org.lwjgl.vulkan

Class EXTTransformFeedback

java.lang.Object

org.lwjgl.vulkan.EXTTransformFeedback

public class EXTTransformFeedback
extends java.lang.Object

This extension adds transform feedback to the Vulkan API by exposing the SPIR-V TransformFeedback and GeometryStreams capabilities to capture vertex, tessellation or geometry shader outputs to one or more buffers. It adds API functionality to bind transform feedback buffers to capture the primitives emitted by the graphics pipeline from SPIR-V outputs decorated for transform feedback. The transform feedback capture can be paused and resumed by way of storing and retrieving a byte counter. The captured data can be drawn again where the vertex count is derived from the byte counter without CPU intervention. If the implementation is capable, a vertex stream other than zero can be rasterized.

All these features are designed to match the full capabilities of OpenGL core transform feedback functionality and beyond. Many of the features are optional to allow base OpenGL ES GPUs to also implement this extension.

The primary purpose of the functionality exposed by this extension is to support translation layers from other 3D APIs. This functionality is not considered forward looking, and is not expected to be promoted to a KHR extension or to core Vulkan. Unless this is needed for translation, it is recommended that developers use alternative techniques of using the GPU to process and capture vertex data.

Name String

VK_EXT_transform_feedback

Extension Type

Device extension

Registered Extension Number

29

Revision

1

Extension and Version Dependencies

• Requires Vulkan 1.0
• Requires VK_KHR_get_physical_device_properties2

Contact

• Piers Daniell pdaniell-nv

Last Modified Data

2018-10-09

Contributors

• Baldur Karlsson, Valve
• Boris Zanin, Mobica
• Daniel Rakos, AMD
• Donald Scorgie, Imagination
• Henri Verbeet, CodeWeavers
• Jan-Harald Fredriksen, Arm
• Jason Ekstrand, Intel
• Jeff Bolz, NVIDIA
• Jesse Barker, Unity
• Jesse Hall, Google
• Pierre-Loup Griffais, Valve
• Philip Rebohle, DXVK
• Ruihao Zhang, Qualcomm
• Samuel Pitoiset, Valve
• Slawomir Grajewski, Intel
• Stu Smith, Imagination Technologies

Field Summary

Fields

Modifier and Type	Field and Description
static int	VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT Extends VkAccessFlagBits.
static int	VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT Extends VkAccessFlagBits.
static int	VK_ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT Extends VkAccessFlagBits.
static int	VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT Extends VkBufferUsageFlagBits.
static int	VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT Extends VkBufferUsageFlagBits.
static java.lang.String	VK_EXT_TRANSFORM_FEEDBACK_EXTENSION_NAME The extension name.
static int	VK_EXT_TRANSFORM_FEEDBACK_SPEC_VERSION The extension specification version.
static int	VK_PIPELINE_STAGE_TRANSFORM_FEEDBACK_BIT_EXT Extends VkPipelineStageFlagBits.
static int	VK_QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT Extends VkQueryType.
static int	VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT Extends VkStructureType.
static int	VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT Extends VkStructureType.
static int	VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT Extends VkStructureType.

Method Summary

Modifier and Type	Method and Description
static void	nvkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, int counterBufferCount, long pCounterBuffers, long pCounterBufferOffsets) Unsafe version of: CmdBeginTransformFeedbackEXT
static void	nvkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstBinding, int bindingCount, long pBuffers, long pOffsets, long pSizes) Unsafe version of: CmdBindTransformFeedbackBuffersEXT
static void	nvkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, int counterBufferCount, long pCounterBuffers, long pCounterBufferOffsets) Unsafe version of: CmdEndTransformFeedbackEXT
static void	vkCmdBeginQueryIndexedEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, long queryPool, int query, int flags, int index) Begin an indexed query.
static void	vkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, long[] pCounterBuffers, long[] pCounterBufferOffsets) Array version of: CmdBeginTransformFeedbackEXT
static void	vkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, java.nio.LongBuffer pCounterBuffers, java.nio.LongBuffer pCounterBufferOffsets) Make transform feedback active in the command buffer.
static void	vkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstBinding, long[] pBuffers, long[] pOffsets, long[] pSizes) Array version of: CmdBindTransformFeedbackBuffersEXT
static void	vkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstBinding, java.nio.LongBuffer pBuffers, java.nio.LongBuffer pOffsets, java.nio.LongBuffer pSizes) Bind transform feedback buffers to a command buffer.
static void	vkCmdDrawIndirectByteCountEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int instanceCount, int firstInstance, long counterBuffer, long counterBufferOffset, int counterOffset, int vertexStride) Draw primitives where the vertex count is derived from the counter byte value in the counter buffer.
static void	vkCmdEndQueryIndexedEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, long queryPool, int query, int index) Ends a query.
static void	vkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, long[] pCounterBuffers, long[] pCounterBufferOffsets) Array version of: CmdEndTransformFeedbackEXT
static void	vkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer, int firstCounterBuffer, java.nio.LongBuffer pCounterBuffers, java.nio.LongBuffer pCounterBufferOffsets) Make transform feedback inactive in the command buffer.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VK_EXT_TRANSFORM_FEEDBACK_SPEC_VERSION

public static final int VK_EXT_TRANSFORM_FEEDBACK_SPEC_VERSION

The extension specification version.

See Also:

Constant Field Values

VK_EXT_TRANSFORM_FEEDBACK_EXTENSION_NAME

public static final java.lang.String VK_EXT_TRANSFORM_FEEDBACK_EXTENSION_NAME

The extension name.

See Also:

Constant Field Values

VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT

public static final int VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT

Extends VkStructureType.

Enum values:

• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT
• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT
• STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT

See Also:

Constant Field Values

VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT

public static final int VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT

Extends VkStructureType.

Enum values:

• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT
• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT
• STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT

See Also:

Constant Field Values

VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT

public static final int VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT

Extends VkStructureType.

Enum values:

• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_FEATURES_EXT
• STRUCTURE_TYPE_PHYSICAL_DEVICE_TRANSFORM_FEEDBACK_PROPERTIES_EXT
• STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_STREAM_CREATE_INFO_EXT

See Also:

Constant Field Values

VK_QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT

public static final int VK_QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT

Extends VkQueryType.

See Also:

Constant Field Values

VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT

public static final int VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT

Extends VkBufferUsageFlagBits.

Enum values:

• BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT
• BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT

See Also:

Constant Field Values

VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT

public static final int VK_BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT

Extends VkBufferUsageFlagBits.

Enum values:

• BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT
• BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT

See Also:

Constant Field Values

VK_ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT

public static final int VK_ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT

Extends VkAccessFlagBits.

Enum values:

• ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT

See Also:

Constant Field Values

VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT

public static final int VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT

Extends VkAccessFlagBits.

Enum values:

• ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT

See Also:

Constant Field Values

VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT

public static final int VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT

Extends VkAccessFlagBits.

Enum values:

• ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT
• ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT

See Also:

Constant Field Values

VK_PIPELINE_STAGE_TRANSFORM_FEEDBACK_BIT_EXT

public static final int VK_PIPELINE_STAGE_TRANSFORM_FEEDBACK_BIT_EXT

Extends VkPipelineStageFlagBits.

See Also:

Constant Field Values

Method Detail

nvkCmdBindTransformFeedbackBuffersEXT

public static void nvkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                         int firstBinding,
                                                         int bindingCount,
                                                         long pBuffers,
                                                         long pOffsets,
                                                         long pSizes)

Unsafe version of: CmdBindTransformFeedbackBuffersEXT

Parameters:

bindingCount - the number of transform feedback bindings whose state is updated by the command.

vkCmdBindTransformFeedbackBuffersEXT

public static void vkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                        int firstBinding,
                                                        java.nio.LongBuffer pBuffers,
                                                        java.nio.LongBuffer pOffsets,
                                                        @Nullable
                                                        java.nio.LongBuffer pSizes)

Bind transform feedback buffers to a command buffer.

C Specification

To bind transform feedback buffers to a command buffer for use in subsequent draw commands, call:

 void vkCmdBindTransformFeedbackBuffersEXT(
     VkCommandBuffer                             commandBuffer,
     uint32_t                                    firstBinding,
     uint32_t                                    bindingCount,
     const VkBuffer*                             pBuffers,
     const VkDeviceSize*                         pOffsets,
     const VkDeviceSize*                         pSizes);

Description

The values taken from elements i of pBuffers, pOffsets and pSizes replace the current state for the transform feedback binding firstBinding + i, for i in [0, bindingCount). The transform feedback binding is updated to start at the offset indicated by pOffsets[i] from the start of the buffer pBuffers[i].

Valid Usage

• VkPhysicalDeviceTransformFeedbackFeaturesEXT::transformFeedback must be enabled
• firstBinding must be less than VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• The sum of firstBinding and bindingCount must be less than or equal to VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• All elements of pOffsets must be less than the size of the corresponding element in pBuffers
• All elements of pOffsets must be a multiple of 4
• All elements of pBuffers must have been created with the BUFFER_USAGE_TRANSFORM_FEEDBACK_BUFFER_BIT_EXT flag
• If the optional pSize array is specified, each element of pSizes must either be WHOLE_SIZE, or be less than or equal to VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBufferSize
• All elements of pSizes must be less than or equal to the size of the corresponding buffer in pBuffers
• All elements of pOffsets plus pSizes, where the pSizes, element is not WHOLE_SIZE, must be less than or equal to the size of the corresponding element in pBuffers
• Each element of pBuffers that is non-sparse must be bound completely and contiguously to a single VkDeviceMemory object
• Transform feedback must not be active when the vkCmdBindTransformFeedbackBuffersEXT command is recorded

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• pBuffers must be a valid pointer to an array of bindingCount valid VkBuffer handles
• pOffsets must be a valid pointer to an array of bindingCount VkDeviceSize values
• If pSizes is not NULL, pSizes must be a valid pointer to an array of bindingCount VkDeviceSize values
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• If pSizes is not NULL, bindingCount must be greater than 0
• Both of commandBuffer, and the elements of pBuffers must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Both	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

firstBinding - the index of the first transform feedback binding whose state is updated by the command.

pBuffers - a pointer to an array of buffer handles.

pOffsets - a pointer to an array of buffer offsets.

pSizes - an optional array of buffer sizes, specifying the maximum number of bytes to capture to the corresponding transform feedback buffer. If pSizes is NULL, or the value of the pSizes array element is WHOLE_SIZE, then the maximum bytes captured will be the size of the corresponding buffer minus the buffer offset.

nvkCmdBeginTransformFeedbackEXT

public static void nvkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                   int firstCounterBuffer,
                                                   int counterBufferCount,
                                                   long pCounterBuffers,
                                                   long pCounterBufferOffsets)

Unsafe version of: CmdBeginTransformFeedbackEXT

Parameters:

counterBufferCount - the size of the pCounterBuffers and pCounterBufferOffsets arrays.

vkCmdBeginTransformFeedbackEXT

public static void vkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                  int firstCounterBuffer,
                                                  @Nullable
                                                  java.nio.LongBuffer pCounterBuffers,
                                                  @Nullable
                                                  java.nio.LongBuffer pCounterBufferOffsets)

Make transform feedback active in the command buffer.

C Specification

Transform feedback for specific transform feedback buffers is made active by calling:

 void vkCmdBeginTransformFeedbackEXT(
     VkCommandBuffer                             commandBuffer,
     uint32_t                                    firstCounterBuffer,
     uint32_t                                    counterBufferCount,
     const VkBuffer*                             pCounterBuffers,
     const VkDeviceSize*                         pCounterBufferOffsets);

Description

The active transform feedback buffers will capture primitives emitted from the corresponding XfbBuffer in the bound graphics pipeline. Any XfbBuffer emitted that does not output to an active transform feedback buffer will not be captured.

Valid Usage

• VkPhysicalDeviceTransformFeedbackFeaturesEXT::transformFeedback must be enabled
• Transform feedback must not be active
• firstCounterBuffer must be less than VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• The sum of firstCounterBuffer and counterBufferCount must be less than or equal to VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• If counterBufferCount is not 0, and pCounterBuffers is not NULL, pCounterBuffers must be a valid pointer to an array of counterBufferCount VkBuffer handles that are either valid or NULL_HANDLE
• For each buffer handle in the array, if it is not NULL_HANDLE it must reference a buffer large enough to hold 4 bytes at the corresponding offset from the pCounterBufferOffsets array
• If pCounterBuffer is NULL, then pCounterBufferOffsets must also be NULL
• For each buffer handle in the pCounterBuffers array that is not NULL_HANDLE it must have been created with a usage value containing BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT
• Transform feedback must not be made active in a render pass instance with multiview enabled

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• If counterBufferCount is not 0, and pCounterBufferOffsets is not NULL, pCounterBufferOffsets must be a valid pointer to an array of counterBufferCount VkDeviceSize values
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• This command must only be called inside of a render pass instance
• Both of commandBuffer, and the elements of pCounterBuffers that are valid handles of non-ignored parameters must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Inside	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

firstCounterBuffer - the index of the first transform feedback buffer corresponding to pCounterBuffers[0] and pCounterBufferOffsets[0].

pCounterBuffers - an optional array of buffer handles to the counter buffers which contain a 4 byte integer value representing the byte offset from the start of the corresponding transform feedback buffer from where to start capturing vertex data. If the byte offset stored to the counter buffer location was done using CmdEndTransformFeedbackEXT it can be used to resume transform feedback from the previous location. If pCounterBuffers is NULL, then transform feedback will start capturing vertex data to byte offset zero in all bound transform feedback buffers. For each element of pCounterBuffers that is NULL_HANDLE, transform feedback will start capturing vertex data to byte zero in the corresponding bound transform feedback buffer.

pCounterBufferOffsets - an optional array of offsets within each of the pCounterBuffers where the counter values were previously written. The location in each counter buffer at these offsets must be large enough to contain 4 bytes of data. This data is the number of bytes captured by the previous transform feedback to this buffer. If pCounterBufferOffsets is NULL, then it is assumed the offsets are zero.

nvkCmdEndTransformFeedbackEXT

public static void nvkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                 int firstCounterBuffer,
                                                 int counterBufferCount,
                                                 long pCounterBuffers,
                                                 long pCounterBufferOffsets)

Unsafe version of: CmdEndTransformFeedbackEXT

Parameters:

counterBufferCount - the size of the pCounterBuffers and pCounterBufferOffsets arrays.

vkCmdEndTransformFeedbackEXT

public static void vkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                int firstCounterBuffer,
                                                @Nullable
                                                java.nio.LongBuffer pCounterBuffers,
                                                @Nullable
                                                java.nio.LongBuffer pCounterBufferOffsets)

Make transform feedback inactive in the command buffer.

C Specification

Transform feedback for specific transform feedback buffers is made inactive by calling:

 void vkCmdEndTransformFeedbackEXT(
     VkCommandBuffer                             commandBuffer,
     uint32_t                                    firstCounterBuffer,
     uint32_t                                    counterBufferCount,
     const VkBuffer*                             pCounterBuffers,
     const VkDeviceSize*                         pCounterBufferOffsets);

Valid Usage

• VkPhysicalDeviceTransformFeedbackFeaturesEXT::transformFeedback must be enabled
• Transform feedback must be active
• firstCounterBuffer must be less than VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• The sum of firstCounterBuffer and counterBufferCount must be less than or equal to VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackBuffers
• If counterBufferCount is not 0, and pCounterBuffers is not NULL, pCounterBuffers must be a valid pointer to an array of counterBufferCount VkBuffer handles that are either valid or NULL_HANDLE
• For each buffer handle in the array, if it is not NULL_HANDLE it must reference a buffer large enough to hold 4 bytes at the corresponding offset from the pCounterBufferOffsets array
• If pCounterBuffer is NULL, then pCounterBufferOffsets must also be NULL
• For each buffer handle in the pCounterBuffers array that is not NULL_HANDLE it must have been created with a usage value containing BUFFER_USAGE_TRANSFORM_FEEDBACK_COUNTER_BUFFER_BIT_EXT

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• If counterBufferCount is not 0, and pCounterBufferOffsets is not NULL, pCounterBufferOffsets must be a valid pointer to an array of counterBufferCount VkDeviceSize values
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• This command must only be called inside of a render pass instance
• Both of commandBuffer, and the elements of pCounterBuffers that are valid handles of non-ignored parameters must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Inside	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

firstCounterBuffer - the index of the first transform feedback buffer corresponding to pCounterBuffers[0] and pCounterBufferOffsets[0].

pCounterBuffers - an optional array of buffer handles to the counter buffers used to record the current byte positions of each transform feedback buffer where the next vertex output data would be captured. This can be used by a subsequent CmdBeginTransformFeedbackEXT call to resume transform feedback capture from this position. It can also be used by CmdDrawIndirectByteCountEXT to determine the vertex count of the draw call.

pCounterBufferOffsets - an optional array of offsets within each of the pCounterBuffers where the counter values can be written. The location in each counter buffer at these offsets must be large enough to contain 4 bytes of data. The data stored at this location is the byte offset from the start of the transform feedback buffer binding where the next vertex data would be written. If pCounterBufferOffsets is NULL, then it is assumed the offsets are zero.

vkCmdBeginQueryIndexedEXT

public static void vkCmdBeginQueryIndexedEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                             long queryPool,
                                             int query,
                                             int flags,
                                             int index)

Begin an indexed query.

C Specification

To begin an indexed query, call:

 void vkCmdBeginQueryIndexedEXT(
     VkCommandBuffer                             commandBuffer,
     VkQueryPool                                 queryPool,
     uint32_t                                    query,
     VkQueryControlFlags                         flags,
     uint32_t                                    index);

Description

The vkCmdBeginQueryIndexedEXT command operates the same as the CmdBeginQuery command, except that it also accepts a query type specific index parameter.

Valid Usage

• queryPool must have been created with a queryType that differs from that of any queries that are active within commandBuffer
• All queries used by the command must be unavailable
• The queryType used to create queryPool must not be QUERY_TYPE_TIMESTAMP
• If the precise occlusion queries feature is not enabled, or the queryType used to create queryPool was not QUERY_TYPE_OCCLUSION, flags must not contain QUERY_CONTROL_PRECISE_BIT
• query must be less than the number of queries in queryPool
• If the queryType used to create queryPool was QUERY_TYPE_OCCLUSION, the VkCommandPool that commandBuffer was allocated from must support graphics operations
• If the queryType used to create queryPool was QUERY_TYPE_PIPELINE_STATISTICS and any of the pipelineStatistics indicate graphics operations, the VkCommandPool that commandBuffer was allocated from must support graphics operations
• If the queryType used to create queryPool was QUERY_TYPE_PIPELINE_STATISTICS and any of the pipelineStatistics indicate compute operations, the VkCommandPool that commandBuffer was allocated from must support compute operations
• commandBuffer must not be a protected command buffer
• If called within a render pass instance, the sum of query and the number of bits set in the current subpass’s view mask must be less than or equal to the number of queries in queryPool
• If the queryType used to create queryPool was QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the VkCommandPool that commandBuffer was allocated from must support graphics operations
• If the queryType used to create queryPool was QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the index parameter must be less than VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackStreams
• If the queryType used to create queryPool was not QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the index must be zero
• If the queryType used to create queryPool was QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT then VkPhysicalDeviceTransformFeedbackPropertiesEXT::transformFeedbackQueries must be supported
• If queryPool was created with a queryType of QUERY_TYPE_PERFORMANCE_QUERY_KHR, the profiling lock must have been held before BeginCommandBuffer was called on commandBuffer
• If queryPool was created with a queryType of QUERY_TYPE_PERFORMANCE_QUERY_KHR and one of the counters used to create queryPool was QUERY_SCOPE_COMMAND_BUFFER_KHR, the query begin must be the first recorded command in commandBuffer
• If queryPool was created with a queryType of QUERY_TYPE_PERFORMANCE_QUERY_KHR and one of the counters used to create queryPool was QUERY_SCOPE_RENDER_PASS_KHR, the begin command must not be recorded within a render pass instance
• If queryPool was created with a queryType of QUERY_TYPE_PERFORMANCE_QUERY_KHR and another query pool with a queryType QUERY_TYPE_PERFORMANCE_QUERY_KHR has been used within commandBuffer, its parent primary command buffer or secondary command buffer recorded within the same parent primary command buffer as commandBuffer, the performanceCounterMultipleQueryPools feature must be enabled

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• queryPool must be a valid VkQueryPool handle
• flags must be a valid combination of VkQueryControlFlagBits values
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics, or compute operations
• Both of commandBuffer, and queryPool must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Both	Graphics Compute

Parameters:

commandBuffer - the command buffer into which this command will be recorded.

queryPool - the query pool that will manage the results of the query.

query - the query index within the query pool that will contain the results.

flags - a bitmask of VkQueryControlFlagBits specifying constraints on the types of queries that can be performed.

index - the query type specific index. When the query type is QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the index represents the vertex stream.

vkCmdEndQueryIndexedEXT

public static void vkCmdEndQueryIndexedEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                           long queryPool,
                                           int query,
                                           int index)

Ends a query.

C Specification

To end an indexed query after the set of desired draw or dispatch commands is recorded, call:

 void vkCmdEndQueryIndexedEXT(
     VkCommandBuffer                             commandBuffer,
     VkQueryPool                                 queryPool,
     uint32_t                                    query,
     uint32_t                                    index);

Description

The vkCmdEndQueryIndexedEXT command operates the same as the CmdEndQuery command, except that it also accepts a query type specific index parameter.

Valid Usage

• All queries used by the command must be active
• query must be less than the number of queries in queryPool
• commandBuffer must not be a protected command buffer
• If vkCmdEndQueryIndexedEXT is called within a render pass instance, the sum of query and the number of bits set in the current subpass’s view mask must be less than or equal to the number of queries in queryPool
• If the queryType used to create queryPool was QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the index parameter must be less than VkPhysicalDeviceTransformFeedbackPropertiesEXT::maxTransformFeedbackStreams
• If the queryType used to create queryPool was not QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT the index must be zero
• If the queryType used to create queryPool was QUERY_TYPE_TRANSFORM_FEEDBACK_STREAM_EXT index must equal the index used to begin the query

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• queryPool must be a valid VkQueryPool handle
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics, or compute operations
• Both of commandBuffer, and queryPool must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Both	Graphics Compute

Parameters:

commandBuffer - the command buffer into which this command will be recorded.

queryPool - the query pool that is managing the results of the query.

query - the query index within the query pool where the result is stored.

index - the query type specific index.

vkCmdDrawIndirectByteCountEXT

public static void vkCmdDrawIndirectByteCountEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                 int instanceCount,
                                                 int firstInstance,
                                                 long counterBuffer,
                                                 long counterBufferOffset,
                                                 int counterOffset,
                                                 int vertexStride)

Draw primitives where the vertex count is derived from the counter byte value in the counter buffer.

C Specification

To record a non-indexed draw call, where the vertex count is based on a byte count read from a buffer and the passed in vertex stride parameter, call:

 void vkCmdDrawIndirectByteCountEXT(
     VkCommandBuffer                             commandBuffer,
     uint32_t                                    instanceCount,
     uint32_t                                    firstInstance,
     VkBuffer                                    counterBuffer,
     VkDeviceSize                                counterBufferOffset,
     uint32_t                                    counterOffset,
     uint32_t                                    vertexStride);

Description

When the command is executed, primitives are assembled in the same way as done with CmdDraw except the vertexCount is calculated based on the byte count read from counterBuffer at offset counterBufferOffset. The assembled primitives execute the bound graphics pipeline.

The effective vertexCount is calculated as follows:

 const uint32_t * counterBufferPtr = (const uint8_t *)counterBuffer.address + counterBufferOffset;
 vertexCount = floor(max(0, (*counterBufferPtr - counterOffset)) / vertexStride);

The effective firstVertex is zero.

Valid Usage

• If a VkImageView is sampled with FILTER_LINEAR as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_LINEAR_BIT
• If a VkImageView is accessed using atomic operations as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_STORAGE_IMAGE_ATOMIC_BIT
• If a VkImageView is sampled with FILTER_CUBIC_EXT as a result of this command, then the image view’s format features must contain FORMAT_FEATURE_SAMPLED_IMAGE_FILTER_CUBIC_BIT_EXT
• Any VkImageView being sampled with FILTER_CUBIC_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubic returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImageView being sampled with FILTER_CUBIC_EXT with a reduction mode of either SAMPLER_REDUCTION_MODE_MIN_EXT or SAMPLER_REDUCTION_MODE_MAX_EXT as a result of this command must have a VkImageViewType and format that supports cubic filtering together with minmax filtering, as specified by VkFilterCubicImageViewImageFormatPropertiesEXT::filterCubicMinmax returned by vkGetPhysicalDeviceImageFormatProperties2
• Any VkImage created with a VkImageCreateInfo::flags containing IMAGE_CREATE_CORNER_SAMPLED_BIT_NV sampled as a result of this command must only be sampled using a VkSamplerAddressMode of SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE.
• For each set n that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a descriptor set must have been bound to n at the same pipeline bind point, with a VkPipelineLayout that is compatible for set n, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• For each push constant that is statically used by the VkPipeline bound to the pipeline bind point used by this command, a push constant value must have been set for the same pipeline bind point, with a VkPipelineLayout that is compatible for push constants, with the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout Compatibility
• Descriptors in each bound descriptor set, specified via vkCmdBindDescriptorSets, must be valid if they are statically used by the VkPipeline bound to the pipeline bind point used by this command
• A valid pipeline must be bound to the pipeline bind point used by this command
• If the VkPipeline object bound to the pipeline bind point used by this command requires any dynamic state, that state must have been set for commandBuffer
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used to sample from any VkImage with a VkImageView of the type IMAGE_VIEW_TYPE_3D, IMAGE_VIEW_TYPE_CUBE, IMAGE_VIEW_TYPE_1D_ARRAY, IMAGE_VIEW_TYPE_2D_ARRAY or IMAGE_VIEW_TYPE_CUBE_ARRAY, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions with ImplicitLod, Dref or Proj in their name, in any shader stage
• If the VkPipeline object bound to the pipeline bind point used by this command accesses a VkSampler object that uses unnormalized coordinates, that sampler must not be used with any of the SPIR-V OpImageSample* or OpImageSparseSample* instructions that includes a LOD bias or any offset values, in any shader stage
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a uniform buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If the robust buffer access feature is not enabled, and if the VkPipeline object bound to the pipeline bind point used by this command accesses a storage buffer, it must not access values outside of the range of the buffer as specified in the descriptor set bound to the same pipeline bind point
• If commandBuffer is an unprotected command buffer, any resource accessed by the VkPipeline object bound to the pipeline bind point used by this command must not be a protected resource
• The current render pass must be compatible with the renderPass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• The subpass index of the current render pass must be equal to the subpass member of the VkGraphicsPipelineCreateInfo structure specified when creating the VkPipeline bound to PIPELINE_BIND_POINT_GRAPHICS.
• Every input attachment used by the current subpass must be bound to the pipeline via a descriptor set
• Image subresources used as attachments in the current render pass must not be accessed in any way other than as an attachment by this command.
• If the draw is recorded in a render pass instance with multiview enabled, the maximum instance index must be less than or equal to VkPhysicalDeviceMultiviewProperties::maxMultiviewInstanceIndex.
• If the bound graphics pipeline was created with VkPipelineSampleLocationsStateCreateInfoEXT::sampleLocationsEnable set to TRUE and the current subpass has a depth/stencil attachment, then that attachment must have been created with the IMAGE_CREATE_SAMPLE_LOCATIONS_COMPATIBLE_DEPTH_BIT_EXT bit set
• All vertex input bindings accessed via vertex input variables declared in the vertex shader entry point’s interface must have valid buffers bound
• For a given vertex buffer binding, any attribute data fetched must be entirely contained within the corresponding vertex buffer binding, as described in Vertex Input Description
• VkPhysicalDeviceTransformFeedbackFeaturesEXT::transformFeedback must be enabled
• The implementation must support VkPhysicalDeviceTransformFeedbackPropertiesEXT::transformFeedbackDraw
• vertexStride must be greater than 0 and less than or equal to VkPhysicalDeviceLimits::maxTransformFeedbackBufferDataStride
• counterBuffer must have been created with the BUFFER_USAGE_INDIRECT_BUFFER_BIT bit set
• commandBuffer must not be a protected command buffer

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• counterBuffer must be a valid VkBuffer handle
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics operations
• This command must only be called inside of a render pass instance
• Both of commandBuffer, and counterBuffer must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

Command Buffer Levels	Render Pass Scope	Supported Queue Types	Pipeline Type
Primary Secondary	Inside	Graphics	Graphics

Parameters:

commandBuffer - the command buffer into which the command is recorded.

instanceCount - the number of instances to draw.

firstInstance - the instance ID of the first instance to draw.

counterBuffer - the buffer handle from where the byte count is read.

counterBufferOffset - the offset into the buffer used to read the byte count, which is used to calculate the vertex count for this draw call.

counterOffset - subtracted from the byte count read from the counterBuffer at the counterBufferOffset

vertexStride - the stride in bytes between each element of the vertex data that is used to calculate the vertex count from the counter value. This value is typically the same value that was used in the graphics pipeline state when the transform feedback was captured as the XfbStride.

vkCmdBindTransformFeedbackBuffersEXT

public static void vkCmdBindTransformFeedbackBuffersEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                        int firstBinding,
                                                        long[] pBuffers,
                                                        long[] pOffsets,
                                                        @Nullable
                                                        long[] pSizes)

Array version of: CmdBindTransformFeedbackBuffersEXT

vkCmdBeginTransformFeedbackEXT

public static void vkCmdBeginTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                  int firstCounterBuffer,
                                                  @Nullable
                                                  long[] pCounterBuffers,
                                                  @Nullable
                                                  long[] pCounterBufferOffsets)

Array version of: CmdBeginTransformFeedbackEXT

vkCmdEndTransformFeedbackEXT

public static void vkCmdEndTransformFeedbackEXT(org.lwjgl.vulkan.VkCommandBuffer commandBuffer,
                                                int firstCounterBuffer,
                                                @Nullable
                                                long[] pCounterBuffers,
                                                @Nullable
                                                long[] pCounterBufferOffsets)

Array version of: CmdEndTransformFeedbackEXT