C Specification

To query the 64-bit device address for an acceleration structure, call:

// Provided by VK_KHR_acceleration_structure
VkDeviceAddress vkGetAccelerationStructureDeviceAddressKHR(
    VkDevice                                    device,
    const VkAccelerationStructureDeviceAddressInfoKHR* pInfo);

Parameters

  • device is the logical device that the acceleration structure was created on.

  • pInfo is a pointer to a VkAccelerationStructureDeviceAddressInfoKHR structure specifying the acceleration structure to retrieve an address for.

Description

The 64-bit return value is an address of the acceleration structure, which can be used for device and shader operations that involve acceleration structures, such as ray traversal and acceleration structure building.

If the acceleration structure was created with a non-zero value of VkAccelerationStructureCreateInfoKHR::deviceAddress, the return value will be the same address.

If the acceleration structure was created with a type of VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR, the returned address must be consistent with the relative offset to other acceleration structures with type VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR allocated with the same VkBuffer. That is, the difference in returned addresses between the two must be the same as the difference in offsets provided at acceleration structure creation.

The returned address must be aligned to 256 bytes.

Note

The acceleration structure device address may be different from the buffer device address corresponding to the acceleration structure’s start offset in its storage buffer for acceleration structure types other than VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR.
Valid Usage

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-accelerationStructure-08935
    The VkPhysicalDeviceAccelerationStructureFeaturesKHR::accelerationStructure feature must be enabled

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-device-03504
    If device was created with multiple physical devices, then the bufferDeviceAddressMultiDevice feature must be enabled

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-pInfo-09541
    If the buffer on which pInfo->accelerationStructure was placed is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-pInfo-09542
    The buffer on which pInfo->accelerationStructure was placed must have been created with the VK_BUFFER_USAGE_SHADER_DEVICE_ADDRESS_BIT usage flag

Valid Usage (Implicit)

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-device-parameter
    device must be a valid VkDevice handle

  • VUID-vkGetAccelerationStructureDeviceAddressKHR-pInfo-parameter
    pInfo must be a valid pointer to a valid VkAccelerationStructureDeviceAddressInfoKHR structure

See Also

VK_KHR_acceleration_structure, VkAccelerationStructureDeviceAddressInfoKHR, VkDevice

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 2014-2024 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0