19. Copy Commands
An application can copy buffer and image data using several methods
depending on the type of data transfer.
Data can be copied between buffer objects with vkCmdCopyBuffer
and a
portion of an image can be copied to another image with
vkCmdCopyImage
.
Image data can also be copied to and from buffer memory using
vkCmdCopyImageToBuffer
and vkCmdCopyBufferToImage
.
Image data can be blitted (with or without scaling and filtering) with
vkCmdBlitImage
.
Multisampled images can be resolved to a non-multisampled image with
vkCmdResolveImage
.
19.1. Common Operation
The following valid usage rules apply to all copy commands:
-
Copy commands must be recorded outside of a render pass instance.
-
The set of all bytes bound to all the source regions must not overlap the set of all bytes bound to the destination regions.
-
The set of all bytes bound to each destination region must not overlap the set of all bytes bound to another destination region.
-
Copy regions must be non-empty.
-
Regions must not extend outside the bounds of the buffer or image level, except that regions of compressed images can extend as far as the dimension of the image level rounded up to a complete compressed texel block.
-
Source image subresources must be in either the
VK_IMAGE_LAYOUT_GENERAL
orVK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL
layout. Destination image subresources must be in theVK_IMAGE_LAYOUT_SHARED_PRESENT_KHR
,VK_IMAGE_LAYOUT_GENERAL
orVK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL
layout. As a consequence, if an image subresource is used as both source and destination of a copy, it must be in theVK_IMAGE_LAYOUT_GENERAL
layout. -
Source images must have
VK_FORMAT_FEATURE_TRANSFER_SRC_BIT
in their format features. -
Destination images must have
VK_FORMAT_FEATURE_TRANSFER_DST_BIT
in their format features. -
Source buffers must have been created with the
VK_BUFFER_USAGE_TRANSFER_SRC_BIT
usage bit enabled and destination buffers must have been created with theVK_BUFFER_USAGE_TRANSFER_DST_BIT
usage bit enabled. -
If the stencil aspect of source image is accessed, and the source image was not created with separate stencil usage, the source image must have been created with
VK_IMAGE_USAGE_TRANSFER_SRC_BIT
set in VkImageCreateInfo::usage
-
If the stencil aspect of destination image is accessed, and the destination image was not created with separate stencil usage, the destination image must have been created with
VK_IMAGE_USAGE_TRANSFER_DST_BIT
set in VkImageCreateInfo::usage
-
If the stencil aspect of source image is accessed, and the source image was created with separate stencil usage, the source image must have been created with
VK_IMAGE_USAGE_TRANSFER_SRC_BIT
set in VkImageStencilUsageCreateInfo::stencilUsage
-
If the stencil aspect of destination image is accessed, and the destination image was created with separate stencil usage, the destination image must have been created with
VK_IMAGE_USAGE_TRANSFER_DST_BIT
set in VkImageStencilUsageCreateInfo::stencilUsage
-
If non-stencil aspects of a source image are accessed, the source image must have been created with
VK_IMAGE_USAGE_TRANSFER_SRC_BIT
set in VkImageCreateInfo::usage
-
If non-stencil aspects of a source image are accessed, the source image must have been created with
VK_IMAGE_USAGE_TRANSFER_DST_BIT
set in VkImageCreateInfo::usage
All copy commands are treated as “transfer” operations for the purposes of synchronization barriers.
All copy commands that have a source format with an X component in its format description read undefined values from those bits.
All copy commands that have a destination format with an X component in its format description write undefined values to those bits.
19.2. Copying Data Between Buffers
To copy data between buffer objects, call:
// Provided by VK_VERSION_1_0
void vkCmdCopyBuffer(
VkCommandBuffer commandBuffer,
VkBuffer srcBuffer,
VkBuffer dstBuffer,
uint32_t regionCount,
const VkBufferCopy* pRegions);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcBuffer
is the source buffer. -
dstBuffer
is the destination buffer. -
regionCount
is the number of regions to copy. -
pRegions
is a pointer to an array of VkBufferCopy structures specifying the regions to copy.
Each region in pRegions
is copied from the source buffer to the same
region of the destination buffer.
srcBuffer
and dstBuffer
can be the same buffer or alias the
same memory, but the resulting values are undefined if the copy regions
overlap in memory.
The VkBufferCopy
structure is defined as:
// Provided by VK_VERSION_1_0
typedef struct VkBufferCopy {
VkDeviceSize srcOffset;
VkDeviceSize dstOffset;
VkDeviceSize size;
} VkBufferCopy;
-
srcOffset
is the starting offset in bytes from the start ofsrcBuffer
. -
dstOffset
is the starting offset in bytes from the start ofdstBuffer
. -
size
is the number of bytes to copy.
19.3. Copying Data Between Images
vkCmdCopyImage
performs image copies in a similar manner to a host
memcpy.
It does not perform general-purpose conversions such as scaling, resizing,
blending, color-space conversion, or format conversions.
Rather, it simply copies raw image data.
vkCmdCopyImage
can copy between images with different formats,
provided the formats are compatible as defined below.
To copy data between image objects, call:
// Provided by VK_VERSION_1_0
void vkCmdCopyImage(
VkCommandBuffer commandBuffer,
VkImage srcImage,
VkImageLayout srcImageLayout,
VkImage dstImage,
VkImageLayout dstImageLayout,
uint32_t regionCount,
const VkImageCopy* pRegions);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcImage
is the source image. -
srcImageLayout
is the current layout of the source image subresource. -
dstImage
is the destination image. -
dstImageLayout
is the current layout of the destination image subresource. -
regionCount
is the number of regions to copy. -
pRegions
is a pointer to an array of VkImageCopy structures specifying the regions to copy.
Each region in pRegions
is copied from the source image to the same
region of the destination image.
srcImage
and dstImage
can be the same image or alias the same
memory.
The formats of srcImage
and dstImage
must be compatible.
Formats are compatible if they share the same class, as shown in the
Compatible Formats table.
Depth/stencil formats must match exactly.
If the format of srcImage
or dstImage
is a
multi-planar image format,
regions of each plane to be copied must be specified separately using the
srcSubresource
and dstSubresource
members of the
VkImageCopy structure.
In this case, the aspectMask
of the srcSubresource
or
dstSubresource
that refers to the multi-planar image must be
VK_IMAGE_ASPECT_PLANE_0_BIT
, VK_IMAGE_ASPECT_PLANE_1_BIT
, or
VK_IMAGE_ASPECT_PLANE_2_BIT
.
For the purposes of vkCmdCopyImage
, each plane of a multi-planar image
is treated as having the format listed in Compatible formats of planes of multi-planar formats for
the plane identified by the aspectMask
of the corresponding
subresource.
This applies both to VkFormat and to coordinates used in the copy,
which correspond to texels in the plane rather than how these texels map
to coordinates in the image as a whole.
Note
For example, the |
vkCmdCopyImage
allows copying between size-compatible compressed and
uncompressed internal formats.
Formats are size-compatible if the texel block size of the uncompressed
format is equal to the texel block size of the compressed format.
Such a copy does not perform on-the-fly compression or decompression.
When copying from an uncompressed format to a compressed format, each texel
of uncompressed data of the source image is copied as a raw value to the
corresponding compressed texel block of the destination image.
When copying from a compressed format to an uncompressed format, each
compressed texel block of the source image is copied as a raw value to the
corresponding texel of uncompressed data in the destination image.
Thus, for example, it is legal to copy between a 128-bit uncompressed format
and a compressed format which has a 128-bit sized compressed texel block
representing 4×4 texels (using 8 bits per texel), or between a 64-bit
uncompressed format and a compressed format which has a 64-bit sized
compressed texel block representing 4×4 texels (using 4 bits per
texel).
When copying between compressed and uncompressed formats the extent
members represent the texel dimensions of the source image and not the
destination.
When copying from a compressed image to an uncompressed image the image
texel dimensions written to the uncompressed image will be source extent
divided by the compressed texel block dimensions.
When copying from an uncompressed image to a compressed image the image
texel dimensions written to the compressed image will be the source extent
multiplied by the compressed texel block dimensions.
In both cases the number of bytes read and the number of bytes written will
be identical.
Copying to or from block-compressed images is typically done in multiples of
the compressed texel block size.
For this reason the extent
must be a multiple of the compressed texel
block dimension.
There is one exception to this rule which is required to handle compressed
images created with dimensions that are not a multiple of the compressed
texel block dimensions: if the srcImage
is compressed, then:
-
If
extent.width
is not a multiple of the compressed texel block width, then (extent.width
+srcOffset.x
) must equal the image subresource width. -
If
extent.height
is not a multiple of the compressed texel block height, then (extent.height
+srcOffset.y
) must equal the image subresource height. -
If
extent.depth
is not a multiple of the compressed texel block depth, then (extent.depth
+srcOffset.z
) must equal the image subresource depth.
Similarly, if the dstImage
is compressed, then:
-
If
extent.width
is not a multiple of the compressed texel block width, then (extent.width
+dstOffset.x
) must equal the image subresource width. -
If
extent.height
is not a multiple of the compressed texel block height, then (extent.height
+dstOffset.y
) must equal the image subresource height. -
If
extent.depth
is not a multiple of the compressed texel block depth, then (extent.depth
+dstOffset.z
) must equal the image subresource depth.
This allows the last compressed texel block of the image in each non-multiple dimension to be included as a source or destination of the copy.
“_422
” image formats that are not
multi-planar are treated as
having a 2×1 compressed texel block for the purposes of these rules.
vkCmdCopyImage
can be used to copy image data between multisample
images, but both images must have the same number of samples.
The VkImageCopy
structure is defined as:
// Provided by VK_VERSION_1_0
typedef struct VkImageCopy {
VkImageSubresourceLayers srcSubresource;
VkOffset3D srcOffset;
VkImageSubresourceLayers dstSubresource;
VkOffset3D dstOffset;
VkExtent3D extent;
} VkImageCopy;
-
srcSubresource
anddstSubresource
are VkImageSubresourceLayers structures specifying the image subresources of the images used for the source and destination image data, respectively. -
srcOffset
anddstOffset
select the initialx
,y
, andz
offsets in texels of the sub-regions of the source and destination image data. -
extent
is the size in texels of the image to copy inwidth
,height
anddepth
.
For VK_IMAGE_TYPE_3D
images, copies are performed slice by slice
starting with the z
member of the srcOffset
or dstOffset
,
and copying depth
slices.
For images with multiple layers, copies are performed layer by layer
starting with the baseArrayLayer
member of the srcSubresource
or
dstSubresource
and copying layerCount
layers.
Image data can be copied between images with different image types.
If one image is VK_IMAGE_TYPE_3D
and the other image is
VK_IMAGE_TYPE_2D
with multiple layers, then each slice is copied to or
from a different layer.
Copies involving a multi-planar image format specify the region to be copied in terms of the
plane to be copied, not the coordinates of the multi-planar image.
This means that copies accessing the R/B planes of “_422
” format
images must fit the copied region within half the width
of the parent
image, and that copies accessing the R/B planes of “_420
” format
images must fit the copied region within half the width
and
height
of the parent image.
The VkImageSubresourceLayers
structure is defined as:
// Provided by VK_VERSION_1_0
typedef struct VkImageSubresourceLayers {
VkImageAspectFlags aspectMask;
uint32_t mipLevel;
uint32_t baseArrayLayer;
uint32_t layerCount;
} VkImageSubresourceLayers;
-
aspectMask
is a combination of VkImageAspectFlagBits, selecting the color, depth and/or stencil aspects to be copied. -
mipLevel
is the mipmap level to copy from. -
baseArrayLayer
andlayerCount
are the starting layer and number of layers to copy.
19.4. Copying Data Between Buffers and Images
To copy data from a buffer object to an image object, call:
// Provided by VK_VERSION_1_0
void vkCmdCopyBufferToImage(
VkCommandBuffer commandBuffer,
VkBuffer srcBuffer,
VkImage dstImage,
VkImageLayout dstImageLayout,
uint32_t regionCount,
const VkBufferImageCopy* pRegions);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcBuffer
is the source buffer. -
dstImage
is the destination image. -
dstImageLayout
is the layout of the destination image subresources for the copy. -
regionCount
is the number of regions to copy. -
pRegions
is a pointer to an array of VkBufferImageCopy structures specifying the regions to copy.
Each region in pRegions
is copied from the specified region of the
source buffer to the specified region of the destination image.
If the format of dstImage
is a
multi-planar image format,
regions of each plane to be a target of a copy must be specified separately
using the pRegions
member of the VkBufferImageCopy structure.
In this case, the aspectMask
of imageSubresource
must be
VK_IMAGE_ASPECT_PLANE_0_BIT
, VK_IMAGE_ASPECT_PLANE_1_BIT
, or
VK_IMAGE_ASPECT_PLANE_2_BIT
.
For the purposes of vkCmdCopyBufferToImage
, each plane of a
multi-planar image is treated as having the format listed in
Compatible formats of planes of multi-planar formats for the plane identified by the
aspectMask
of the corresponding subresource.
This applies both to VkFormat and to coordinates used in the copy,
which correspond to texels in the plane rather than how these texels map
to coordinates in the image as a whole.
To copy data from an image object to a buffer object, call:
// Provided by VK_VERSION_1_0
void vkCmdCopyImageToBuffer(
VkCommandBuffer commandBuffer,
VkImage srcImage,
VkImageLayout srcImageLayout,
VkBuffer dstBuffer,
uint32_t regionCount,
const VkBufferImageCopy* pRegions);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcImage
is the source image. -
srcImageLayout
is the layout of the source image subresources for the copy. -
dstBuffer
is the destination buffer. -
regionCount
is the number of regions to copy. -
pRegions
is a pointer to an array of VkBufferImageCopy structures specifying the regions to copy.
Each region in pRegions
is copied from the specified region of the
source image to the specified region of the destination buffer.
If the VkFormat of srcImage
is a
multi-planar image format,
regions of each plane to be a source of a copy must be specified separately
using the pRegions
member of the VkBufferImageCopy structure.
In this case, the aspectMask
of imageSubresource
must be
VK_IMAGE_ASPECT_PLANE_0_BIT
, VK_IMAGE_ASPECT_PLANE_1_BIT
, or
VK_IMAGE_ASPECT_PLANE_2_BIT
.
For the purposes of vkCmdCopyBufferToImage
, each plane of a
multi-planar image is treated as having the format listed in
Compatible formats of planes of multi-planar formats for the plane identified by the
aspectMask
of the corresponding subresource.
This applies both to VkFormat and to coordinates used in the copy,
which correspond to texels in the plane rather than how these texels map
to coordinates in the image as a whole.
For both vkCmdCopyBufferToImage and vkCmdCopyImageToBuffer, each
element of pRegions
is a structure defined as:
// Provided by VK_VERSION_1_0
typedef struct VkBufferImageCopy {
VkDeviceSize bufferOffset;
uint32_t bufferRowLength;
uint32_t bufferImageHeight;
VkImageSubresourceLayers imageSubresource;
VkOffset3D imageOffset;
VkExtent3D imageExtent;
} VkBufferImageCopy;
-
bufferOffset
is the offset in bytes from the start of the buffer object where the image data is copied from or to. -
bufferRowLength
andbufferImageHeight
specify in texels a subregion of a larger two- or three-dimensional image in buffer memory, and control the addressing calculations. If either of these values is zero, that aspect of the buffer memory is considered to be tightly packed according to theimageExtent
. -
imageSubresource
is a VkImageSubresourceLayers used to specify the specific image subresources of the image used for the source or destination image data. -
imageOffset
selects the initialx
,y
,z
offsets in texels of the sub-region of the source or destination image data. -
imageExtent
is the size in texels of the image to copy inwidth
,height
anddepth
.
When copying to or from a depth or stencil aspect, the data in buffer memory uses a layout that is a (mostly) tightly packed representation of the depth or stencil data. Specifically:
-
data copied to or from the stencil aspect of any depth/stencil format is tightly packed with one
VK_FORMAT_S8_UINT
value per texel. -
data copied to or from the depth aspect of a
VK_FORMAT_D16_UNORM
orVK_FORMAT_D16_UNORM_S8_UINT
format is tightly packed with oneVK_FORMAT_D16_UNORM
value per texel. -
data copied to or from the depth aspect of a
VK_FORMAT_D32_SFLOAT
orVK_FORMAT_D32_SFLOAT_S8_UINT
format is tightly packed with oneVK_FORMAT_D32_SFLOAT
value per texel. -
data copied to or from the depth aspect of a
VK_FORMAT_X8_D24_UNORM_PACK32
orVK_FORMAT_D24_UNORM_S8_UINT
format is packed with one 32-bit word per texel with the D24 value in the LSBs of the word, and undefined values in the eight MSBs.
Note
To copy both the depth and stencil aspects of a depth/stencil format, two
entries in |
Because depth or stencil aspect buffer to image copies may require format conversions on some implementations, they are not supported on queues that do not support graphics.
When copying to a depth aspect,
and the VK_EXT_depth_range_unrestricted
extension is not enabled,
the data in buffer memory must be in the range [0,1], or the
resulting values are undefined.
Copies are done layer by layer starting with image layer
baseArrayLayer
member of imageSubresource
.
layerCount
layers are copied from the source image or to the
destination image.
19.4.1. Buffer and Image Addressing
Pseudocode for image/buffer addressing of uncompressed formats is:
rowLength = region->bufferRowLength;
if (rowLength == 0)
rowLength = region->imageExtent.width;
imageHeight = region->bufferImageHeight;
if (imageHeight == 0)
imageHeight = region->imageExtent.height;
texelBlockSize = <texel block size of the format of the src/dstImage>;
address of (x,y,z) = region->bufferOffset + (((z * imageHeight) + y) * rowLength + x) * texelBlockSize;
where x,y,z range from (0,0,0) to region->imageExtent.{width,height,depth}.
Note that imageOffset
does not affect addressing calculations for
buffer memory.
Instead, bufferOffset
can be used to select the starting address in
buffer memory.
For block-compressed formats, all parameters are still specified in texels rather than compressed texel blocks, but the addressing math operates on whole compressed texel blocks. Pseudocode for compressed copy addressing is:
rowLength = region->bufferRowLength;
if (rowLength == 0)
rowLength = region->imageExtent.width;
imageHeight = region->bufferImageHeight;
if (imageHeight == 0)
imageHeight = region->imageExtent.height;
compressedTexelBlockSizeInBytes = <compressed texel block size taken from the src/dstImage>;
rowLength /= compressedTexelBlockWidth;
imageHeight /= compressedTexelBlockHeight;
address of (x,y,z) = region->bufferOffset + (((z * imageHeight) + y) * rowLength + x) * compressedTexelBlockSizeInBytes;
where x,y,z range from (0,0,0) to region->imageExtent.{width/compressedTexelBlockWidth,height/compressedTexelBlockHeight,depth/compressedTexelBlockDepth}.
Copying to or from block-compressed images is typically done in multiples of
the compressed texel block size.
For this reason the imageExtent
must be a multiple of the compressed
texel block dimension.
There is one exception to this rule which is required to handle compressed
images created with dimensions that are not a multiple of the compressed
texel block dimensions:
-
If
imageExtent.width
is not a multiple of the compressed texel block width, then (imageExtent.width
+imageOffset.x
) must equal the image subresource width. -
If
imageExtent.height
is not a multiple of the compressed texel block height, then (imageExtent.height
+imageOffset.y
) must equal the image subresource height. -
If
imageExtent.depth
is not a multiple of the compressed texel block depth, then (imageExtent.depth
+imageOffset.z
) must equal the image subresource depth.
This allows the last compressed texel block of the image in each non-multiple dimension to be included as a source or destination of the copy.
19.5. Image Copies with Scaling
To copy regions of a source image into a destination image, potentially performing format conversion, arbitrary scaling, and filtering, call:
// Provided by VK_VERSION_1_0
void vkCmdBlitImage(
VkCommandBuffer commandBuffer,
VkImage srcImage,
VkImageLayout srcImageLayout,
VkImage dstImage,
VkImageLayout dstImageLayout,
uint32_t regionCount,
const VkImageBlit* pRegions,
VkFilter filter);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcImage
is the source image. -
srcImageLayout
is the layout of the source image subresources for the blit. -
dstImage
is the destination image. -
dstImageLayout
is the layout of the destination image subresources for the blit. -
regionCount
is the number of regions to blit. -
pRegions
is a pointer to an array of VkImageBlit structures specifying the regions to blit. -
filter
is a VkFilter specifying the filter to apply if the blits require scaling.
vkCmdBlitImage
must not be used for multisampled source or
destination images.
Use vkCmdResolveImage for this purpose.
As the sizes of the source and destination extents can differ in any dimension, texels in the source extent are scaled and filtered to the destination extent. Scaling occurs via the following operations:
-
For each destination texel, the integer coordinate of that texel is converted to an unnormalized texture coordinate, using the effective inverse of the equations described in unnormalized to integer conversion:
-
ubase = i + ½
-
vbase = j + ½
-
wbase = k + ½
-
-
These base coordinates are then offset by the first destination offset:
-
uoffset = ubase - xdst0
-
voffset = vbase - ydst0
-
woffset = wbase - zdst0
-
aoffset = a -
baseArrayCount
dst
-
-
The scale is determined from the source and destination regions, and applied to the offset coordinates:
-
scaleu = (xsrc1 - xsrc0) / (xdst1 - xdst0)
-
scalev = (ysrc1 - ysrc0) / (ydst1 - ydst0)
-
scalew = (zsrc1 - zsrc0) / (zdst1 - zdst0)
-
uscaled = uoffset × scaleu
-
vscaled = voffset × scalev
-
wscaled = woffset × scalew
-
-
Finally the source offset is added to the scaled coordinates, to determine the final unnormalized coordinates used to sample from
srcImage
:-
u = uscaled + xsrc0
-
v = vscaled + ysrc0
-
w = wscaled + zsrc0
-
q =
mipLevel
-
a = aoffset +
baseArrayCount
src
-
These coordinates are used to sample from the source image, as described in
Image Operations chapter, with the filter mode equal to that
of filter
, a mipmap mode of VK_SAMPLER_MIPMAP_MODE_NEAREST
and
an address mode of VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE
.
Implementations must clamp at the edge of the source image, and may
additionally clamp to the edge of the source region.
Note
Due to allowable rounding errors in the generation of the source texture coordinates, it is not always possible to guarantee exactly which source texels will be sampled for a given blit. As rounding errors are implementation dependent, the exact results of a blitting operation are also implementation dependent. |
Blits are done layer by layer starting with the baseArrayLayer
member
of srcSubresource
for the source and dstSubresource
for the
destination.
layerCount
layers are blitted to the destination image.
When blitting 3D textures, slices in the destination region bounded by
dstOffsets
[0].z and dstOffsets
[1].z are sampled from slices in
the source region bounded by srcOffsets
[0].z and
srcOffsets
[1].z.
If the filter
parameter is VK_FILTER_LINEAR
then the value
sampled from the source image is taken by doing linear filtering using the
interpolated z coordinate represented by w in the previous equations.
If the filter
parameter is VK_FILTER_NEAREST
then the value
sampled from the source image is taken from the single nearest slice, with
an implementation-dependent arithmetic rounding mode.
The following filtering and conversion rules apply:
-
Integer formats can only be converted to other integer formats with the same signedness.
-
No format conversion is supported between depth/stencil images. The formats must match.
-
Format conversions on unorm, snorm, unscaled and packed float formats of the copied aspect of the image are performed by first converting the pixels to float values.
-
For sRGB source formats, nonlinear RGB values are converted to linear representation prior to filtering.
-
After filtering, the float values are first clamped and then cast to the destination image format. In case of sRGB destination format, linear RGB values are converted to nonlinear representation before writing the pixel to the image.
Signed and unsigned integers are converted by first clamping to the representable range of the destination format, then casting the value.
The VkImageBlit
structure is defined as:
// Provided by VK_VERSION_1_0
typedef struct VkImageBlit {
VkImageSubresourceLayers srcSubresource;
VkOffset3D srcOffsets[2];
VkImageSubresourceLayers dstSubresource;
VkOffset3D dstOffsets[2];
} VkImageBlit;
-
srcSubresource
is the subresource to blit from. -
srcOffsets
is a pointer to an array of two VkOffset3D structures specifying the bounds of the source region withinsrcSubresource
. -
dstSubresource
is the subresource to blit into. -
dstOffsets
is a pointer to an array of two VkOffset3D structures specifying the bounds of the destination region withindstSubresource
.
For each element of the pRegions
array, a blit operation is performed
the specified source and destination regions.
19.6. Resolving Multisample Images
To resolve a multisample image to a non-multisample image, call:
// Provided by VK_VERSION_1_0
void vkCmdResolveImage(
VkCommandBuffer commandBuffer,
VkImage srcImage,
VkImageLayout srcImageLayout,
VkImage dstImage,
VkImageLayout dstImageLayout,
uint32_t regionCount,
const VkImageResolve* pRegions);
-
commandBuffer
is the command buffer into which the command will be recorded. -
srcImage
is the source image. -
srcImageLayout
is the layout of the source image subresources for the resolve. -
dstImage
is the destination image. -
dstImageLayout
is the layout of the destination image subresources for the resolve. -
regionCount
is the number of regions to resolve. -
pRegions
is a pointer to an array of VkImageResolve structures specifying the regions to resolve.
During the resolve the samples corresponding to each pixel location in the source are converted to a single sample before being written to the destination. If the source formats are floating-point or normalized types, the sample values for each pixel are resolved in an implementation-dependent manner. If the source formats are integer types, a single sample’s value is selected for each pixel.
srcOffset
and dstOffset
select the initial x
, y
, and
z
offsets in texels of the sub-regions of the source and destination
image data.
extent
is the size in texels of the source image to resolve in
width
, height
and depth
.
Each element of pRegions
must be a region that is contained within
its corresponding image.
Resolves are done layer by layer starting with baseArrayLayer
member
of srcSubresource
for the source and dstSubresource
for the
destination.
layerCount
layers are resolved to the destination image.
The VkImageResolve
structure is defined as:
// Provided by VK_VERSION_1_0
typedef struct VkImageResolve {
VkImageSubresourceLayers srcSubresource;
VkOffset3D srcOffset;
VkImageSubresourceLayers dstSubresource;
VkOffset3D dstOffset;
VkExtent3D extent;
} VkImageResolve;
-
srcSubresource
anddstSubresource
are VkImageSubresourceLayers structures specifying the image subresources of the images used for the source and destination image data, respectively. Resolve of depth/stencil images is not supported. -
srcOffset
anddstOffset
select the initialx
,y
, andz
offsets in texels of the sub-regions of the source and destination image data. -
extent
is the size in texels of the source image to resolve inwidth
,height
anddepth
.
19.7. Buffer Markers
To write a 32-bit marker value into a buffer as a pipelined operation, call:
// Provided by VK_AMD_buffer_marker
void vkCmdWriteBufferMarkerAMD(
VkCommandBuffer commandBuffer,
VkPipelineStageFlagBits pipelineStage,
VkBuffer dstBuffer,
VkDeviceSize dstOffset,
uint32_t marker);
-
commandBuffer
is the command buffer into which the command will be recorded. -
pipelineStage
is one of the VkPipelineStageFlagBits values, specifying the pipeline stage whose completion triggers the marker write. -
dstBuffer
is the buffer where the marker will be written to. -
dstOffset
is the byte offset into the buffer where the marker will be written to. -
marker
is the 32-bit value of the marker.
The command will write the 32-bit marker value into the buffer only after
all preceding commands have finished executing up to at least the specified
pipeline stage.
This includes the completion of other preceding
vkCmdWriteBufferMarkerAMD
commands so long as their specified pipeline
stages occur either at the same time or earlier than this command’s
specified pipelineStage
.
While consecutive buffer marker writes with the same pipelineStage
parameter are implicitly complete in submission order, memory and execution
dependencies between buffer marker writes and other operations must still be
explicitly ordered using synchronization commands.
The access scope for buffer marker writes falls under the
VK_ACCESS_TRANSFER_WRITE_BIT
, and the pipeline stages for identifying
the synchronization scope must include both pipelineStage
and
VK_PIPELINE_STAGE_TRANSFER_BIT
.
Note
Similar to |
Note
Implementations may only support a limited number of pipelined marker write operations in flight at a given time, thus excessive number of marker write operations may degrade command execution performance. |