGE_STORAGE_BIT, pname:samples must: be
    ename:VK_SAMPLE_COUNT_1_BIT
  * If the <<features-features-sparseBinding,sparse bindings>> feature is
    not enabled, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT
  * If the <<features-features-sparseResidencyImage2D,sparse residency for
    2D images>> feature is not enabled, and pname:imageType is
    ename:VK_IMAGE_TYPE_2D, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidencyImage3D,sparse residency for
    3D images>> feature is not enabled, and pname:imageType is
    ename:VK_IMAGE_TYPE_3D, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidency2Samples,sparse residency for
    images with 2 samples>> feature is not enabled, pname:imageType is
    ename:VK_IMAGE_TYPE_2D, and pname:samples is
    ename:VK_SAMPLE_COUNT_2_BIT, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidency4Samples,sparse residency for
    images with 4 samples>> feature is not enabled, pname:imageType is
    ename:VK_IMAGE_TYPE_2D, and pname:samples is
    ename:VK_SAMPLE_COUNT_4_BIT, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidency8Samples,sparse residency for
    images with 8 samples>> feature is not enabled, pname:imageType is
    ename:VK_IMAGE_TYPE_2D, and pname:samples is
    ename:VK_SAMPLE_COUNT_8_BIT, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If the <<features-features-sparseResidency16Samples,sparse residency for
    images with 16 samples>> feature is not enabled, pname:imageType is
    ename:VK_IMAGE_TYPE_2D, and pname:samples is
    ename:VK_SAMPLE_COUNT_16_BIT, pname:flags must: not contain
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_LINEAR, pname:format must: be a
    format that has at least one supported feature bit present in the value
    of sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:tiling is ename:VK_IMAGE_TILING_LINEAR, and
    sname:VkFormatProperties::pname:linearTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_BIT, pname:usage must: not contain
    ename:VK_IMAGE_USAGE_SAMPLED_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_LINEAR, and
    sname:VkFormatProperties::pname:linearTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT, pname:usage must: not contain
    ename:VK_IMAGE_USAGE_STORAGE_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_LINEAR, and
    sname:VkFormatProperties::pname:linearTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_COLOR_ATTACHMENT_BIT, pname:usage must: not
    contain ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_LINEAR, and
    sname:VkFormatProperties::pname:linearTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_DEPTH_STENCIL_ATTACHMENT_BIT, pname:usage must:
    not contain ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_OPTIMAL, pname:format must: be
    a format that has at least one supported feature bit present in the
    value of sname:VkFormatProperties::pname:optimalTilingFeatures returned
    by fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:tiling is ename:VK_IMAGE_TILING_OPTIMAL, and
    sname:VkFormatProperties::pname:optimalTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_BIT, pname:usage must: not contain
    ename:VK_IMAGE_USAGE_SAMPLED_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_OPTIMAL, and
    sname:VkFormatProperties::pname:optimalTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT, pname:usage must: not contain
    ename:VK_IMAGE_USAGE_STORAGE_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_OPTIMAL, and
    sname:VkFormatProperties::pname:optimalTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_COLOR_ATTACHMENT_BIT, pname:usage must: not
    contain ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT
  * If pname:tiling is ename:VK_IMAGE_TILING_OPTIMAL, and
    sname:VkFormatProperties::pname:optimalTilingFeatures (as returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format) does not include
    ename:VK_FORMAT_FEATURE_DEPTH_STENCIL_ATTACHMENT_BIT, pname:usage must:
    not contain ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT
  * If pname:flags contains ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT or
    ename:VK_IMAGE_CREATE_SPARSE_ALIASED_BIT, it must: also contain
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT
****

include::../validity/structs/VkImageCreateInfo.txt[]

ifdef::VK_NV_dedicated_allocation[]

// refBegin VkDedicatedAllocationImageCreateInfoNV Specify that an image is bound to a dedicated memory resource

If the pname:pNext list includes a
sname:VkDedicatedAllocationImageCreateInfoNV structure, then that structure
includes an enable controlling whether the image will have a dedicated
memory allocation bound to it.

The sname:VkDedicatedAllocationImageCreateInfoNV structure is defined as:

include::../api/structs/VkDedicatedAllocationImageCreateInfoNV.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:dedicatedAllocation indicates whether the image will have a
    dedicated allocation bound to it.

[NOTE]
.Note
====
Using a dedicated allocation for color and depth/stencil attachments or
other large images may: improve performance on some devices.
====

.Valid Usage
****
  * If pname:dedicatedAllocation is ename:VK_TRUE,
    sname:VkImageCreateInfo::pname:flags must: not include
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT,
    ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT, or
    ename:VK_IMAGE_CREATE_SPARSE_ALIASED_BIT
****

include::../validity/structs/VkDedicatedAllocationImageCreateInfoNV.txt[]

endif::VK_NV_dedicated_allocation[]

ifdef::VK_NV_external_memory[]

// refBegin VkExternalMemoryImageCreateInfoNV Specify that an image may be backed by external memory

If the pname:pNext list includes a sname:VkExternalMemoryImageCreateInfoNV
structure, then that structure defines a set of external memory handle types
that may: be used as backing store for the image.

The sname:VkExternalMemoryImageCreateInfoNV structure is defined as:

include::../api/structs/VkExternalMemoryImageCreateInfoNV.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:handleTypes is a bitmask of
    elink:VkExternalMemoryHandleTypeFlagBitsNV specifying one or more
    external memory handle types.
    The types must: all be compatible with each other and the other image
    creation parameters, as reported by
    flink:vkGetPhysicalDeviceExternalImageFormatPropertiesNV.

include::../validity/structs/VkExternalMemoryImageCreateInfoNV.txt[]

endif::VK_NV_external_memory[]

// refBegin VkImageUsageFlagBits Bitmask specifying intended usage of an image

The intended usage of an image is specified by the bitmask
slink:VkImageCreateInfo::pname:usage.
Bits which can: be set include:

include::../api/enums/VkImageUsageFlagBits.txt[]

These bits have the following meanings:

  * ename:VK_IMAGE_USAGE_TRANSFER_SRC_BIT indicates that the image can: be
    used as the source of a transfer command.
  * ename:VK_IMAGE_USAGE_TRANSFER_DST_BIT indicates that the image can: be
    used as the destination of a transfer command.
  * ename:VK_IMAGE_USAGE_SAMPLED_BIT indicates that the image can: be used
    to create a sname:VkImageView suitable for occupying a
    sname:VkDescriptorSet slot either of type
    ename:VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE or
    ename:VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, and be sampled by a
    shader.
  * ename:VK_IMAGE_USAGE_STORAGE_BIT indicates that the image can: be used
    to create a sname:VkImageView suitable for occupying a
    sname:VkDescriptorSet slot of type
    ename:VK_DESCRIPTOR_TYPE_STORAGE_IMAGE.
  * ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT indicates that the image can:
    be used to create a sname:VkImageView suitable for use as a color or
    resolve attachment in a sname:VkFramebuffer.
  * ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT indicates that the
    image can: be used to create a sname:VkImageView suitable for use as a
    depth/stencil attachment in a sname:VkFramebuffer.
  * ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT indicates that the memory
    bound to this image will have been allocated with the
    ename:VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT (see <<memory>> for more
    detail).
    This bit can: be set for any image that can: be used to create a
    sname:VkImageView suitable for use as a color, resolve, depth/stencil,
    or input attachment.
  * ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT indicates that the image can:
    be used to create a sname:VkImageView suitable for occupying
    sname:VkDescriptorSet slot of type
    ename:VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT; be read from a shader as an
    input attachment; and be used as an input attachment in a framebuffer.

// refEnd VkImageUsageFlagBits

// refBegin VkImageCreateFlagBits Bitmask specifying additional parameters of an image

Additional parameters of an image are specified by
slink:VkImageCreateInfo::pname:flags.
Bits which can: be set include:

include::../api/enums/VkImageCreateFlagBits.txt[]

These bits have the following meanings:

  * ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT indicates that the image will
    be backed using sparse memory binding.
  * ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT indicates that the image can:
    be partially backed using sparse memory binding.
    Images created with this flag must: also be created with the
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT flag.
  * ename:VK_IMAGE_CREATE_SPARSE_ALIASED_BIT indicates that the image will
    be backed using sparse memory binding with memory ranges that might also
    simultaneously be backing another image (or another portion of the same
    image).
    Images created with this flag must: also be created with the
    ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT flag
  * ename:VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT indicates that the image can:
    be used to create a sname:VkImageView with a different format from the
    image.
  * ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT indicates that the image can:
    be used to create a sname:VkImageView of type
    ename:VK_IMAGE_VIEW_TYPE_CUBE or ename:VK_IMAGE_VIEW_TYPE_CUBE_ARRAY.

If any of the bits ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT,
ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT, or
ename:VK_IMAGE_CREATE_SPARSE_ALIASED_BIT are set,
ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT must: not also be set.

See <<sparsememory-sparseresourcefeatures,Sparse Resource Features>> and
<<sparsememory-physicalfeatures,Sparse Physical Device Features>> for more
details.

// refEnd VkImageCreateFlagBits

// refBegin VkImageType Specifies the type of an image object

The basic dimensionality of an image is specified by
slink:VkImageCreateInfo::pname:imageType, which must: be one of the values

include::../api/enums/VkImageType.txt[]

These values specify one-, two-, or three-dimensional images, respectively.

// refEnd VkImageType

// refBegin VkImageTiling Specifies the tiling arrangement of data in an image

The tiling arrangement of data elements in an image is specified by
slink:VkImageCreateInfo::pname:tiling, which must: be one of the values

include::../api/enums/VkImageTiling.txt[]

ename:VK_IMAGE_TILING_OPTIMAL specifies optimal tiling (texels are laid out
in an implementation-dependent arrangement, for more optimal memory access),
and ename:VK_IMAGE_TILING_LINEAR specifies linear tiling (texels are laid
out in memory in row-major order, possibly with some padding on each row).

// refEnd VkImageTiling

// refBegin vkGetImageSubresourceLayout Retrieve information about an image subresource

To query the host access layout of an image subresource, for an image
created with linear tiling, call:

include::../api/protos/vkGetImageSubresourceLayout.txt[]

  * pname:device is the logical device that owns the image.
  * pname:image is the image whose layout is being queried.
  * pname:pSubresource is a pointer to a slink:VkImageSubresource structure
    selecting a specific image for the image subresource.
  * pname:pLayout points to a slink:VkSubresourceLayout structure in which
    the layout is returned.

flink:vkGetImageSubresourceLayout is invariant for the lifetime of a single
image.

.Valid Usage
****
  * pname:image must: have been created with pname:tiling equal to
    ename:VK_IMAGE_TILING_LINEAR
  * The pname:aspectMask member of pname:pSubresource must: only have a
    single bit set
****

include::../validity/protos/vkGetImageSubresourceLayout.txt[]

// refBegin VkImageSubresource Structure specifying a image subresource

The sname:VkImageSubresource structure is defined as:

include::../api/structs/VkImageSubresource.txt[]

  * pname:aspectMask is a elink:VkImageAspectFlags selecting the image
    _aspect_.
  * pname:mipLevel selects the mipmap level.
  * pname:arrayLayer selects the array layer.

.Valid Usage
****
  * pname:mipLevel must: be less than the pname:mipLevels specified in
    slink:VkImageCreateInfo when the image was created
  * pname:arrayLayer must: be less than the pname:arrayLayers specified in
    slink:VkImageCreateInfo when the image was created
****

include::../validity/structs/VkImageSubresource.txt[]

// refBegin VkSubresourceLayout Structure specifying subresource layout

Information about the layout of the image subresource is returned in a
sname:VkSubresourceLayout structure:

include::../api/structs/VkSubresourceLayout.txt[]

  * pname:offset is the byte offset from the start of the image where the
    image subresource begins.
  * pname:size is the size in bytes of the image subresource.
    pname:size includes any extra memory that is required based on
    pname:rowPitch.
  * pname:rowPitch describes the number of bytes between each row of texels
    in an image.
  * pname:arrayPitch describes the number of bytes between each array layer
    of an image.
  * pname:depthPitch describes the number of bytes between each slice of 3D
    image.

For images created with linear tiling, pname:rowPitch, pname:arrayPitch and
pname:depthPitch describe the layout of the image subresource in linear
memory.
For uncompressed formats, pname:rowPitch is the number of bytes between
texels with the same x coordinate in adjacent rows (y coordinates differ by
one).
pname:arrayPitch is the number of bytes between texels with the same x and y
coordinate in adjacent array layers of the image (array layer values differ
by one).
pname:depthPitch is the number of bytes between texels with the same x and y
coordinate in adjacent slices of a 3D image (z coordinates differ by one).
Expressed as an addressing formula, the starting byte of a texel in the
image subresource has address:

[source,c]
---------------------------------------------------
// (x,y,z,layer) are in texel coordinates
address(x,y,z,layer) = layer*arrayPitch + z*depthPitch + y*rowPitch + x*elementSize + offset
---------------------------------------------------

For compressed formats, the pname:rowPitch is the number of bytes between
compressed texel blocks in adjacent rows.
pname:arrayPitch is the number of bytes between compressed texel blocks in
adjacent array layers.
pname:depthPitch is the number of bytes between compressed texel blocks in
adjacent slices of a 3D image.

[source,c]
---------------------------------------------------
// (x,y,z,layer) are in compressed texel block coordinates
address(x,y,z,layer) = layer*arrayPitch + z*depthPitch + y*rowPitch + x*compressedTexelBlockByteSize + offset;
---------------------------------------------------

pname:arrayPitch is undefined for images that were not created as arrays.
pname:depthPitch is defined only for 3D images.

For color formats, the pname:aspectMask member of sname:VkImageSubresource
must: be ename:VK_IMAGE_ASPECT_COLOR_BIT.
For depth/stencil formats, pname:aspectMask must: be either
ename:VK_IMAGE_ASPECT_DEPTH_BIT or ename:VK_IMAGE_ASPECT_STENCIL_BIT.
On implementations that store depth and stencil aspects separately, querying
each of these image subresource layouts will return a different pname:offset
and pname:size representing the region of memory used for that aspect.
On implementations that store depth and stencil aspects interleaved, the
same pname:offset and pname:size are returned and represent the interleaved
memory allocation.

include::../validity/structs/VkSubresourceLayout.txt[]

// refBegin vkDestroyImage Destroy an image object

To destroy an image, call:

include::../api/protos/vkDestroyImage.txt[]

  * pname:device is the logical device that destroys the image.
  * pname:image is the image to destroy.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.

.Valid Usage
****
  * All submitted commands that refer to pname:image, either directly or via
    a sname:VkImageView, must: have completed execution
  * If sname:VkAllocationCallbacks were provided when pname:image was
    created, a compatible set of callbacks must: be provided here
  * If no sname:VkAllocationCallbacks were provided when pname:image was
    created, pname:pAllocator must: be `NULL`
****

include::../validity/protos/vkDestroyImage.txt[]


[[resources-image-layouts]]
== Image Layouts

Images are stored in implementation-dependent opaque layouts in memory.
Implementations may: support several opaque layouts, and the layout used at
any given time is determined by the elink:VkImageLayout state of the image
subresource.
Each layout has limitations on what kinds of operations are supported for
image subresources using the layout.
Applications have control over which layout each image subresource uses, and
can: transition an image subresource from one layout to another.
Transitions can: happen with an image memory barrier, included as part of a
fname:vkCmdPipelineBarrier or a fname:vkCmdWaitEvents command buffer command
(see <<synchronization-image-memory-barrier>>), or as part of a subpass
dependency within a render pass (see sname:VkSubpassDependency).
The image layout state is per-image subresource, and separate image
subresources of the same image can: be in different layouts at the same time
with one exception - depth and stencil aspects of a given image subresource
must: always be in the same layout.

[NOTE]
.Note
====
Each layout may: offer optimal performance for a specific usage of image
memory.
For example, an image with a layout of
ename:VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL may: provide optimal
performance for use as a color attachment, but be unsupported for use in
transfer commands.
Applications can: transition an image subresource from one layout to another
in order to achieve optimal performance when the image subresource is used
for multiple kinds of operations.
After initialization, applications need not use any layout other than the
general layout, though this may: produce suboptimal performance on some
implementations.
====

Upon creation, all image subresources of an image are initially in the same
layout, where that layout is selected by the
sname:VkImageCreateInfo::pname:initialLayout member.
The pname:initialLayout must: be either ename:VK_IMAGE_LAYOUT_UNDEFINED or
ename:VK_IMAGE_LAYOUT_PREINITIALIZED.
If it is ename:VK_IMAGE_LAYOUT_PREINITIALIZED, then the image data can: be
preinitialized by the host while using this layout, and the transition away
from this layout will preserve that data.
If it is ename:VK_IMAGE_LAYOUT_UNDEFINED, then the contents of the data are
considered to be undefined, and the transition away from this layout is not
guaranteed to preserve that data.
For either of these initial layouts, any image subresources must: be
transitioned to another layout before they are accessed by the device.

Host access to image memory is only well-defined for images created with
ename:VK_IMAGE_TILING_LINEAR tiling and for image subresources of those
images which are currently in either the
ename:VK_IMAGE_LAYOUT_PREINITIALIZED or ename:VK_IMAGE_LAYOUT_GENERAL
layout.
Calling flink:vkGetImageSubresourceLayout for a linear image returns a
subresource layout mapping that is valid for either of those image layouts.

// refBegin VkImageLayout Layout of image and image subresources

The set of image layouts consists of:

include::../api/enums/VkImageLayout.txt[]

The type(s) of device access supported by each layout are:

  * ename:VK_IMAGE_LAYOUT_UNDEFINED: Supports no device access.
    This layout must: only be used as the pname:initialLayout member of
    sname:VkImageCreateInfo or sname:VkAttachmentDescription, or as the
    pname:oldLayout in an image transition.
    When transitioning out of this layout, the contents of the memory are
    not guaranteed to be preserved.
  * ename:VK_IMAGE_LAYOUT_PREINITIALIZED: Supports no device access.
    This layout must: only be used as the pname:initialLayout member of
    sname:VkImageCreateInfo or sname:VkAttachmentDescription, or as the
    pname:oldLayout in an image transition.
    When transitioning out of this layout, the contents of the memory are
    preserved.
    This layout is intended to be used as the initial layout for an image
    whose contents are written by the host, and hence the data can: be
    written to memory immediately, without first executing a layout
    transition.
    Currently, ename:VK_IMAGE_LAYOUT_PREINITIALIZED is only useful with
    ename:VK_IMAGE_TILING_LINEAR images because there is not a standard
    layout defined for ename:VK_IMAGE_TILING_OPTIMAL images.
  * ename:VK_IMAGE_LAYOUT_GENERAL: Supports all types of device access.
  * ename:VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL: must: only be used as a
    color or resolve attachment in a sname:VkFramebuffer.
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT usage bit enabled.
  * ename:VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL: must: only be
    used as a depth/stencil attachment in a sname:VkFramebuffer.
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT usage bit enabled.
  * ename:VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL: must: only be
    used as a read-only depth/stencil attachment in a sname:VkFramebuffer
    and/or as a read-only image in a shader (which can: be read as a sampled
    image, combined image/sampler and/or input attachment).
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT usage bit enabled.
    Only image subresources of images created with
    ename:VK_IMAGE_USAGE_SAMPLED_BIT can: be used as sampled image or
    combined image/sampler in a shader.
    Similarly, only image subresources of images created with
    ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT can: be used as input
    attachments.
  * ename:VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL: must: only be used as a
    read-only image in a shader (which can: be read as a sampled image,
    combined image/sampler and/or input attachment).
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_SAMPLED_BIT or
    ename:VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT usage bit enabled.
  * ename:VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL: must: only be used as a
    source image of a transfer command (see the definition of
    <<synchronization-transfer,ename:VK_PIPELINE_STAGE_TRANSFER_BIT>>).
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_TRANSFER_SRC_BIT usage bit enabled.
  * ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL: must: only be used as a
    destination image of a transfer command.
    This layout is valid only for image subresources of images created with
    the ename:VK_IMAGE_USAGE_TRANSFER_DST_BIT usage bit enabled.
ifdef::VK_KHR_swapchain[]
  * ename:VK_IMAGE_LAYOUT_PRESENT_SRC_KHR: must: only be used for presenting
    a swapchain image for display.
    A swapchain's image must: be transitioned to this layout before calling
    flink:vkQueuePresentKHR, and must: be transitioned away from this layout
    after calling flink:vkAcquireNextImageKHR.
endif::VK_KHR_swapchain[]

For each mechanism of accessing an image in the API, there is a parameter or
structure member that controls the image layout used to access the image.
For transfer commands, this is a parameter to the command (see <<clears>>
and <<copies>>).
For use as a framebuffer attachment, this is a member in the substructures
of the sname:VkRenderPassCreateInfo (see <<renderpass,Render Pass>>).
For use in a descriptor set, this is a member in the
sname:VkDescriptorImageInfo structure (see <<descriptorsets-updates>>).
At the time that any command buffer command accessing an image executes on
any queue, the layouts of the image subresources that are accessed must: all
match the layout specified via the API controlling those accesses.

The image layout of each image subresource must: be well-defined at each
point in the image subresource's lifetime.
This means that when performing a layout transition on the image
subresource, the old layout value must: either equal the current layout of
the image subresource (at the time the transition executes), or else be
ename:VK_IMAGE_LAYOUT_UNDEFINED (implying that the contents of the image
subresource need not be preserved).
The new layout used in a transition must: not be
ename:VK_IMAGE_LAYOUT_UNDEFINED or ename:VK_IMAGE_LAYOUT_PREINITIALIZED.

// refEnd VkImageLayout


[[resources-image-views]]
== Image Views

// refBegin VkImageView Opaque handle to a image view object

Image objects are not directly accessed by pipeline shaders for reading or
writing image data.
Instead, _image views_ representing contiguous ranges of the image
subresources and containing additional metadata are used for that purpose.
Views must: be created on images of compatible types, and must: represent a
valid subset of image subresources.

Image views are represented by sname:VkImageView handles:

include::../api/handles/VkImageView.txt[]

// refEnd VkImageView

// refBegin VkImageViewType Image view types

The types of image views that can: be created are:

include::../api/enums/VkImageViewType.txt[]

The exact image view type is partially implicit, based on the image's type
and sample count, as well as the view creation parameters as described in
the <<resources-image-views-compatibility,table below>>.
This table also shows which SPIR-V OpTypeImage Dim and Arrayed parameters
correspond to each image view type.

// refEnd VkImageViewType

// refBegin vkCreateImageView Create an image view from an existing image

To create an image view, call:

include::../api/protos/vkCreateImageView.txt[]

  * pname:device is the logical device that creates the image view.
  * pname:pCreateInfo is a pointer to an instance of the
    sname:VkImageViewCreateInfo structure containing parameters to be used
    to create the image view.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.
  * pname:pView points to a sname:VkImageView handle in which the resulting
    image view object is returned.

Some of the image creation parameters are inherited by the view.
The remaining parameters are contained in the pname:pCreateInfo.

include::../validity/protos/vkCreateImageView.txt[]

// refBegin VkImageViewCreateInfo Structure specifying parameters of a newly created image view

The sname:VkImageViewCreateInfo structure is defined as:

include::../api/structs/VkImageViewCreateInfo.txt[]

  * pname:sType is the type of this structure.
  * pname:pNext is `NULL` or a pointer to an extension-specific structure.
  * pname:flags is reserved for future use.
  * pname:image is a sname:VkImage on which the view will be created.
  * pname:viewType is the type of the image view.
  * pname:format is a elink:VkFormat describing the format and type used to
    interpret data elements in the image.
  * pname:components specifies a remapping of color components (or of depth
    or stencil components after they have been converted into color
    components).
    See slink:VkComponentMapping.
  * pname:subresourceRange is a slink:VkImageSubresourceRange selecting the
    set of mipmap levels and array layers to be accessible to the view.

If pname:image was created with the ename:VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT
flag, pname:format can: be different from the image's format, but if they
are not equal they must: be _compatible_.
Image format compatibility is defined in the
<<features-formats-compatibility-classes,Format Compatibility Classes>>
section.

[[resources-image-views-compatibility]]
.Image and image view parameter compatibility requirements
[cols="15%h,35%,50%",options="header"]
|====
| Dim, Arrayed, MS | Image parameters | View parameters
| | pname:imageType = ci.pname:imageType +
    pname:width = ci.pname:extent.width +
    pname:height = ci.pname:extent.height +
    pname:depth = ci.pname:extent.depth +
    pname:arrayLayers = ci.pname:arrayLayers +
    pname:samples = ci.pname:samples +
    where ci is the slink:VkImageCreateInfo used to create pname:image.
  | pname:baseArrayLayer and pname:layerCount are members of the
    pname:subresourceRange member.
| 1D, 0, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_1D +
pname:width {geq} 1 +
pname:height = 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples = 1 |
pname:viewType = ename:VK_VIEW_TYPE_1D +
pname:baseArrayLayer {geq} 0 +
pname:layerCount = 1
| 1D, 1, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_1D +
pname:width {geq} 1 +
pname:height = 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples = 1 |
pname:viewType = ename:VK_VIEW_TYPE_1D_ARRAY +
pname:baseArrayLayer {geq} 0 +
pname:layerCount {geq} 1
| 2D, 0, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height {geq} 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples = 1 |
pname:viewType = ename:VK_VIEW_TYPE_2D +
pname:baseArrayLayer {geq} 0 +
pname:layerCount = 1
| 2D, 1, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height {geq} 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples = 1 |
pname:viewType = ename:VK_VIEW_TYPE_2D_ARRAY +
pname:baseArrayLayer {geq} 0 +
pname:layerCount {geq} 1
| 2D, 0, 1 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height {geq} 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples > 1 |
pname:viewType = ename:VK_VIEW_TYPE_2D +
pname:baseArrayLayer {geq} 0 +
pname:layerCount = 1
| 2D, 1, 1 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height {geq} 1 +
pname:depth = 1 +
pname:arrayLayers {geq} 1 +
pname:samples > 1 |
pname:viewType = ename:VK_VIEW_TYPE_2D_ARRAY +
pname:baseArrayLayer {geq} 0 +
pname:layerCount {geq} 1
| CUBE, 0, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height = pname:width +
pname:depth = 1 +
pname:arrayLayers {geq} 6 +
pname:samples = 1 +
pname:flags includes ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT |
pname:viewType = ename:VK_VIEW_TYPE_CUBE +
pname:baseArrayLayer {geq} 0 +
pname:layerCount = 6
| CUBE, 1, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_2D +
pname:width {geq} 1 +
pname:height = width +
pname:depth = 1 +
_N_ {geq} 1 +
pname:arrayLayers {geq} 6 {times} _N_ +
pname:samples = 1 +
pname:flags includes ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT |
pname:viewType = ename:VK_VIEW_TYPE_CUBE_ARRAY +
pname:baseArrayLayer {geq} 0 +
pname:layerCount = 6 {times} _N_, _N_ {geq} 1
| 3D, 0, 0 |
pname:imageType = ename:VK_IMAGE_TYPE_3D +
pname:width {geq} 1 +
pname:height {geq} 1 +
pname:depth {geq} 1 +
pname:arrayLayers = 1 +
pname:samples = 1 |
pname:viewType = ename:VK_VIEW_TYPE_3D +
pname:baseArrayLayer = 0 +
pname:layerCount = 1
|====

.Valid Usage
****
  * If pname:image was not created with
    ename:VK_IMAGE_CREATE_CUBE_COMPATIBLE_BIT then pname:viewType must: not
    be ename:VK_IMAGE_VIEW_TYPE_CUBE or ename:VK_IMAGE_VIEW_TYPE_CUBE_ARRAY
  * If the <<features-features-imageCubeArray,image cubemap arrays>> feature
    is not enabled, pname:viewType must: not be
    ename:VK_IMAGE_VIEW_TYPE_CUBE_ARRAY
  * If the <<features-features-textureCompressionETC2,ETC2 texture
    compression>> feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_ETC2_R8G8B8_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8_SRGB_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A1_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A1_SRGB_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A8_UNORM_BLOCK,
    ename:VK_FORMAT_ETC2_R8G8B8A8_SRGB_BLOCK,
    ename:VK_FORMAT_EAC_R11_UNORM_BLOCK,
    ename:VK_FORMAT_EAC_R11_SNORM_BLOCK,
    ename:VK_FORMAT_EAC_R11G11_UNORM_BLOCK, or
    ename:VK_FORMAT_EAC_R11G11_SNORM_BLOCK
  * If the <<features-features-textureCompressionASTC_LDR,ASTC LDR texture
    compression>> feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_ASTC_4x4_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_4x4_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_5x4_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_5x4_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_5x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_5x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_6x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_6x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_6x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_6x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_8x8_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_8x8_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x5_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x5_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x6_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x6_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x8_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x8_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_10x10_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_10x10_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_12x10_UNORM_BLOCK,
    ename:VK_FORMAT_ASTC_12x10_SRGB_BLOCK,
    ename:VK_FORMAT_ASTC_12x12_UNORM_BLOCK, or
    ename:VK_FORMAT_ASTC_12x12_SRGB_BLOCK
  * If the <<features-features-textureCompressionBC,BC texture compression>>
    feature is not enabled, pname:format must: not be
    ename:VK_FORMAT_BC1_RGB_UNORM_BLOCK, ename:VK_FORMAT_BC1_RGB_SRGB_BLOCK,
    ename:VK_FORMAT_BC1_RGBA_UNORM_BLOCK,
    ename:VK_FORMAT_BC1_RGBA_SRGB_BLOCK, ename:VK_FORMAT_BC2_UNORM_BLOCK,
    ename:VK_FORMAT_BC2_SRGB_BLOCK, ename:VK_FORMAT_BC3_UNORM_BLOCK,
    ename:VK_FORMAT_BC3_SRGB_BLOCK, ename:VK_FORMAT_BC4_UNORM_BLOCK,
    ename:VK_FORMAT_BC4_SNORM_BLOCK, ename:VK_FORMAT_BC5_UNORM_BLOCK,
    ename:VK_FORMAT_BC5_SNORM_BLOCK, ename:VK_FORMAT_BC6H_UFLOAT_BLOCK,
    ename:VK_FORMAT_BC6H_SFLOAT_BLOCK, ename:VK_FORMAT_BC7_UNORM_BLOCK, or
    ename:VK_FORMAT_BC7_SRGB_BLOCK
  * If pname:image was created with ename:VK_IMAGE_TILING_LINEAR,
    pname:format must: be format that has at least one supported feature bit
    present in the value of
    sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_LINEAR and
    pname:usage containing ename:VK_IMAGE_USAGE_SAMPLED_BIT, pname:format
    must: be supported for sampled images, as specified by the
    ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_BIT flag in
    sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_LINEAR and
    pname:usage containing ename:VK_IMAGE_USAGE_STORAGE_BIT, pname:format
    must: be supported for storage images, as specified by the
    ename:VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT flag in
    sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_LINEAR and
    pname:usage containing ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
    pname:format must: be supported for color attachments, as specified by
    the ename:VK_FORMAT_FEATURE_COLOR_ATTACHMENT_BIT flag in
    sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_LINEAR and
    pname:usage containing
    ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, pname:format must: be
    supported for depth/stencil attachments, as specified by the
    ename:VK_FORMAT_FEATURE_DEPTH_STENCIL_ATTACHMENT_BIT flag in
    sname:VkFormatProperties::pname:linearTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_OPTIMAL,
    pname:format must: be format that has at least one supported feature bit
    present in the value of
    sname:VkFormatProperties::pname:optimalTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_OPTIMAL and
    pname:usage containing ename:VK_IMAGE_USAGE_SAMPLED_BIT, pname:format
    must: be supported for sampled images, as specified by the
    ename:VK_FORMAT_FEATURE_SAMPLED_IMAGE_BIT flag in
    sname:VkFormatProperties::pname:optimalTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_OPTIMAL and
    pname:usage containing ename:VK_IMAGE_USAGE_STORAGE_BIT, pname:format
    must: be supported for storage images, as specified by the
    ename:VK_FORMAT_FEATURE_STORAGE_IMAGE_BIT flag in
    sname:VkFormatProperties::pname:optimalTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_OPTIMAL and
    pname:usage containing ename:VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
    pname:format must: be supported for color attachments, as specified by
    the ename:VK_FORMAT_FEATURE_COLOR_ATTACHMENT_BIT flag in
    sname:VkFormatProperties::pname:optimalTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * If pname:image was created with ename:VK_IMAGE_TILING_OPTIMAL and
    pname:usage containing
    ename:VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, pname:format must: be
    supported for depth/stencil attachments, as specified by the
    ename:VK_FORMAT_FEATURE_DEPTH_STENCIL_ATTACHMENT_BIT flag in
    sname:VkFormatProperties::pname:optimalTilingFeatures returned by
    fname:vkGetPhysicalDeviceFormatProperties with the same value of
    pname:format
  * pname:subresourceRange must: be a valid image subresource range for
    pname:image (see <<resources-image-views>>)
  * If pname:image was created with the
    ename:VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT flag, pname:format must: be
    compatible with the pname:format used to create pname:image, as defined
    in <<features-formats-compatibility-classes,Format Compatibility
    Classes>>
  * If pname:image was not created with the
    ename:VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT flag, pname:format must: be
    identical to the pname:format used to create pname:image
  * pname:subResourceRange and pname:viewType must: be compatible with the
    image, as described in the
    <<resources-image-views-compatibility,compatibility table>>
****

include::../validity/structs/VkImageViewCreateInfo.txt[]

// refBegin VkImageSubresourceRange Structure specifying a image subresource range

The sname:VkImageSubresourceRange structure is defined as:

include::../api/structs/VkImageSubresourceRange.txt[]

  * pname:aspectMask is a bitmask indicating which aspect(s) of the image
    are included in the view.
    See elink:VkImageAspectFlagBits.
  * pname:baseMipLevel is the first mipmap level accessible to the view.
  * pname:levelCount is the number of mipmap levels (starting from
    pname:baseMipLevel) accessible to the view.
  * pname:baseArrayLayer is the first array layer accessible to the view.
  * pname:layerCount is the number of array layers (starting from
    pname:baseArrayLayer) accessible to the view.

The number of mipmap levels and array layers must: be a subset of the image
subresources in the image.
If an application wants to use all mip levels or layers in an image after
the pname:baseMipLevel or pname:baseArrayLayer, it can: set pname:levelCount
and pname:layerCount to the special values ename:VK_REMAINING_MIP_LEVELS and
ename:VK_REMAINING_ARRAY_LAYERS without knowing the exact number of mip
levels or layers.

For cube and cube array image views, the layers of the image view starting
at pname:baseArrayLayer correspond to faces in the order +X, -X, +Y, -Y, +Z,
-Z.
For cube arrays, each set of six sequential layers is a single cube, so the
number of cube maps in a cube map array view is _pname:layerCount / 6_, and
image array layer _pname:baseArrayLayer + i_ is face index _i mod 6_ of cube
_i / 6_.
If the number of layers in the view, whether set explicitly in
pname:layerCount or implied by ename:VK_REMAINING_ARRAY_LAYERS, is not a
multiple of 6, behavior when indexing the last cube is undefined.

pname:aspectMask is a bitmask indicating the format being used.
Bits which may: be set include:

// refBegin VkImageAspectFlagBits Bitmask specifying which aspects of an image are included in a view
include::../api/enums/VkImageAspectFlagBits.txt[]

The mask must: be only ename:VK_IMAGE_ASPECT_COLOR_BIT,
ename:VK_IMAGE_ASPECT_DEPTH_BIT or ename:VK_IMAGE_ASPECT_STENCIL_BIT if
pname:format is a color, depth-only or stencil-only format, respectively.
If using a depth/stencil format with both depth and stencil components,
pname:aspectMask must: include at least one of
ename:VK_IMAGE_ASPECT_DEPTH_BIT and ename:VK_IMAGE_ASPECT_STENCIL_BIT, and
can: include both.

When using an imageView of a depth/stencil image to populate a descriptor
set (e.g. for sampling in the shader, or for use as an input attachment),
the pname:aspectMask must: only include one bit and selects whether the
imageView is used for depth reads (i.e. using a floating-point sampler or
input attachment in the shader) or stencil reads (i.e. using an unsigned
integer sampler or input attachment in the shader).
When an imageView of a depth/stencil image is used as a depth/stencil
framebuffer attachment, the pname:aspectMask is ignored and both depth and
stencil image subresources are used.

The pname:components member is of type slink:VkComponentMapping, and
describes a remapping from components of the image to components of the
vector returned by shader image instructions.
This remapping must: be identity for storage image descriptors, input
attachment descriptors, and framebuffer attachments.

.Valid Usage
****
  * If pname:levelCount is not ename:VK_REMAINING_MIP_LEVELS,
    [eq]#(pname:baseMipLevel + pname:levelCount)# must: be less than or
    equal to the pname:mipLevels specified in slink:VkImageCreateInfo when
    the image was created
  * If pname:layerCount is not ename:VK_REMAINING_ARRAY_LAYERS,
    [eq]#(pname:baseArrayLayer + pname:layerCount)# must: be less than or
    equal to the pname:arrayLayers specified in slink:VkImageCreateInfo when
    the image was created
****

include::../validity/structs/VkImageSubresourceRange.txt[]

// refBegin VkComponentMapping Structure specifying a color component mapping

The sname:VkComponentMapping structure is defined as:

include::../api/structs/VkComponentMapping.txt[]

  * pname:r determines the component value placed in the R component of the
    output vector.
  * pname:g determines the component value placed in the G component of the
    output vector.
  * pname:b determines the component value placed in the B component of the
    output vector.
  * pname:a determines the component value placed in the A component of the
    output vector.

Each of pname:r, pname:g, pname:b, and pname:a is one of the values:

// refBegin VkComponentSwizzle Specify how a component is swizzled
include::../api/enums/VkComponentSwizzle.txt[]

  * ename:VK_COMPONENT_SWIZZLE_IDENTITY: the component is set to the
    identity swizzle.
  * ename:VK_COMPONENT_SWIZZLE_ZERO: the component is set to zero.
  * ename:VK_COMPONENT_SWIZZLE_ONE: the component is set to either 1 or 1.0
    depending on whether the type of the image view format is integer or
    floating-point respectively, as determined by the
    <<features-formats-definition,Format Definition>> section for each
    elink:VkFormat.
  * ename:VK_COMPONENT_SWIZZLE_R: the component is set to the value of the R
    component of the image.
  * ename:VK_COMPONENT_SWIZZLE_G: the component is set to the value of the G
    component of the image.
  * ename:VK_COMPONENT_SWIZZLE_B: the component is set to the value of the B
    component of the image.
  * ename:VK_COMPONENT_SWIZZLE_A: the component is set to the value of the A
    component of the image.

Setting the identity swizzle on a component is equivalent to setting the
identity mapping on that component.
That is:

[[resources-image-views-identity-mappings]]
.Component Mappings Equivalent To ename:VK_COMPONENT_SWIZZLE_IDENTITY
[options="header"]
|====
| Component          | Identity Mapping
| pname:components.r | ename:VK_COMPONENT_SWIZZLE_R
| pname:components.g | ename:VK_COMPONENT_SWIZZLE_G
| pname:components.b | ename:VK_COMPONENT_SWIZZLE_B
| pname:components.a | ename:VK_COMPONENT_SWIZZLE_A
|====

include::../validity/structs/VkComponentMapping.txt[]

// refBegin vkDestroyImageView Destroy an image view object

To destroy an image view, call:

include::../api/protos/vkDestroyImageView.txt[]

  * pname:device is the logical device that destroys the image view.
  * pname:imageView is the image view to destroy.
  * pname:pAllocator controls host memory allocation as described in the
    <<memory-allocation, Memory Allocation>> chapter.

.Valid Usage
****
  * All submitted commands that refer to pname:imageView must: have
    completed execution
  * If sname:VkAllocationCallbacks were provided when pname:imageView was
    created, a compatible set of callbacks must: be provided here
  * If no sname:VkAllocationCallbacks were provided when pname:imageView was
    created, pname:pAllocator must: be `NULL`
****

include::../validity/protos/vkDestroyImageView.txt[]


[[resources-association]]
== Resource Memory Association

Resources are initially created as _virtual allocations_ with no backing
memory.
Device memory is allocated separately (see <<memory-device>>) and then
associated with the resource.
This association is done differently for sparse and non-sparse resources.

Resources created with any of the sparse creation flags are considered
sparse resources.
Resources created without these flags are non-sparse.
The details on resource memory association for sparse resources is described
in <<sparsememory>>.

Non-sparse resources must: be bound completely and contiguously to a single
sname:VkDeviceMemory object before the resource is passed as a parameter to
any of the following operations:

  * creating image or buffer views
  * updating descriptor sets
  * recording commands in a command buffer

Once bound, the memory binding is immutable for the lifetime of the
resource.

// refBegin vkGetBufferMemoryRequirements Returns the memory requirements for specified Vulkan object

To determine the memory requirements for a buffer resource, call:

include::../api/protos/vkGetBufferMemoryRequirements.txt[]

  * pname:device is the logical device that owns the buffer.
  * pname:buffer is the buffer to query.
  * pname:pMemoryRequirements points to an instance of the
    slink:VkMemoryRequirements structure in which the memory requirements of
    the buffer object are returned.

include::../validity/protos/vkGetBufferMemoryRequirements.txt[]

// refBegin vkGetImageMemoryRequirements Returns the memory requirements for specified Vulkan object

To determine the memory requirements for an image resource, call:

include::../api/protos/vkGetImageMemoryRequirements.txt[]

  * pname:device is the logical device that owns the image.
  * pname:image is the image to query.
  * pname:pMemoryRequirements points to an instance of the
    slink:VkMemoryRequirements structure in which the memory requirements of
    the image object are returned.

include::../validity/protos/vkGetImageMemoryRequirements.txt[]

// refBegin VkMemoryRequirements Structure specifying memory requirements

The sname:VkMemoryRequirements structure is defined as:

include::../api/structs/VkMemoryRequirements.txt[]

  * pname:size is the size, in bytes, of the memory allocation required: for
    the resource.
  * pname:alignment is the alignment, in bytes, of the offset within the
    allocation required: for the resource.
  * pname:memoryTypeBits is a bitmask and contains one bit set for every
    supported memory type for the resource.
    Bit `i` is set if and only if the memory type `i` in the
    sname:VkPhysicalDeviceMemoryProperties structure for the physical device
    is supported for the resource.

include::../validity/structs/VkMemoryRequirements.txt[]

The implementation guarantees certain properties about the memory
requirements returned by flink:vkGetBufferMemoryRequirements and
flink:vkGetImageMemoryRequirements:

  * The pname:memoryTypeBits member always contains at least one bit set.
  * If pname:buffer is a sname:VkBuffer not created with the
    ename:VK_BUFFER_CREATE_SPARSE_BINDING_BIT bit set, or if pname:image is
    a sname:VkImage that was created with a ename:VK_IMAGE_TILING_LINEAR
    value in the pname:tiling member of the sname:VkImageCreateInfo
    structure passed to fname:vkCreateImage, then the pname:memoryTypeBits
    member always contains at least one bit set corresponding to a
    sname:VkMemoryType with a pname:propertyFlags that has both the
    ename:VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT bit and the
    ename:VK_MEMORY_PROPERTY_HOST_COHERENT_BIT bit set.
    In other words, mappable coherent memory can: always be attached to
    these objects.
  * The pname:memoryTypeBits member always contains at least one bit set
    corresponding to a sname:VkMemoryType with a pname:propertyFlags that
    has the ename:VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT bit set.
  * The pname:memoryTypeBits member is identical for all sname:VkBuffer
    objects created with the same value for the pname:flags and pname:usage
    members in the sname:VkBufferCreateInfo structure passed to
    fname:vkCreateBuffer.
    Further, if code:usage1 and code:usage2 of type elink:VkBufferUsageFlags
    are such that the bits set in code:usage2 are a subset of the bits set
    in code:usage1, and they have the same pname:flags, then the bits set in
    pname:memoryTypeBits returned for code:usage1 must: be a subset of the
    bits set in pname:memoryTypeBits returned for code:usage2, for all
    values of pname:flags.
  * The pname:alignment member is identical for all sname:VkBuffer objects
    created with the same combination of values for the pname:usage and
    pname:flags members in the sname:VkBufferCreateInfo structure passed to
    fname:vkCreateBuffer.
  * The pname:memoryTypeBits member is identical for all sname:VkImage
    objects created with the same combination of values for the pname:tiling
    member and the ename:VK_IMAGE_CREATE_SPARSE_BINDING_BIT bit of the
    pname:flags member and the ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT
    of the pname:usage member in the sname:VkImageCreateInfo structure
    passed to fname:vkCreateImage.
  * If the memory requirements are for a sname:VkImage, the
    pname:memoryTypeBits member must: not refer to a sname:VkMemoryType with
    a pname:propertyFlags that has the
    ename:VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT bit set if the
    flink:vkGetImageMemoryRequirements::pname:image did not have
    ename:VK_IMAGE_USAGE_TRANSIENT_ATTACHMENT_BIT bit set in the pname:usage
    member of the sname:VkImageCreateInfo structure passed to
    fname:vkCreateImage.
  * If the memory requirements are for a sname:VkBuffer, the
    pname:memoryTypeBits member must: not refer to a sname:VkMemoryType with
    a pname:propertyFlags that has the
    ename:VK_MEMORY_PROPERTY_LAZILY_ALLOCATED_BIT bit set.
+
--
[NOTE]
.Note
====
The implication of this requirement is that lazily allocated memory is
disallowed for buffers in all cases.
====
--

// refBegin vkBindBufferMemory Bind device memory to a buffer object

To attach memory to a buffer object, call:

include::../api/protos/vkBindBufferMemory.txt[]

  * pname:device is the logical device that owns the buffer and memory.
  * pname:buffer is the buffer.
  * pname:memory is a sname:VkDeviceMemory object describing the device
    memory to attach.
  * pname:memoryOffset is the start offset of the region of pname:memory
    which is to be bound to the buffer.
    The number of bytes returned in the
    sname:VkMemoryRequirements::pname:size member in pname:memory, starting
    from pname:memoryOffset bytes, will be bound to the specified buffer.

.Valid Usage
****
  * pname:buffer must: not already be backed by a memory object
  * pname:buffer must: not have been created with any sparse memory binding
    flags
  * pname:memoryOffset must: be less than the size of pname:memory
  * If pname:buffer was created with the
    ename:VK_BUFFER_USAGE_UNIFORM_TEXEL_BUFFER_BIT or
    ename:VK_BUFFER_USAGE_STORAGE_TEXEL_BUFFER_BIT, pname:memoryOffset must:
    be a multiple of
    sname:VkPhysicalDeviceLimits::pname:minTexelBufferOffsetAlignment
  * If pname:buffer was created with the
    ename:VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT, pname:memoryOffset must: be a
    multiple of
    sname:VkPhysicalDeviceLimits::pname:minUniformBufferOffsetAlignment
  * If pname:buffer was created with the
    ename:VK_BUFFER_USAGE_STORAGE_BUFFER_BIT, pname:memoryOffset must: be a
    multiple of
    sname:VkPhysicalDeviceLimits::pname:minStorageBufferOffsetAlignment
  * pname:memory must: have been allocated using one of the memory types
    allowed in the pname:memoryTypeBits member of the
    sname:VkMemoryRequirements structure returned from a call to
    fname:vkGetBufferMemoryRequirements with pname:buffer
  * pname:memoryOffset must: be an integer multiple of the pname:alignment
    member of the sname:VkMemoryRequirements structure returned from a call
    to fname:vkGetBufferMemoryRequirements with pname:buffer
  * The pname:size member of the sname:VkMemoryRequirements structure
    returned from a call to fname:vkGetBufferMemoryRequirements with
    pname:buffer must: be less than or equal to the size of pname:memory
    minus pname:memoryOffset
ifdef::VK_NV_dedicated_allocation[]
  * If pname:buffer was created with
    sname:VkDedicatedAllocationBufferCreateInfoNV::pname:dedicatedAllocation
    equal to ename:VK_TRUE, pname:memory must: have been created with
    sname:VkDedicatedAllocationMemoryAllocateInfoNV::pname:buffer equal to
    pname:buffer and pname:memoryOffset must: be zero
  * If pname:buffer was not created with
    sname:VkDedicatedAllocationBufferCreateInfoNV::pname:dedicatedAllocation
    equal to ename:VK_TRUE, pname:memory must: not have been allocated
    dedicated for a specific buffer or image
endif::VK_NV_dedicated_allocation[]
****

include::../validity/protos/vkBindBufferMemory.txt[]

// refBegin vkBindImageMemory Bind device memory to an image object

To attach memory to an image object, call:

include::../api/protos/vkBindImageMemory.txt[]

  * pname:device is the logical device that owns the image and memory.
  * pname:image is the image.
  * pname:memory is the a sname:VkDeviceMemory object describing the device
    memory to attach.
  * pname:memoryOffset is the start offset of the region of pname:memory
    which is to be bound to the image.
    The number of bytes returned in the
    sname:VkMemoryRequirements::pname:size member in pname:memory, starting
    from pname:memoryOffset bytes, will be bound to the specified image.

.Valid Usage
****
  * pname:image must: not already be backed by a memory object
  * pname:image must: not have been created with any sparse memory binding
    flags
  * pname:memoryOffset must: be less than the size of pname:memory
  * pname:memory must: have been allocated using one of the memory types
    allowed in the pname:memoryTypeBits member of the
    sname:VkMemoryRequirements structure returned from a call to
    fname:vkGetImageMemoryRequirements with pname:image
  * pname:memoryOffset must: be an integer multiple of the pname:alignment
    member of the sname:VkMemoryRequirements structure returned from a call
    to fname:vkGetImageMemoryRequirements with pname:image
  * The pname:size member of the sname:VkMemoryRequirements structure
    returned from a call to fname:vkGetImageMemoryRequirements with
    pname:image must: be less than or equal to the size of pname:memory
    minus pname:memoryOffset
ifdef::VK_NV_dedicated_allocation[]
  * If pname:image was created with
    sname:VkDedicatedAllocationImageCreateInfoNV::pname:dedicatedAllocation
    equal to ename:VK_TRUE, pname:memory must: have been created with
    sname:VkDedicatedAllocationMemoryAllocateInfoNV::pname:image equal to
    pname:image and pname:memoryOffset must: be zero
  * If pname:image was not created with
    sname:VkDedicatedAllocationImageCreateInfoNV::pname:dedicatedAllocation
    equal to ename:VK_TRUE, pname:memory must: not have been allocated
    dedicated for a specific buffer or image
endif::VK_NV_dedicated_allocation[]
****

include::../validity/protos/vkBindImageMemory.txt[]

[[resources-bufferimagegranularity,Buffer-Image Granularity]]
.Buffer-Image Granularity
There is an implementation-dependent limit, pname:bufferImageGranularity,
which specifies a page-like granularity at which buffer, linear image and
optimal image resources must: be placed in adjacent memory locations to
avoid aliasing.
Two resources which do not satisfy this granularity requirement are said to
<<resources-memory-aliasing,alias>>.
Linear image resource are images created with ename:VK_IMAGE_TILING_LINEAR
and optimal image resources are those created with
ename:VK_IMAGE_TILING_OPTIMAL.
pname:bufferImageGranularity is specified in bytes, and must: be a power of
two.
Implementations which do not require such an additional granularity may:
report a value of one.

[NOTE]
.Note
====
pname:bufferImageGranularity is really a granularity between "linear"
resources, including buffers and images with linear tiling, vs.
"optimal" resources, i.e. images with optimal tiling.
It would have been better named "linearOptimalGranularity".
====

Given resourceA at the lower memory offset and resourceB at the higher
memory offset in the same sname:VkDeviceMemory object, where one of the
resources is a buffer or a linear image and the other is an optimal image,
and the following:

[source,c]
---------------------------------------------------
resourceA.end       = resourceA.memoryOffset + resourceA.size - 1
resourceA.endPage   = resourceA.end & ~(bufferImageGranularity-1)
resourceB.start     = resourceB.memoryOffset
resourceB.startPage = resourceB.start & ~(bufferImageGranularity-1)
---------------------------------------------------

The following property must: hold:

[source,c]
---------------------------------------------------
resourceA.endPage < resourceB.startPage
---------------------------------------------------

That is, the end of the first resource (A) and the beginning of the second
resource (B) must: be on separate ``pages'' of size
pname:bufferImageGranularity.
pname:bufferImageGranularity may: be different than the physical page size
of the memory heap.
This restriction is only needed when a buffer or a linear image is at
adjacent memory location with an optimal image and both will be used
simultaneously.
Adjacent buffers' or adjacent images' memory ranges can: be closer than
pname:bufferImageGranularity, provided they meet the pname:alignment
requirement for the objects in question.

Sparse block size in bytes and sparse image and buffer memory alignments
must: all be multiples of the pname:bufferImageGranularity.
Therefore, memory bound to sparse resources naturally satisfies the
pname:bufferImageGranularity.

[[resources-sharing]]
== Resource Sharing Mode

// refBegin VkSharingMode Buffer and image sharing modes

Buffer and image objects are created with a _sharing mode_ controlling how
they can: be accessed from queues.
The supported sharing modes are:

include::../api/enums/VkSharingMode.txt[]

  * ename:VK_SHARING_MODE_EXCLUSIVE specifies that access to any range or
    image subresource of the object will be exclusive to a single queue
    family at a time.
  * ename:VK_SHARING_MODE_CONCURRENT specifies that concurrent access to any
    range or image subresource of the object from multiple queue families is
    supported.

[NOTE]
.Note
====
ename:VK_SHARING_MODE_CONCURRENT may: result in lower performance access to
the buffer or image than ename:VK_SHARING_MODE_EXCLUSIVE.
====

Ranges of buffers and image subresources of image objects created using
ename:VK_SHARING_MODE_EXCLUSIVE must: only be accessed by queues in the same
queue family at any given time.
In order for a different queue family to be able to interpret the memory
contents of a range or image subresource, the application must: transfer
exclusive ownership of the range or image subresource between the source and
destination queue families with the following sequence of operations:

  . Release exclusive ownership from the source queue family to the
    destination queue family.
  . Use semaphores to ensure proper execution control for the ownership
    transfer.
  . Acquire exclusive ownership for the destination queue family from the
    source queue family.

To release exclusive ownership of a range of a buffer or image subresource
of an image object, the application must: execute a buffer or image memory
barrier, respectively (see slink:VkBufferMemoryBarrier and
slink:VkImageMemoryBarrier) on a queue from the source queue family.
The pname:srcQueueFamilyIndex parameter of the barrier must: be set to the
source queue family index, and the pname:dstQueueFamilyIndex parameter to
the destination queue family index.

To acquire exclusive ownership, the application must: execute the same
buffer or image memory barrier (i.e. an identically defined instance of the
slink:VkBufferMemoryBarrier or slink:VkImageMemoryBarrier structure that was
used for the exclusive ownership release) on a queue from the destination
queue family.

Upon creation, resources using ename:VK_SHARING_MODE_EXCLUSIVE are not owned
by any queue family.
A buffer or image memory barrier is not required to acquire ownership when
no queue family owns the resource - it is implicitly acquired upon first use
within a queue.
However, images still require a <<resources-image-layouts,layout
transition>> from ename:VK_IMAGE_LAYOUT_UNDEFINED or
ename:VK_IMAGE_LAYOUT_PREINITIALIZED before being used on the first queue.
This layout transition can: either be accomplished by an image memory
barrier or by use in a render pass instance.

Once a queue family has used a range or image subresource of an
ename:VK_SHARING_MODE_EXCLUSIVE resource, its contents are undefined to
other queue families unless ownership is transferred.
The contents may: also become undefined for other reasons, e.g. as a result
of writes to an image subresource that aliases the same memory.
A queue family can: take ownership of a range or image subresource without
an ownership transfer in the same way as for a resource that was just
created, however doing so means any contents written by other queue families
or via incompatible aliases are undefined.

// refEnd VkSharingMode


[[resources-memory-aliasing]]
== Memory Aliasing

A range of a sname:VkDeviceMemory allocation is _aliased_ if it is bound to
multiple resources simultaneously, via flink:vkBindImageMemory,
flink:vkBindBufferMemory, or via <<sparsememory-resource-binding,sparse
memory bindings>>.
A memory range aliased between two images or two buffers is defined to be
the intersection of the memory ranges bound to the two resources.
A memory range aliased between two resources where one is a buffer or a
linear image, and the other is an optimal image, is defined to be the
intersection of the memory ranges bound to the two resources, where each
range is first padded to be aligned to the pname:bufferImageGranularity.
Applications can: alias memory, but use of multiple aliases is subject to
several constraints.

[NOTE]
.Note
====
Memory aliasing can: be useful to reduce the total device memory footprint
of an application, if some large resources are used for disjoint periods of
time.
====

When an opaque, non-ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT image is
bound to an aliased range, all image subresources of the image _overlap_ the
range.
When a linear image is bound to an aliased range, the image subresources
that (according to the image's advertised layout) include bytes from the
aliased range overlap the range.
When a ename:VK_IMAGE_CREATE_SPARSE_RESIDENCY_BIT image has sparse image
blocks bound to an aliased range, only image subresources including those
sparse image blocks overlap the range, and when the memory bound to the
image's mip tail overlaps an aliased range all image subresources in the mip
tail overlap the range.

Buffers, and linear image subresources in either the
ename:VK_IMAGE_LAYOUT_PREINITIALIZED or ename:VK_IMAGE_LAYOUT_GENERAL
layouts, are _host-accessible subresources_.
That is, the host has a well-defined addressing scheme to interpret the
contents, and thus the layout of the data in memory can: be consistently
interpreted across aliases if each of those aliases is a host-accessible
subresource.
Opaque images and linear image subresources in other layouts are not
host-accessible.

If two aliases are both host-accessible, then they interpret the contents of
the memory in consistent ways, and data written to one alias can: be read by
the other alias.

If either of two aliases is not host-accessible, then the aliases interpret
the contents of the memory differently, and writes via one alias make the
contents of memory partially or completely undefined to the other alias.
If the first alias is a host-accessible subresource, then the bytes affected
are those written by the memory operations according to its addressing
scheme.
If the first alias is not host-accessible, then the bytes affected are those
overlapped by the image subresources that were written.
If the second alias is a host-accessible subresource, the affected bytes
become undefined.
If the second alias is a not host-accessible, all sparse image blocks (for
sparse partially-resident images) or all image subresources (for non-sparse
image and fully resident sparse images) that overlap the affected bytes
become undefined.

If any image subresources are made undefined due to writes to an alias, then
each of those image subresources must: have its layout transitioned from
ename:VK_IMAGE_LAYOUT_UNDEFINED to a valid layout before it is used, or from
ename:VK_IMAGE_LAYOUT_PREINITIALIZED if the memory has been written by the
host.
If any sparse blocks of a sparse image have been made undefined, then only
the image subresources containing them must: be transitioned.

Use of an overlapping range by two aliases must: be separated by a memory
dependency using the appropriate access types if at least one of those uses
performs writes, whether the aliases interpret memory consistently or not.
If buffer or image memory barriers are used, the scope of the barrier must:
contain the entire range and/or set of image subresources that overlap.

If two aliasing image views are used in the same framebuffer, then the
render pass must: declare the attachments using the
<<renderpass-aliasing,ename:VK_ATTACHMENT_DESCRIPTION_MAY_ALIAS_BIT>>, and
follow the other rules listed in that section.

Access to resources which alias memory from shaders using variables
decorated with code:Coherent are not automatically coherent with each other.

[NOTE]
.Note
====
Memory recycled via an application suballocator (i.e. without freeing and
reallocating the memory objects) is not substantially different from memory
aliasing.
However, a suballocator usually waits on a fence before recycling a region
of memory, and signaling a fence involves sufficient implicit dependencies
to satisfy all the above requirements.
====