C Specification

The VkAccelerationStructureCreateInfoKHR structure is defined as:

// Provided by VK_KHR_acceleration_structure
typedef struct VkAccelerationStructureCreateInfoKHR {
    VkStructureType                          sType;
    const void*                              pNext;
    VkAccelerationStructureCreateFlagsKHR    createFlags;
    VkBuffer                                 buffer;
    VkDeviceSize                             offset;
    VkDeviceSize                             size;
    VkAccelerationStructureTypeKHR           type;
    VkDeviceAddress                          deviceAddress;
} VkAccelerationStructureCreateInfoKHR;

Members

  • sType is a VkStructureType value identifying this structure.

  • pNext is NULL or a pointer to a structure extending this structure.

  • createFlags is a bitmask of VkAccelerationStructureCreateFlagBitsKHR specifying additional creation parameters of the acceleration structure.

  • buffer is the buffer on which the acceleration structure will be stored.

  • offset is an offset in bytes from the base address of the buffer at which the acceleration structure will be stored, and must be a multiple of 256.

  • size is the size required for the acceleration structure.

  • type is a VkAccelerationStructureTypeKHR value specifying the type of acceleration structure that will be created.

  • deviceAddress is the device address requested for the acceleration structure, obtained from vkGetAccelerationStructureDeviceAddressKHR, if the accelerationStructureCaptureReplay feature is being used. If deviceAddress is zero, no specific address is requested.

Description

Applications should avoid creating acceleration structures with application-provided addresses and implementation-provided addresses in the same process, to reduce the likelihood of VK_ERROR_INVALID_OPAQUE_CAPTURE_ADDRESS_KHR errors.

Note

The expected usage for this is that a trace capture/replay tool will add the VK_BUFFER_CREATE_DEVICE_ADDRESS_CAPTURE_REPLAY_BIT flag to all buffers that use VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT, and will add VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT to all buffers used as storage for an acceleration structure where deviceAddress is not zero. This also means that the tool will need to add VK_MEMORY_ALLOCATE_DEVICE_ADDRESS_BIT to memory allocations to allow the flag to be set where the application may not have otherwise required it. During capture the tool will save the queried opaque device addresses in the trace. During replay, the buffers will be created specifying the original address so any address values stored in the trace data will remain valid.

Implementations are expected to separate such buffers in the GPU address space so normal allocations will avoid using these addresses. Applications and tools should avoid mixing application-provided and implementation-provided addresses for buffers created with VK_BUFFER_CREATE_DEVICE_ADDRESS_CAPTURE_REPLAY_BIT, to avoid address space allocation conflicts.

Applications should create an acceleration structure with a specific VkAccelerationStructureTypeKHR other than VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR.

Note

VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR is intended to be used by API translation layers. This can be used at acceleration structure creation time in cases where the actual acceleration structure type (top or bottom) is not yet known. The actual acceleration structure type must be specified as VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR or VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR when the build is performed.

If the acceleration structure will be the target of a build operation, the required size for an acceleration structure can be queried with vkGetAccelerationStructureBuildSizesKHR. If the acceleration structure is going to be the target of a compacting copy, vkCmdWriteAccelerationStructuresPropertiesKHR or vkWriteAccelerationStructuresPropertiesKHR can be used to obtain the compacted size required.

If the acceleration structure will be the target of a build operation with VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV it must include VK_ACCELERATION_STRUCTURE_CREATE_MOTION_BIT_NV in createFlags and include VkAccelerationStructureMotionInfoNV as an extension structure in pNext with the number of instances as metadata for the object.

Valid Usage
Valid Usage (Implicit)

See Also

VK_KHR_acceleration_structure, VkAccelerationStructureCreateFlagsKHR, VkAccelerationStructureTypeKHR, VkBuffer, VkDeviceAddress, VkDeviceSize, VkStructureType, vkCreateAccelerationStructureKHR

Document Notes

For more information, see the Vulkan Specification.

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2026 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0