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GHC 9.14.1 · lts/ghc-9.14.x · 3e2d568 · 2026-10-11

Modulevulkan-3.27GHC2021

Vulkan.Core10.Query

  • 9 types
  • 4 values
  • Packagevulkan-3.27
  • Exports48
  • LanguageGHC2021
  • LicenceBSD-3-Clause
  • SourceQuery.hs
valuecreateQueryPool
  1. :: (Extendss QueryPoolCreateInfo a, PokeChain a, MonadIO io)
  2. => Device

    device is the logical device that creates the query pool.

  3. -> QueryPoolCreateInfo a

    pCreateInfo is a pointer to a QueryPoolCreateInfo structure containing the number and type of queries to be managed by the pool.

  4. -> "allocator" ::: Maybe AllocationCallbacks

    pAllocator controls host memory allocation as described in the Memory Allocation chapter.

  5. -> io QueryPool
#

vkCreateQueryPool - Create a new query pool object

Valid Usage

Valid Usage (Implicit)

  • device must be a valid Device handle

  • pCreateInfo must be a valid pointer to a valid QueryPoolCreateInfo structure

  • If pAllocator is not NULL, pAllocator must be a valid pointer to a valid AllocationCallbacks structure

  • pQueryPool must be a valid pointer to a QueryPool handle

  • The device must have been created with at least 1 queue

Return Codes

Success
Failure

See Also

VK_VERSION_1_0, AllocationCallbacks, Device, QueryPool, QueryPoolCreateInfo

A convenience wrapper to make a compatible pair of calls to createQueryPool and destroyQueryPool

To ensure that destroyQueryPool is always called: pass bracket (or the allocate function from your favourite resource management library) as the last argument. To just extract the pair pass (,) as the last argument.

valuedestroyQueryPool
  1. :: MonadIO io
  2. => Device

    device is the logical device that destroys the query pool.

  3. -> QueryPool

    queryPool is the query pool to destroy.

  4. -> "allocator" ::: Maybe AllocationCallbacks

    pAllocator controls host memory allocation as described in the Memory Allocation chapter.

  5. -> io ()
#

vkDestroyQueryPool - Destroy a query pool object

Valid Usage

  • All submitted commands that refer to queryPool must have completed execution

  • If AllocationCallbacks were provided when queryPool was created, a compatible set of callbacks must be provided here

  • If no AllocationCallbacks were provided when queryPool was created, pAllocator must be NULL

Applications can verify that queryPool can be destroyed by checking that getQueryPoolResults() without the QUERY_RESULT_PARTIAL_BIT flag returns SUCCESS for all queries that are used in command buffers submitted for execution.

Valid Usage (Implicit)

  • device must be a valid Device handle

  • If queryPool is not NULL_HANDLE, queryPool must be a valid QueryPool handle

  • If pAllocator is not NULL, pAllocator must be a valid pointer to a valid AllocationCallbacks structure

  • If queryPool is a valid handle, it must have been created, allocated, or retrieved from device

Host Synchronization

  • Host access to queryPool must be externally synchronized

See Also

VK_VERSION_1_0, AllocationCallbacks, Device, QueryPool

valuegetQueryPoolResults
  1. :: MonadIO io
  2. => Device

    device is the logical device that owns the query pool.

  3. -> QueryPool

    queryPool is the query pool managing the queries containing the desired results.

  4. -> "firstQuery" ::: Word32

    firstQuery is the initial query index.

  5. -> "queryCount" ::: Word32

    queryCount is the number of queries to read.

  6. -> "dataSize" ::: Word64

    dataSize is the size in bytes of the buffer pointed to by pData.

  7. -> "data" ::: Ptr ()

    pData is a pointer to an application-allocated buffer where the results will be written

  8. -> "stride" ::: DeviceSize

    stride is the stride in bytes between results for individual queries within pData.

  9. -> QueryResultFlags

    flags is a bitmask of QueryResultFlagBits specifying how and when results are returned.

  10. -> io Result
#

vkGetQueryPoolResults - Copy results of queries in a query pool to a host memory region

Description

Any results written for a query are written according to a layout dependent on the query type.

If no bits are set in flags, and all requested queries are in the available state, results are written as an array of 32-bit unsigned integer values. Behavior when not all queries are available is described below.

If QUERY_RESULT_WITH_AVAILABILITY_BIT is set, results for all queries in queryPool identified by firstQuery and queryCount are copied to pData, along with an extra availability or status value written directly after the results of each query and interpreted as an unsigned integer. A value of zero indicates that the results are not yet available, otherwise the query is complete and results are available. The size of the availability or status values is 64 bits if QUERY_RESULT_64_BIT is set in flags. Otherwise, it is 32 bits.

If VK_QUERY_RESULT_WITH_STATUS_BIT_KHR is set, results for all queries in queryPool identified by firstQuery and queryCount are copied to pData, along with an extra status value written directly after the results of each query and interpreted as a signed integer. A value of zero indicates that the results are not yet available. Positive values indicate that the operations within the query completed successfully, and the query results are valid. Negative values indicate that the operations within the query completed unsuccessfully.

VkQueryResultStatusKHR defines specific meaning for values returned here, though implementations are free to return other values.

If the status value written is negative, indicating that the operations within the query completed unsuccessfully, then all other results written by this command are undefined unless otherwise specified for any of the results of the used query type.

If QUERY_RESULT_WITH_AVAILABILITY_BIT or VK_QUERY_RESULT_WITH_STATUS_BIT_KHR is set, the layout of data in the buffer is a (result,availability) or (result,status) pair for each query returned, and stride is the stride between each pair.

Results for any available query written by this command are final and represent the final result of the query. If QUERY_RESULT_PARTIAL_BIT is set, then for any query that is unavailable, an intermediate result between zero and the final result value is written for that query. Otherwise, any result written by this command is undefined.

If QUERY_RESULT_64_BIT is set, results and, if returned, availability or status values for all queries are written as an array of 64-bit values. If the queryPool was created with QUERY_TYPE_PERFORMANCE_QUERY_KHR, results for each query are written as an array of the type indicated by PerformanceCounterKHR::storage for the counter being queried. Otherwise, results and availability or status values are written as an array of 32-bit values. If an unsigned integer query’s value overflows the result type, the value may either wrap or saturate. If the maintenance7 feature is enabled, for an unsigned integer query, the 32-bit result value must be equal to the 32 least significant bits of the equivalent 64-bit result value. If a signed integer query’s value overflows the result type, the value is undefined. If a floating-point query’s value is not representable as the result type, the value is undefined.

If QUERY_RESULT_WAIT_BIT is set, this command defines an execution dependency with any earlier commands that writes one of the identified queries. The first synchronization scope includes all instances of cmdEndQuery, cmdEndQueryIndexedEXT, cmdWriteAccelerationStructuresPropertiesKHR, cmdWriteAccelerationStructuresPropertiesNV, cmdWriteMicromapsPropertiesEXT, cmdWriteTimestamp2, and cmdWriteTimestamp that reference any query in queryPool indicated by firstQuery and queryCount. The second synchronization scope includes the host operations of this command.

If QUERY_RESULT_WAIT_BIT is not set, getQueryPoolResults may return NOT_READY if there are queries in the unavailable state.

Applications must take care to ensure that use of the QUERY_RESULT_WAIT_BIT bit has the desired effect.

For example, if a query has been used previously and a command buffer records the commands cmdResetQueryPool, cmdBeginQuery, and cmdEndQuery for that query, then the query will remain in the available state until resetQueryPool is called or the cmdResetQueryPool command executes on a queue. Applications can use fences or events to ensure that a query has already been reset before checking for its results or availability status. Otherwise, a stale value could be returned from a previous use of the query.

The above also applies when QUERY_RESULT_WAIT_BIT is used in combination with QUERY_RESULT_WITH_AVAILABILITY_BIT. In this case, the returned availability status may reflect the result of a previous use of the query unless resetQueryPool is called or the cmdResetQueryPool command has been executed since the last use of the query.

A similar situation can arise with the VK_QUERY_RESULT_WITH_STATUS_BIT_KHR flag.

Applications can double-buffer query pool usage, with a pool per frame, and reset queries at the end of the frame in which they are read.

Valid Usage

  • firstQuery must be less than the number of queries in queryPool

Valid Usage (Implicit)

  • device must be a valid Device handle

  • queryPool must be a valid QueryPool handle

  • pData must be a valid pointer to an array of dataSize bytes

  • flags must be a valid combination of QueryResultFlagBits values

  • dataSize must be greater than 0

  • queryPool must have been created, allocated, or retrieved from device

Return Codes

Success
Failure

See Also

VK_VERSION_1_0, Device, DeviceSize, QueryPool, QueryResultFlags

datadata QueryPoolCreateInfo (es :: [Type])
#

VkQueryPoolCreateInfo - Structure specifying parameters of a newly created query pool

Valid Usage

Valid Usage (Implicit)

See Also

VK_VERSION_1_0, QueryPipelineStatisticFlags, QueryPoolCreateFlags, QueryType, StructureType, createQueryPool

Constructors

Instances5Extensible, Show, FromCStruct, ToCStruct, Zero
newtypenewtype QueryPool
#
Instances7Eq, Ord, Show, Storable, HasObjectType, IsHandle, …
newtypenewtype QueryType
#

VkQueryType - Specify the type of queries managed by a query pool

Description

See Also

VK_VERSION_1_0, QueryPoolCreateInfo, cmdWriteAccelerationStructuresPropertiesKHR, cmdWriteAccelerationStructuresPropertiesNV, cmdWriteMicromapsPropertiesEXT, writeAccelerationStructuresPropertiesKHR, writeMicromapsPropertiesEXT

Constructors

Instances6Eq, Ord, Read, Show, Storable, Zero
  • Eq QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
  • Ord QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
  • Read QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
  • Show QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
  • Storable QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
  • Zero QueryTypeDefined in vulkan-3.27 · Vulkan.Core10.Enums.QueryType
newtypenewtype QueryResultFlagBits
#

VkQueryResultFlagBits - Bitmask specifying how and when query results are returned

Description

  • QUERY_RESULT_64_BIT specifies the results will be written as an array of 64-bit unsigned integer values. If this bit is not set, the results will be written as an array of 32-bit unsigned integer values.

See Also

VK_VERSION_1_0, QueryResultFlags

Instances8Eq, Ord, Read, Show, Bits, FiniteBits, …

VkQueryPipelineStatisticFlagBits - Bitmask specifying queried pipeline statistics

Description

  • QUERY_PIPELINE_STATISTIC_INPUT_ASSEMBLY_PRIMITIVES_BIT specifies that queries managed by the pool will count the number of primitives processed by the input assembly stage. If primitive restart is enabled, restarting the primitive topology has no effect on the count. Incomplete primitives may be counted.

  • QUERY_PIPELINE_STATISTIC_VERTEX_SHADER_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of vertex shader invocations. This counter’s value is incremented each time a vertex shader is invoked.

  • QUERY_PIPELINE_STATISTIC_GEOMETRY_SHADER_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of geometry shader invocations. This counter’s value is incremented each time a geometry shader is invoked. In the case of instanced geometry shaders, the geometry shader invocations count is incremented for each separate instanced invocation.

  • QUERY_PIPELINE_STATISTIC_GEOMETRY_SHADER_PRIMITIVES_BIT specifies that queries managed by the pool will count the number of primitives generated by geometry shader invocations. The counter’s value is incremented each time the geometry shader emits a primitive. Restarting primitive topology using the SPIR-V instructions OpEndPrimitive or OpEndStreamPrimitive has no effect on the geometry shader output primitives count.

  • QUERY_PIPELINE_STATISTIC_CLIPPING_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of primitives processed by the Primitive Clipping stage of the pipeline. The counter’s value is incremented each time a primitive reaches the primitive clipping stage.

  • QUERY_PIPELINE_STATISTIC_CLIPPING_PRIMITIVES_BIT specifies that queries managed by the pool will count the number of primitives output by the Primitive Clipping stage of the pipeline. The counter’s value is incremented each time a primitive passes the primitive clipping stage. The actual number of primitives output by the primitive clipping stage for a particular input primitive is implementation-dependent but must satisfy the following conditions:

    • If at least one vertex of the input primitive lies inside the clipping volume, the counter is incremented by one or more.

    • Otherwise, the counter is incremented by zero or more.

  • QUERY_PIPELINE_STATISTIC_FRAGMENT_SHADER_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of fragment shader invocations. The counter’s value is incremented each time the fragment shader is invoked.

  • QUERY_PIPELINE_STATISTIC_TESSELLATION_CONTROL_SHADER_PATCHES_BIT specifies that queries managed by the pool will count the number of patches processed by the tessellation control shader. The counter’s value is incremented once for each patch for which a tessellation control shader is invoked.

  • QUERY_PIPELINE_STATISTIC_TESSELLATION_EVALUATION_SHADER_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of invocations of the tessellation evaluation shader. The counter’s value is incremented each time the tessellation evaluation shader is invoked.

  • QUERY_PIPELINE_STATISTIC_COMPUTE_SHADER_INVOCATIONS_BIT specifies that queries managed by the pool will count the number of compute shader invocations. The counter’s value is incremented every time the compute shader is invoked. Implementations may skip the execution of certain compute shader invocations or execute additional compute shader invocations for implementation-dependent reasons as long as the results of rendering otherwise remain unchanged.

  • QUERY_PIPELINE_STATISTIC_TASK_SHADER_INVOCATIONS_BIT_EXT specifies that queries managed by the pool will count the number of task shader invocations. The counter’s value is incremented every time the task shader is invoked.

  • QUERY_PIPELINE_STATISTIC_MESH_SHADER_INVOCATIONS_BIT_EXT specifies that queries managed by the pool will count the number of mesh shader invocations. The counter’s value is incremented every time the mesh shader is invoked.

These values are intended to measure relative statistics on one implementation. Various device architectures will count these values differently. Any or all counters may be affected by the issues described in Query Operation.

This counting difference is especially true if the pipeline contains mesh or task shaders, which may affect several of the counters in unexpected ways.

For example, tile-based rendering devices may need to replay the scene multiple times, affecting some of the counts.

If a pipeline has rasterizerDiscardEnable enabled, implementations may discard primitives after the final pre-rasterization shader stage. As a result, if rasterizerDiscardEnable is enabled, the clipping input and output primitives counters may not be incremented.

When a pipeline statistics query finishes, the result for that query is marked as available. The application can copy the result to a buffer (via cmdCopyQueryPoolResults), or request it be put into host memory (via getQueryPoolResults).

See Also

VK_VERSION_1_0, QueryPipelineStatisticFlags

Instances8Eq, Ord, Read, Show, Bits, FiniteBits, …
newtypenewtype QueryPoolCreateFlagBits
#

VkQueryPoolCreateFlagBits - Bitmask specifying query pool properties

Description

See Also

VK_VERSION_1_0, QueryPoolCreateFlags

Instances8Eq, Ord, Read, Show, Bits, FiniteBits, …