Function Prototype

vkCmdWriteAccelerationStructuresPropertiesKHR

Write acceleration structure result parameters to query results.
primary / secondary
outside
compute
action

To query acceleration structure size parameters call:

void vkCmdWriteAccelerationStructuresPropertiesKHR(
    VkCommandBuffer commandBuffer,
    uint32_t accelerationStructureCount,
    const VkAccelerationStructureKHR* pAccelerationStructures,
    VkQueryType queryType,
    VkQueryPool queryPool,
    uint32_t firstQuery);
  • commandBuffer is the command buffer into which the command will be recorded.
  • accelerationStructureCount is the count of acceleration structures for which to query the property.
  • pAccelerationStructures is a pointer to an array of existing previously built acceleration structures.
  • queryType is a VkQueryType value specifying the type of queries managed by the pool.
  • queryPool is the query pool that will manage the results of the query.
  • firstQuery is the first query index within the query pool that will contain the accelerationStructureCount number of results.

Accesses to any of the acceleration structures listed in pAccelerationStructures must be synchronized with the VK_PIPELINE_STAGE_2_ACCELERATION_STRUCTURE_COPY_BIT_KHR

pipeline stage or the VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR

pipeline stage, and an access type of VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR.

  • If queryType is VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR, then the value written out is the number of bytes required by a compacted acceleration structure.
  • If queryType is VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR, then the value written out is the number of bytes required by a serialized acceleration structure.

Valid Usage

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-queryPool-02493

queryPool must have been created with a queryType matching queryType

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-queryPool-02494

The queries identified by queryPool and firstQuery must be unavailable

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-buffer-03736

The buffer used to create each acceleration structure in pAccelerationStructures must be bound to device memory

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-query-04880

The sum of firstQuery plus accelerationStructureCount must be less than or equal to the number of queries in queryPool

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-04964

All acceleration structures in pAccelerationStructures must have been built prior to the execution of this command

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-accelerationStructures-03431

All acceleration structures in pAccelerationStructures must have been built with VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_COMPACTION_BIT_KHR if queryType is VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-queryType-06742

queryType must be VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SIZE_KHR, VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_BOTTOM_LEVEL_POINTERS_KHR, VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR, or VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR

Valid Usage (Implicit)

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-parameter

pAccelerationStructures must be a valid pointer to an array of accelerationStructureCount valid VkAccelerationStructureKHR handles

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-commandBuffer-cmdpool

The VkCommandPool that commandBuffer was allocated from must support compute operations

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-renderpass

This command must only be called outside of a render pass instance

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-videocoding

This command must only be called outside of a video coding scope

VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-commonparent

Each of commandBuffer, queryPool, and the elements of pAccelerationStructures 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 ::