Vulkan-Docs/chapters/clears.txt

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// Copyright (c) 2015-2019 Khronos Group. This work is licensed under a
// Creative Commons Attribution 4.0 International License; see
// http://creativecommons.org/licenses/by/4.0/
[[clears]]
= Clear Commands
[[clears-outside]]
== Clearing Images Outside A Render Pass Instance
Color and depth/stencil images can: be cleared outside a render pass
instance using flink:vkCmdClearColorImage or
flink:vkCmdClearDepthStencilImage, respectively.
These commands are only allowed outside of a render pass instance.
[open,refpage='vkCmdClearColorImage',desc='Clear regions of a color image',type='protos']
--
To clear one or more subranges of a color image, call:
include::../api/protos/vkCmdClearColorImage.txt[]
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:image is the image to be cleared.
* pname:imageLayout specifies the current layout of the image subresource
ranges to be cleared, and must: be
ifdef::VK_KHR_shared_presentable_image[]
ename:VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR,
endif::VK_KHR_shared_presentable_image[]
ename:VK_IMAGE_LAYOUT_GENERAL or
ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL.
* pname:pColor is a pointer to a slink:VkClearColorValue structure that
contains the values the image subresource ranges will be cleared to (see
<<clears-values>> below).
* pname:rangeCount is the number of image subresource range structures in
pname:pRanges.
* pname:pRanges points to an array of slink:VkImageSubresourceRange
structures that describe a range of mipmap levels, array layers, and
aspects to be cleared, as described in <<resources-image-views,Image
Views>>.
Each specified range in pname:pRanges is cleared to the value specified by
pname:pColor.
.Valid Usage
****
ifdef::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdClearColorImage-image-01993]]
The <<resources-image-format-features,format features>> of pname:image
must: contain ename:VK_FORMAT_FEATURE_TRANSFER_DST_BIT.
endif::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdClearColorImage-image-00002]]
pname:image must: have been created with
ename:VK_IMAGE_USAGE_TRANSFER_DST_BIT usage flag
ifdef::VK_VERSION_1_1,VK_KHR_sampler_ycbcr_conversion[]
* [[VUID-vkCmdClearColorImage-image-01545]]
pname:image must: not use a format listed in
<<features-formats-requiring-sampler-ycbcr-conversion>>
endif::VK_VERSION_1_1,VK_KHR_sampler_ycbcr_conversion[]
* [[VUID-vkCmdClearColorImage-image-00003]]
If pname:image is non-sparse then it must: be bound completely and
contiguously to a single sname:VkDeviceMemory object
* [[VUID-vkCmdClearColorImage-imageLayout-00004]]
pname:imageLayout must: specify the layout of the image subresource
ranges of pname:image specified in pname:pRanges at the time this
command is executed on a sname:VkDevice
ifndef::VK_KHR_shared_presentable_image[]
* [[VUID-vkCmdClearColorImage-imageLayout-00005]]
pname:imageLayout must: be ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL or
ename:VK_IMAGE_LAYOUT_GENERAL
endif::VK_KHR_shared_presentable_image[]
ifdef::VK_KHR_shared_presentable_image[]
* [[VUID-vkCmdClearColorImage-imageLayout-01394]]
pname:imageLayout must: be ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
ename:VK_IMAGE_LAYOUT_GENERAL, or
ename:VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR
endif::VK_KHR_shared_presentable_image[]
* [[VUID-vkCmdClearColorImage-aspectMask-02498]]
The slink:VkImageSubresourceRange::pname:aspectMask members of the
elements of the pname:pRanges array must: each only include
ename:VK_IMAGE_ASPECT_COLOR_BIT
* [[VUID-vkCmdClearColorImage-baseMipLevel-01470]]
The slink:VkImageSubresourceRange::pname:baseMipLevel members of the
elements of the pname:pRanges array must: each be less than the
pname:mipLevels specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearColorImage-pRanges-01692]]
For each slink:VkImageSubresourceRange element of pname:pRanges, if the
pname:levelCount member is not ename:VK_REMAINING_MIP_LEVELS, then
[eq]#pname:baseMipLevel {plus} pname:levelCount# must: be less than the
pname:mipLevels specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearColorImage-baseArrayLayer-01472]]
The slink:VkImageSubresourceRange::pname:baseArrayLayer members of the
elements of the pname:pRanges array must: each be less than the
pname:arrayLayers specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearColorImage-pRanges-01693]]
For each slink:VkImageSubresourceRange element of pname:pRanges, if the
pname:layerCount member is not ename:VK_REMAINING_ARRAY_LAYERS, then
[eq]#pname:baseArrayLayer {plus} pname:layerCount# must: be less than
the pname:arrayLayers specified in slink:VkImageCreateInfo when
pname:image was created
* [[VUID-vkCmdClearColorImage-image-00007]]
pname:image must: not have a compressed or depth/stencil format
ifdef::VK_VERSION_1_1[]
* [[VUID-vkCmdClearColorImage-commandBuffer-01805]]
If pname:commandBuffer is an unprotected command buffer, then
pname:image must: not be a protected image
* [[VUID-vkCmdClearColorImage-commandBuffer-01806]]
If pname:commandBuffer is a protected command buffer, then pname:image
must: not be an unprotected image
endif::VK_VERSION_1_1[]
****
include::../validity/protos/vkCmdClearColorImage.txt[]
--
[open,refpage='vkCmdClearDepthStencilImage',desc='Fill regions of a combined depth/stencil image',type='protos']
--
To clear one or more subranges of a depth/stencil image, call:
include::../api/protos/vkCmdClearDepthStencilImage.txt[]
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:image is the image to be cleared.
* pname:imageLayout specifies the current layout of the image subresource
ranges to be cleared, and must: be ename:VK_IMAGE_LAYOUT_GENERAL or
ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL.
* pname:pDepthStencil is a pointer to a slink:VkClearDepthStencilValue
structure that contains the values the depth and stencil image
subresource ranges will be cleared to (see <<clears-values>> below).
* pname:rangeCount is the number of image subresource range structures in
pname:pRanges.
* pname:pRanges points to an array of slink:VkImageSubresourceRange
structures that describe a range of mipmap levels, array layers, and
aspects to be cleared, as described in <<resources-image-views,Image
Views>>.
.Valid Usage
****
ifdef::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdClearDepthStencilImage-image-01994]]
The <<resources-image-format-features,format features>> of pname:image
must: contain ename:VK_FORMAT_FEATURE_TRANSFER_DST_BIT.
endif::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdClearDepthStencilImage-image-00009]]
pname:image must: have been created with
ename:VK_IMAGE_USAGE_TRANSFER_DST_BIT usage flag
* [[VUID-vkCmdClearDepthStencilImage-image-00010]]
If pname:image is non-sparse then it must: be bound completely and
contiguously to a single sname:VkDeviceMemory object
* [[VUID-vkCmdClearDepthStencilImage-imageLayout-00011]]
pname:imageLayout must: specify the layout of the image subresource
ranges of pname:image specified in pname:pRanges at the time this
command is executed on a sname:VkDevice
* [[VUID-vkCmdClearDepthStencilImage-imageLayout-00012]]
pname:imageLayout must: be either of
ename:VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL or
ename:VK_IMAGE_LAYOUT_GENERAL
* [[VUID-vkCmdClearDepthStencilImage-aspectMask-02499]]
The slink:VkImageSubresourceRange::pname:aspectMask members of the
elements of the pname:pRanges array must: each only include
ename:VK_IMAGE_ASPECT_DEPTH_BIT if the image format has a depth
component
* [[VUID-vkCmdClearDepthStencilImage-aspectMask-02500]]
The slink:VkImageSubresourceRange::pname:aspectMask members of the
elements of the pname:pRanges array must: each only include
ename:VK_IMAGE_ASPECT_STENCIL_BIT if the image format has a stencil
component
* [[VUID-vkCmdClearDepthStencilImage-baseMipLevel-01474]]
The slink:VkImageSubresourceRange::pname:baseMipLevel members of the
elements of the pname:pRanges array must: each be less than the
pname:mipLevels specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearDepthStencilImage-pRanges-01694]]
For each slink:VkImageSubresourceRange element of pname:pRanges, if the
pname:levelCount member is not ename:VK_REMAINING_MIP_LEVELS, then
[eq]#pname:baseMipLevel {plus} pname:levelCount# must: be less than the
pname:mipLevels specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearDepthStencilImage-baseArrayLayer-01476]]
The slink:VkImageSubresourceRange::pname:baseArrayLayer members of the
elements of the pname:pRanges array must: each be less than the
pname:arrayLayers specified in slink:VkImageCreateInfo when pname:image
was created
* [[VUID-vkCmdClearDepthStencilImage-pRanges-01695]]
For each slink:VkImageSubresourceRange element of pname:pRanges, if the
pname:layerCount member is not ename:VK_REMAINING_ARRAY_LAYERS, then
[eq]#pname:baseArrayLayer {plus} pname:layerCount# must: be less than
the pname:arrayLayers specified in slink:VkImageCreateInfo when
pname:image was created
* [[VUID-vkCmdClearDepthStencilImage-image-00014]]
pname:image must: have a depth/stencil format
ifdef::VK_VERSION_1_1[]
* [[VUID-vkCmdClearDepthStencilImage-commandBuffer-01807]]
If pname:commandBuffer is an unprotected command buffer, then
pname:image must: not be a protected image
* [[VUID-vkCmdClearDepthStencilImage-commandBuffer-01808]]
If pname:commandBuffer is a protected command buffer, then pname:image
must: not be an unprotected image
endif::VK_VERSION_1_1[]
****
include::../validity/protos/vkCmdClearDepthStencilImage.txt[]
--
Clears outside render pass instances are treated as transfer operations for
the purposes of memory barriers.
[[clears-inside]]
== Clearing Images Inside A Render Pass Instance
[open,refpage='vkCmdClearAttachments',desc='Clear regions within bound framebuffer attachments',type='protos']
--
To clear one or more regions of color and depth/stencil attachments inside a
render pass instance, call:
include::../api/protos/vkCmdClearAttachments.txt[]
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:attachmentCount is the number of entries in the pname:pAttachments
array.
* pname:pAttachments is a pointer to an array of slink:VkClearAttachment
structures defining the attachments to clear and the clear values to
use.
If any attachment to be cleared in the current subpass is
ename:VK_ATTACHMENT_UNUSED, then the clear has no effect on that
attachment.
* pname:rectCount is the number of entries in the pname:pRects array.
* pname:pRects points to an array of slink:VkClearRect structures defining
regions within each selected attachment to clear.
fname:vkCmdClearAttachments can: clear multiple regions of each attachment
used in the current subpass of a render pass instance.
This command must: be called only inside a render pass instance, and
implicitly selects the images to clear based on the current framebuffer
attachments and the command parameters.
ifdef::VK_EXT_fragment_density_map[]
If the render pass has a <<renderpass-fragmentdensitymapattachment,fragment
density map attachment>>, clears follow the
<<fragmentdensitymapops,operations of fragment density maps>> as if each
clear region was a primitive which generates fragments.
The clear color is applied to all pixels inside each fragment's area
regardless if the pixels lie outside of the clear region.
Clears may: have a different set of supported fragment areas than draws.
endif::VK_EXT_fragment_density_map[]
Unlike other <<clears,clear commands>>, flink:vkCmdClearAttachments executes
as a drawing command, rather than a transfer command, with writes performed
by it executing in <<primrast-order, rasterization order>>.
Clears to color attachments are executed as color attachment writes, by the
ename:VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT stage.
Clears to depth/stencil attachments are executed as <<fragops-depth, depth
writes>> and <<fragops-stencil, writes>> by the
ename:VK_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT and
ename:VK_PIPELINE_STAGE_LATE_FRAGMENT_TESTS_BIT stages.
.Valid Usage
****
* [[VUID-vkCmdClearAttachments-aspectMask-02501]]
If the pname:aspectMask member of any element of pname:pAttachments
contains ename:VK_IMAGE_ASPECT_COLOR_BIT, then the pname:colorAttachment
member of that element must: either refer to a color attachment which is
ename:VK_ATTACHMENT_UNUSED, or must: be a valid color attachment.
* [[VUID-vkCmdClearAttachments-aspectMask-02502]]
If the pname:aspectMask member of any element of pname:pAttachments
contains ename:VK_IMAGE_ASPECT_DEPTH_BIT, then the current subpass'
depth/stencil attachment must: either be ename:VK_ATTACHMENT_UNUSED, or
must: have a depth component
* [[VUID-vkCmdClearAttachments-aspectMask-02503]]
If the pname:aspectMask member of any element of pname:pAttachments
contains ename:VK_IMAGE_ASPECT_STENCIL_BIT, then the current subpass'
depth/stencil attachment must: either be ename:VK_ATTACHMENT_UNUSED, or
must: have a stencil component
* [[VUID-vkCmdClearAttachments-pRects-00016]]
The rectangular region specified by each element of pname:pRects must:
be contained within the render area of the current render pass instance
* [[VUID-vkCmdClearAttachments-pRects-00017]]
The layers specified by each element of pname:pRects must: be contained
within every attachment that pname:pAttachments refers to
* [[VUID-vkCmdClearAttachments-layerCount-01934]]
The pname:layerCount member of each element of pname:pRects must: not be
`0`
ifdef::VK_VERSION_1_1[]
* [[VUID-vkCmdClearAttachments-commandBuffer-02504]]
If pname:commandBuffer is an unprotected command buffer, then each
attachment to be cleared must: not be a protected image.
* [[VUID-vkCmdClearAttachments-commandBuffer-02505]]
If pname:commandBuffer is a protected command buffer, then each
attachment to be cleared must: not be an unprotected image.
endif::VK_VERSION_1_1[]
ifdef::VK_VERSION_1_1,VK_KHR_multiview[]
* [[VUID-vkCmdClearAttachments-baseArrayLayer-00018]]
If the render pass instance this is recorded in uses multiview, then
pname:baseArrayLayer must: be zero and pname:layerCount must: be one.
endif::VK_VERSION_1_1,VK_KHR_multiview[]
****
include::../validity/protos/vkCmdClearAttachments.txt[]
--
[open,refpage='VkClearRect',desc='Structure specifying a clear rectangle',type='structs']
--
The sname:VkClearRect structure is defined as:
include::../api/structs/VkClearRect.txt[]
* pname:rect is the two-dimensional region to be cleared.
* pname:baseArrayLayer is the first layer to be cleared.
* pname:layerCount is the number of layers to clear.
The layers [eq]#[pname:baseArrayLayer, pname:baseArrayLayer {plus}
pname:layerCount)# counting from the base layer of the attachment image view
are cleared.
include::../validity/structs/VkClearRect.txt[]
--
[open,refpage='VkClearAttachment',desc='Structure specifying a clear attachment',type='structs']
--
The sname:VkClearAttachment structure is defined as:
include::../api/structs/VkClearAttachment.txt[]
* pname:aspectMask is a mask selecting the color, depth and/or stencil
aspects of the attachment to be cleared.
* pname:colorAttachment is only meaningful if
ename:VK_IMAGE_ASPECT_COLOR_BIT is set in pname:aspectMask, in which
case it is an index to the pname:pColorAttachments array in the
slink:VkSubpassDescription structure of the current subpass which
selects the color attachment to clear.
* pname:clearValue is the color or depth/stencil value to clear the
attachment to, as described in <<clears-values,Clear Values>> below.
No memory barriers are needed between fname:vkCmdClearAttachments and
preceding or subsequent draw or attachment clear commands in the same
subpass.
The fname:vkCmdClearAttachments command is not affected by the bound
pipeline state.
Attachments can: also be cleared at the beginning of a render pass instance
by setting pname:loadOp (or pname:stencilLoadOp) of
slink:VkAttachmentDescription to ename:VK_ATTACHMENT_LOAD_OP_CLEAR, as
described for flink:vkCreateRenderPass.
.Valid Usage
****
* [[VUID-VkClearAttachment-aspectMask-00019]]
If pname:aspectMask includes ename:VK_IMAGE_ASPECT_COLOR_BIT, it must:
not include ename:VK_IMAGE_ASPECT_DEPTH_BIT or
ename:VK_IMAGE_ASPECT_STENCIL_BIT
* [[VUID-VkClearAttachment-aspectMask-00020]]
pname:aspectMask must: not include ename:VK_IMAGE_ASPECT_METADATA_BIT
ifdef::VK_EXT_image_drm_format_modifier[]
* [[VUID-VkClearAttachment-aspectMask-02246]]
pname:aspectMask must: not include
etext:VK_IMAGE_ASPECT_MEMORY_PLANE___i___BIT_EXT for any index __i__.
endif::VK_EXT_image_drm_format_modifier[]
* [[VUID-VkClearAttachment-clearValue-00021]]
pname:clearValue must: be a valid sname:VkClearValue union
****
include::../validity/structs/VkClearAttachment.txt[]
--
[[clears-values]]
== Clear Values
[open,refpage='VkClearColorValue',desc='Structure specifying a clear color value',type='structs']
--
The sname:VkClearColorValue structure is defined as:
include::../api/structs/VkClearColorValue.txt[]
* pname:float32 are the color clear values when the format of the image or
attachment is one of the formats in the
<<features-formats-numericformat, Interpretation of Numeric Format>>
table other than signed integer (etext:SINT) or unsigned integer
(etext:UINT).
Floating point values are automatically converted to the format of the
image, with the clear value being treated as linear if the image is
sRGB.
* pname:int32 are the color clear values when the format of the image or
attachment is signed integer (etext:SINT).
Signed integer values are converted to the format of the image by
casting to the smaller type (with negative 32-bit values mapping to
negative values in the smaller type).
If the integer clear value is not representable in the target type (e.g.
would overflow in conversion to that type), the clear value is
undefined:.
* pname:uint32 are the color clear values when the format of the image or
attachment is unsigned integer (etext:UINT).
Unsigned integer values are converted to the format of the image by
casting to the integer type with fewer bits.
The four array elements of the clear color map to R, G, B, and A components
of image formats, in order.
If the image has more than one sample, the same value is written to all
samples for any pixels being cleared.
include::../validity/structs/VkClearColorValue.txt[]
--
[open,refpage='VkClearDepthStencilValue',desc='Structure specifying a clear depth stencil value',type='structs']
--
The sname:VkClearDepthStencilValue structure is defined as:
include::../api/structs/VkClearDepthStencilValue.txt[]
* pname:depth is the clear value for the depth aspect of the depth/stencil
attachment.
It is a floating-point value which is automatically converted to the
attachment's format.
* pname:stencil is the clear value for the stencil aspect of the
depth/stencil attachment.
It is a 32-bit integer value which is converted to the attachment's
format by taking the appropriate number of LSBs.
.Valid Usage
****
ifdef::VK_EXT_depth_range_unrestricted[]
* [[VUID-VkClearDepthStencilValue-depth-00022]]
Unless the `<<VK_EXT_depth_range_unrestricted>>` extension is enabled
pname:depth must: be between `0.0` and `1.0`, inclusive
endif::VK_EXT_depth_range_unrestricted[]
ifndef::VK_EXT_depth_range_unrestricted[]
* [[VUID-VkClearDepthStencilValue-depth-02506]]
pname:depth must: be between `0.0` and `1.0`, inclusive
endif::VK_EXT_depth_range_unrestricted[]
****
include::../validity/structs/VkClearDepthStencilValue.txt[]
--
[open,refpage='VkClearValue',desc='Structure specifying a clear value',type='structs']
--
The sname:VkClearValue union is defined as:
include::../api/structs/VkClearValue.txt[]
* pname:color specifies the color image clear values to use when clearing
a color image or attachment.
* pname:depthStencil specifies the depth and stencil clear values to use
when clearing a depth/stencil image or attachment.
This union is used where part of the API requires either color or
depth/stencil clear values, depending on the attachment, and defines the
initial clear values in the slink:VkRenderPassBeginInfo structure.
include::../validity/structs/VkClearValue.txt[]
--
[[clears-filling-buffers]]
== Filling Buffers
[open,refpage='vkCmdFillBuffer',desc='Fill a region of a buffer with a fixed value',type='protos']
--
To clear buffer data, call:
include::../api/protos/vkCmdFillBuffer.txt[]
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:dstBuffer is the buffer to be filled.
* pname:dstOffset is the byte offset into the buffer at which to start
filling, and must: be a multiple of 4.
* pname:size is the number of bytes to fill, and must: be either a
multiple of 4, or ename:VK_WHOLE_SIZE to fill the range from
pname:offset to the end of the buffer.
If ename:VK_WHOLE_SIZE is used and the remaining size of the buffer is
not a multiple of 4, then the nearest smaller multiple is used.
* pname:data is the 4-byte word written repeatedly to the buffer to fill
pname:size bytes of data.
The data word is written to memory according to the host endianness.
fname:vkCmdFillBuffer is treated as "`transfer`" operation for the purposes
of synchronization barriers.
The ename:VK_BUFFER_USAGE_TRANSFER_DST_BIT must: be specified in pname:usage
of sname:VkBufferCreateInfo in order for the buffer to be compatible with
fname:vkCmdFillBuffer.
.Valid Usage
****
* [[VUID-vkCmdFillBuffer-dstOffset-00024]]
pname:dstOffset must: be less than the size of pname:dstBuffer
* [[VUID-vkCmdFillBuffer-dstOffset-00025]]
pname:dstOffset must: be a multiple of `4`
* [[VUID-vkCmdFillBuffer-size-00026]]
If pname:size is not equal to ename:VK_WHOLE_SIZE, pname:size must: be
greater than `0`
* [[VUID-vkCmdFillBuffer-size-00027]]
If pname:size is not equal to ename:VK_WHOLE_SIZE, pname:size must: be
less than or equal to the size of pname:dstBuffer minus pname:dstOffset
* [[VUID-vkCmdFillBuffer-size-00028]]
If pname:size is not equal to ename:VK_WHOLE_SIZE, pname:size must: be a
multiple of `4`
* [[VUID-vkCmdFillBuffer-dstBuffer-00029]]
pname:dstBuffer must: have been created with
ename:VK_BUFFER_USAGE_TRANSFER_DST_BIT usage flag
ifndef::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdFillBuffer-commandBuffer-00030]]
The sname:VkCommandPool that pname:commandBuffer was allocated from
must: support graphics or compute operations
endif::VK_VERSION_1_1,VK_KHR_maintenance1[]
* [[VUID-vkCmdFillBuffer-dstBuffer-00031]]
If pname:dstBuffer is non-sparse then it must: be bound completely and
contiguously to a single sname:VkDeviceMemory object
ifdef::VK_VERSION_1_1[]
* [[VUID-vkCmdFillBuffer-commandBuffer-01811]]
If pname:commandBuffer is an unprotected command buffer, then
pname:dstBuffer must: not be a protected buffer
* [[VUID-vkCmdFillBuffer-commandBuffer-01812]]
If pname:commandBuffer is a protected command buffer, then
pname:dstBuffer must: not be an unprotected buffer
endif::VK_VERSION_1_1[]
****
include::../validity/protos/vkCmdFillBuffer.txt[]
--
[[clears-updating-buffers]]
== Updating Buffers
[open,refpage='vkCmdUpdateBuffer',desc='Update a buffer\'s contents from host memory',type='protos']
--
To update buffer data inline in a command buffer, call:
include::../api/protos/vkCmdUpdateBuffer.txt[]
* pname:commandBuffer is the command buffer into which the command will be
recorded.
* pname:dstBuffer is a handle to the buffer to be updated.
* pname:dstOffset is the byte offset into the buffer to start updating,
and must: be a multiple of 4.
* pname:dataSize is the number of bytes to update, and must: be a multiple
of 4.
* pname:pData is a pointer to the source data for the buffer update, and
must: be at least pname:dataSize bytes in size.
pname:dataSize must: be less than or equal to 65536 bytes.
For larger updates, applications can: use buffer to buffer
<<copies-buffers,copies>>.
[NOTE]
.Note
====
Buffer updates performed with fname:vkCmdUpdateBuffer first copy the data
into command buffer memory when the command is recorded (which requires
additional storage and may incur an additional allocation), and then copy
the data from the command buffer into pname:dstBuffer when the command is
executed on a device.
The additional cost of this functionality compared to <<copies-buffers,
buffer to buffer copies>> means it is only recommended for very small
amounts of data, and is why it is limited to only 65536 bytes.
Applications can: work around this by issuing multiple
fname:vkCmdUpdateBuffer commands to different ranges of the same buffer, but
it is strongly recommended that they should: not.
====
The source data is copied from the user pointer to the command buffer when
the command is called.
fname:vkCmdUpdateBuffer is only allowed outside of a render pass.
This command is treated as "`transfer`" operation, for the purposes of
synchronization barriers.
The ename:VK_BUFFER_USAGE_TRANSFER_DST_BIT must: be specified in pname:usage
of slink:VkBufferCreateInfo in order for the buffer to be compatible with
fname:vkCmdUpdateBuffer.
.Valid Usage
****
* [[VUID-vkCmdUpdateBuffer-dstOffset-00032]]
pname:dstOffset must: be less than the size of pname:dstBuffer
* [[VUID-vkCmdUpdateBuffer-dataSize-00033]]
pname:dataSize must: be less than or equal to the size of
pname:dstBuffer minus pname:dstOffset
* [[VUID-vkCmdUpdateBuffer-dstBuffer-00034]]
pname:dstBuffer must: have been created with
ename:VK_BUFFER_USAGE_TRANSFER_DST_BIT usage flag
* [[VUID-vkCmdUpdateBuffer-dstBuffer-00035]]
If pname:dstBuffer is non-sparse then it must: be bound completely and
contiguously to a single sname:VkDeviceMemory object
* [[VUID-vkCmdUpdateBuffer-dstOffset-00036]]
pname:dstOffset must: be a multiple of `4`
* [[VUID-vkCmdUpdateBuffer-dataSize-00037]]
pname:dataSize must: be less than or equal to `65536`
* [[VUID-vkCmdUpdateBuffer-dataSize-00038]]
pname:dataSize must: be a multiple of `4`
ifdef::VK_VERSION_1_1[]
* [[VUID-vkCmdUpdateBuffer-commandBuffer-01813]]
If pname:commandBuffer is an unprotected command buffer, then
pname:dstBuffer must: not be a protected buffer
* [[VUID-vkCmdUpdateBuffer-commandBuffer-01814]]
If pname:commandBuffer is a protected command buffer, then
pname:dstBuffer must: not be an unprotected buffer
endif::VK_VERSION_1_1[]
****
include::../validity/protos/vkCmdUpdateBuffer.txt[]
--
[NOTE]
.Note
====
The pname:pData parameter was of type code:uint32_t* instead of code:void*
prior to version 1.0.19 of the Specification and dlink:VK_HEADER_VERSION 19
of the <<boilerplate-headers,Vulkan Header Files>>.
This was a historical anomaly, as the source data may be of other types.
====