Vulkan-Docs/doc/specs/vulkan/man/vkCmdCopyImage.txt

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// Copyright (c) 2014-2016 Khronos Group. This work is licensed under a
// Creative Commons Attribution 4.0 International License; see
// http://creativecommons.org/licenses/by/4.0/
vkCmdCopyImage(3)
=================
Name
----
vkCmdCopyImage - Copy data between images.
C Specification
---------------
// refBegin vkCmdCopyImage Copy data between images.
To copy data between image objects, call:
include::../protos/vkCmdCopyImage.txt[]
Parameters
----------
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:srcImage is the source image.
* pname:srcImageLayout is the current layout of the source image
subresource.
* pname:dstImage is the destination image.
* pname:dstImageLayout is the current layout of the destination image
subresource.
* pname:regionCount is the number of regions to copy.
* pname:pRegions is a pointer to an array of slink:VkImageCopy structures
specifying the regions to copy.
Description
-----------
Each region in pname:pRegions is copied from the source image to the same
region of the destination image. pname:srcImage and pname:dstImage can: be
the same image or alias the same memory.
Copies are done layer by layer starting with pname:baseArrayLayer member of
pname:srcSubresource for the source and pname:dstSubresource for the
destination. pname:layerCount layers are copied to the destination image.
[[copies-images-format-compatibility]]
The formats of pname:srcImage and pname:dstImage must: be compatible.
Formats are considered compatible if their texel size in bytes is the same
between both formats. For example, ename:VK_FORMAT_R8G8B8A8_UNORM is
compatible with ename:VK_FORMAT_R32_UINT because both texels are 4
bytes in size. Depth/stencil formats must: match exactly.
fname:vkCmdCopyImage allows copying between size-compatible compressed
and uncompressed internal formats. Formats are size-compatible if the texel
size of the uncompressed format is equal to the compressed texel block size in
bytes 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 4x4 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 4x4 texels (using 4 bits per texel).
When copying between compressed and uncompressed formats the pname: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. For this reason the pname: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 pname:srcImage is compressed and if pname:extent.width is not a
multiple of the compressed texel block width then (pname:extent.width +
pname:srcOffset.x) must: equal the image subresource width, if
pname:extent.height is not a multiple of the compressed texel block height
then (pname:extent.height + pname:srcOffset.y) must: equal the image
subresource height and if pname:extent.depth is not a multiple of the
compressed texel block depth then (pname:extent.depth + pname:srcOffset.z)
must: equal the image subresource depth. Similarly, if the pname:dstImage is
compressed and if pname:extent.width is not a multiple of the compressed
texel block width then (pname:extent.width + pname:dstOffset.x) must: equal
the image subresource width, if pname:extent.height is not a multiple of the
compressed texel block height then (pname:extent.height + pname:dstOffset.y)
must: equal the image subresource height and if pname:extent.depth is not a
multiple of the compressed texel block depth then (pname:extent.depth +
pname: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.
fname:vkCmdCopyImage can: be used to copy image data between multisample
images, but both images must: have the same number of samples.
include::../validity/protos/vkCmdCopyImage.txt[]
See Also
--------
slink:VkCommandBuffer, slink:VkImage, slink:VkImageCopy, elink:VkImageLayout
Document Notes
--------------
For more information, see the Vulkan Specification at URL
https://www.khronos.org/registry/vulkan/specs/1.0/xhtml/vkspec.html#vkCmdCopyImage
This page is extracted from the Vulkan Specification.
Fixes and changes should be made to the Specification,not directly.
include::footer.txt[]