# Vulkan® 1.4.304 - A Specification (with all registered extensions)

The Khronos® Vulkan Working Group
version 1.4.304, 2025-01-13 20:32:51Z
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## 37. Acceleration Structures

### 37.1. Acceleration Structures

Acceleration structures are data structures used by the implementation to efficiently manage scene geometry as it is traversed during a ray tracing query. The application is responsible for managing acceleration structure objects (see Acceleration Structures), including allocation, destruction, executing builds or updates, and synchronizing resources used during ray tracing queries.

There are two types of acceleration structures, top level acceleration structures and bottom level acceleration structures.

An acceleration structure is considered to be constructed if an acceleration structure build command or copy command has been executed with the given acceleration structure as the destination.

Figure 27. Acceleration Structure
Caption

The diagram shows the relationship between top and bottom level acceleration structures.

#### 37.1.1. Geometry

Geometries refer to a triangle or axis-aligned bounding box.

#### 37.1.2. Top Level Acceleration Structures

Opaque acceleration structure for an array of instances. The descriptor or device address referencing this is the starting point for traversal.

The top level acceleration structure takes a reference to any bottom level acceleration structure referenced by its instances. Those bottom level acceleration structure objects must be valid when the top level acceleration structure is accessed.

#### 37.1.3. Bottom Level Acceleration Structures

Opaque acceleration structure for an array of geometries.

#### 37.1.4. Acceleration Structure Update Rules

The API defines two types of operations to produce acceleration structures from geometry:

- A build operation is used to construct an acceleration structure.

- An update operation is used to modify an existing acceleration structure.

An update operation imposes certain constraints on the input, in exchange for considerably faster execution. When performing an update, the application is required to provide a full description of the acceleration structure, but is prohibited from changing anything other than instance definitions, transform matrices, and vertex or AABB positions. All other aspects of the description must exactly match the one from the original build.

More precisely, the application must not use an update operation to do any of the following:

- Change primitives or instances from active to inactive, or vice versa (as defined in Inactive Primitives and Instances).

- Change the index or vertex formats of triangle geometry.

- Change triangle geometry transform pointers from null to non-null or vice versa.

- Change the number of geometries or instances in the structure.

- Change the geometry flags for any geometry in the structure.

- Change the number of vertices or primitives for any geometry in the structure.

If the original acceleration structure was built using opacity micromaps and `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_OPACITY_MICROMAP_DATA_UPDATE_EXT` was set in `flags`, the application must provide the corresponding micromap information to the update operation. The application is prohibited from changing anything other than the specific opacity values assigned to the triangles.

More precisely, the application must not use an update operation to do any of the following:

- Remove micromaps or VkOpacityMicromapSpecialIndexEXT values from a geometry which previously had them, or vice versa.

- Change between use of VkOpacityMicromapSpecialIndexEXT values and explicit micro-map triangles.

- Change the subdivision level or format of the micromap triangle associated with any acceleration-structure triangle.

If the original acceleration structure was built using opacity micromaps and `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_OPACITY_MICROMAP_UPDATE_EXT` was set in `flags`, the application must provide a micromap to the update operation.

If the original acceleration structure was built using opacity micromaps and neither opacity micromap update flag is set the application must provide the original micromap to the update operation.

If the original acceleration structure was built using displacement micromaps and `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_DISPLACEMENT_MICROMAP_UPDATE_NV` was set in `flags`, the application must provide a displacement micromap to the update operation.

If the original acceleration structure was built using displacement micromaps and the displacement micromap update flag is not set the application must provide the original micromap to the update operation.

#### 37.1.5. Inactive Primitives and Instances

Acceleration structures allow the use of particular input values to signal inactive primitives or instances.

An inactive triangle is one for which the first (X) component of any vertex is NaN. If any other vertex component is NaN, and the first is not, the behavior is undefined. If the vertex format does not have a NaN representation, then all triangles are considered active.

An inactive instance is one whose acceleration structure reference is `0`.

An inactive AABB is one for which the minimum X coordinate is NaN. If any other component is NaN, and the first is not, the behavior is undefined.

In the above definitions, “NaN” refers to any type of NaN. Signaling, non-signaling, quiet, loud, or otherwise.

An inactive object is considered invisible to all rays, and should not be represented in the acceleration structure. Implementations should ensure that the presence of inactive objects does not seriously degrade traversal performance.

Inactive objects are counted in the auto-generated index sequences which are provided to shaders via `InstanceId` and `PrimitiveId` SPIR-V decorations. This allows objects in the scene to change freely between the active and inactive states, without affecting the layout of any arrays which are being indexed using the ID values.

Any transition between the active and inactive states requires a full acceleration structure rebuild. Applications must not perform an acceleration structure update where an object is active in the source acceleration structure but would be inactive in the destination, or vice versa.

#### 37.1.6. Degenerate Primitives and Instances

Degenerate primitives and instances behave differently to inactive primitives and instances, and are defined as:

- triangles that have one or more vertices whose respective (X), (Y), (Z) components are identical, or have three vertices that have at least two of the (X), (Y), or (Z) components identical, therefore forming a line or point. Degenerate triangles do not generate any intersections.

- AABBs whose `minX`=`maxX`, `minY`=`maxY`, and `minZ`=`maxZ`. Degenerate AABBs may invoke the intersection shader.

- instances that reference bottom level acceleration structures that contain no active primitives. When building an acceleration structure, implementations should treat degenerate instances as though they are a point at the instance origin, specified by VkAccelerationStructureInstanceKHR::`transform`.

Unlike inactive primitives and instances, degenerate primitives and instances may transition from the degenerate to the non-degenerate state, or vice versa, when performing an acceleration structure update.

If an acceleration structure is built without `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_UPDATE_BIT_KHR` set in VkAccelerationStructureInfoNV::`flags` or VkAccelerationStructureBuildGeometryInfoKHR::`flags` , degenerate primitives may be discarded. Primitives that are defined with the same index value for more than one vertex can always be discarded.

#### 37.1.7. Building Acceleration Structures

To build an acceleration structure call:

    // Provided by VK_NV_ray_tracing
    void vkCmdBuildAccelerationStructureNV(
        VkCommandBuffer                             commandBuffer,
        const VkAccelerationStructureInfoNV*        pInfo,
        VkBuffer                                    instanceData,
        VkDeviceSize                                instanceOffset,
        VkBool32                                    update,
        VkAccelerationStructureNV                   dst,
        VkAccelerationStructureNV                   src,
        VkBuffer                                    scratch,
        VkDeviceSize                                scratchOffset);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `pInfo` contains the shared information for the acceleration structure’s structure.

- `instanceData` is the buffer containing an array of VkAccelerationStructureInstanceKHR structures defining acceleration structures. This parameter must be `NULL` for bottom level acceleration structures.

- `instanceOffset` is the offset in bytes (relative to the start of `instanceData`) at which the instance data is located.

- `update` specifies whether to update the `dst` acceleration structure with the data in `src`.

- `dst` is a pointer to the target acceleration structure for the build.

- `src` is a pointer to an existing acceleration structure that is to be used to update the `dst` acceleration structure.

- `scratch` is the VkBuffer that will be used as scratch memory for the build.

- `scratchOffset` is the offset in bytes relative to the start of `scratch` that will be used as a scratch memory.

Accesses to `dst`, `src`, and `scratch` must be synchronized with the `VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of `VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR` or `VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR`.

Valid Usage

- VUID-vkCmdBuildAccelerationStructureNV-geometryCount-02241
  `geometryCount` must be less than or equal to VkPhysicalDeviceRayTracingPropertiesNV::`maxGeometryCount`

- VUID-vkCmdBuildAccelerationStructureNV-dst-02488
  `dst` must have been created with compatible VkAccelerationStructureInfoNV where VkAccelerationStructureInfoNV::`type` and VkAccelerationStructureInfoNV::`flags` are identical, VkAccelerationStructureInfoNV::`instanceCount` and VkAccelerationStructureInfoNV::`geometryCount` for `dst` are greater than or equal to the build size and each geometry in VkAccelerationStructureInfoNV::`pGeometries` for `dst` has greater than or equal to the number of vertices, indices, and AABBs

- VUID-vkCmdBuildAccelerationStructureNV-update-02489
  If `update` is `VK_TRUE`, `src` must not be VK_NULL_HANDLE

- VUID-vkCmdBuildAccelerationStructureNV-update-02490
  If `update` is `VK_TRUE`, `src` must have previously been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_UPDATE_BIT_NV` set in VkAccelerationStructureInfoNV::`flags` in the original build

- VUID-vkCmdBuildAccelerationStructureNV-update-02491
  If `update` is `VK_FALSE`, the `size` member of the VkMemoryRequirements structure returned from a call to vkGetAccelerationStructureMemoryRequirementsNV with VkAccelerationStructureMemoryRequirementsInfoNV::`accelerationStructure` set to `dst` and VkAccelerationStructureMemoryRequirementsInfoNV::`type` set to `VK_ACCELERATION_STRUCTURE_MEMORY_REQUIREMENTS_TYPE_BUILD_SCRATCH_NV` must be less than or equal to the size of `scratch` minus `scratchOffset`

- VUID-vkCmdBuildAccelerationStructureNV-update-02492
  If `update` is `VK_TRUE`, the `size` member of the VkMemoryRequirements structure returned from a call to vkGetAccelerationStructureMemoryRequirementsNV with VkAccelerationStructureMemoryRequirementsInfoNV::`accelerationStructure` set to `dst` and VkAccelerationStructureMemoryRequirementsInfoNV::`type` set to `VK_ACCELERATION_STRUCTURE_MEMORY_REQUIREMENTS_TYPE_UPDATE_SCRATCH_NV` must be less than or equal to the size of `scratch` minus `scratchOffset`

- VUID-vkCmdBuildAccelerationStructureNV-scratch-03522
  `scratch` must have been created with `VK_BUFFER_USAGE_RAY_TRACING_BIT_NV` usage flag

- VUID-vkCmdBuildAccelerationStructureNV-instanceData-03523
  If `instanceData` is not VK_NULL_HANDLE, `instanceData` must have been created with `VK_BUFFER_USAGE_RAY_TRACING_BIT_NV` usage flag

- VUID-vkCmdBuildAccelerationStructureNV-accelerationStructureReference-03786
  Each VkAccelerationStructureInstanceKHR::`accelerationStructureReference` value in `instanceData` must be a valid device address containing a value obtained from vkGetAccelerationStructureHandleNV

- VUID-vkCmdBuildAccelerationStructureNV-update-03524
  If `update` is `VK_TRUE`, then objects that were previously active must not be made inactive as per Inactive Primitives and Instances

- VUID-vkCmdBuildAccelerationStructureNV-update-03525
  If `update` is `VK_TRUE`, then objects that were previously inactive must not be made active as per Inactive Primitives and Instances

- VUID-vkCmdBuildAccelerationStructureNV-update-03526
  If `update` is `VK_TRUE`, the `src` and `dst` objects must either be the same object or not have any memory aliasing

- VUID-vkCmdBuildAccelerationStructureNV-dst-07787
  `dst` must be bound completely and contiguously to a single `VkDeviceMemory` object via vkBindAccelerationStructureMemoryNV

Valid Usage (Implicit)

- VUID-vkCmdBuildAccelerationStructureNV-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdBuildAccelerationStructureNV-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkAccelerationStructureInfoNV structure

- VUID-vkCmdBuildAccelerationStructureNV-instanceData-parameter
  If `instanceData` is not VK_NULL_HANDLE, `instanceData` must be a valid VkBuffer handle

- VUID-vkCmdBuildAccelerationStructureNV-dst-parameter
  `dst` must be a valid VkAccelerationStructureNV handle

- VUID-vkCmdBuildAccelerationStructureNV-src-parameter
  If `src` is not VK_NULL_HANDLE, `src` must be a valid VkAccelerationStructureNV handle

- VUID-vkCmdBuildAccelerationStructureNV-scratch-parameter
  `scratch` must be a valid VkBuffer handle

- VUID-vkCmdBuildAccelerationStructureNV-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdBuildAccelerationStructureNV-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdBuildAccelerationStructureNV-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdBuildAccelerationStructureNV-videocoding
  This command must only be called outside of a video coding scope

- VUID-vkCmdBuildAccelerationStructureNV-commonparent
  Each of `commandBuffer`, `dst`, `instanceData`, `scratch`, and `src` 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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

To build acceleration structures call:

    // Provided by VK_KHR_acceleration_structure
    void vkCmdBuildAccelerationStructuresKHR(
        VkCommandBuffer                             commandBuffer,
        uint32_t                                    infoCount,
        const VkAccelerationStructureBuildGeometryInfoKHR* pInfos,
        const VkAccelerationStructureBuildRangeInfoKHR* const* ppBuildRangeInfos);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `infoCount` is the number of acceleration structures to build. It specifies the number of the `pInfos` structures and `ppBuildRangeInfos` pointers that must be provided.

- `pInfos` is a pointer to an array of `infoCount` VkAccelerationStructureBuildGeometryInfoKHR structures defining the geometry used to build each acceleration structure.

- `ppBuildRangeInfos` is a pointer to an array of `infoCount` pointers to arrays of VkAccelerationStructureBuildRangeInfoKHR structures. Each `ppBuildRangeInfos`[i] is a pointer to an array of `pInfos`[i].`geometryCount` VkAccelerationStructureBuildRangeInfoKHR structures defining dynamic offsets to the addresses where geometry data is stored, as defined by `pInfos`[i].

The `vkCmdBuildAccelerationStructuresKHR` command provides the ability to initiate multiple acceleration structures builds, however there is no ordering or synchronization implied between any of the individual acceleration structure builds.

Note | This means that an application cannot build a top-level acceleration structure in the same vkCmdBuildAccelerationStructuresKHR call as the associated bottom-level or instance acceleration structures are being built. There also cannot be any memory aliasing between any acceleration structure memories or scratch memories being used by any of the builds.

Accesses to the acceleration structure scratch buffers as identified by the VkAccelerationStructureBuildGeometryInfoKHR::`scratchData` buffer device addresses must be synchronized with the `VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of (`VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR` | `VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR`). Accesses to each VkAccelerationStructureBuildGeometryInfoKHR::`srcAccelerationStructure` and VkAccelerationStructureBuildGeometryInfoKHR::`dstAccelerationStructure` must be synchronized with the `VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of `VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR` or `VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR`, as appropriate.

Accesses to other input buffers as identified by any used values of VkAccelerationStructureGeometryMotionTrianglesDataNV::`vertexData`, VkAccelerationStructureGeometryTrianglesDataKHR::`vertexData`, VkAccelerationStructureGeometryTrianglesDataKHR::`indexData`, VkAccelerationStructureGeometryTrianglesDataKHR::`transformData`, VkAccelerationStructureGeometryAabbsDataKHR::`data`, and VkAccelerationStructureGeometryInstancesDataKHR::`data` must be synchronized with the `VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of `VK_ACCESS_SHADER_READ_BIT`.

Valid Usage

- VUID-vkCmdBuildAccelerationStructuresKHR-accelerationStructure-08923
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

- VUID-vkCmdBuildAccelerationStructuresKHR-mode-04628
  The `mode` member of each element of `pInfos` must be a valid VkBuildAccelerationStructureModeKHR value

- VUID-vkCmdBuildAccelerationStructuresKHR-srcAccelerationStructure-04629
  If the `srcAccelerationStructure` member of any element of `pInfos` is not VK_NULL_HANDLE, the `srcAccelerationStructure` member must be a valid VkAccelerationStructureKHR handle

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-04630
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must not be VK_NULL_HANDLE

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03403
  The `srcAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03698
  The `dstAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03800
  The `dstAccelerationStructure` member of any element of `pInfos` must be a valid VkAccelerationStructureKHR handle

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03699
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03700
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03663
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, inactive primitives in its `srcAccelerationStructure` member must not be made active

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03664
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, active primitives in its `srcAccelerationStructure` member must not be made inactive

- VUID-vkCmdBuildAccelerationStructuresKHR-None-03407
  The `dstAccelerationStructure` member of any element of `pInfos` must not be referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03701
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any other element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03702
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `dstAccelerationStructure` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03703
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any element of `pInfos` (including the same element), which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-scratchData-03704
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-scratchData-03705
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` (including the same element), which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-dstAccelerationStructure-03706
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing any acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03667
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must have previously been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_UPDATE_BIT_KHR` set in VkAccelerationStructureBuildGeometryInfoKHR::`flags` in the build

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03668
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` and `dstAccelerationStructure` members must either be the same VkAccelerationStructureKHR, or not have any memory aliasing

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03758
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `geometryCount` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03759
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03760
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `type` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03761
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `geometryType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03762
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03763
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.vertexFormat` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03764
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.maxVertex` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03765
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.indexType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03766
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was `NULL` when `srcAccelerationStructure` was last built, then it must be `NULL`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03767
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was not `NULL` when `srcAccelerationStructure` was last built, then it must not be `NULL`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03768
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, and `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, then the value of each index referenced must be the same as the corresponding index value when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-primitiveCount-03769
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, the `primitiveCount` member of its corresponding `VkAccelerationStructureBuildRangeInfoKHR` structure must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03801
  For each element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, the corresponding `ppBuildRangeInfos`[i][j].`primitiveCount` must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxInstanceCount`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03707
  For each element of `pInfos`, the `buffer` used to create its `dstAccelerationStructure` member must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03708
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` the `buffer` used to create its `srcAccelerationStructure` member must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03709
  For each element of `pInfos`, the `buffer` used to create each acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03671
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_BUILD_KHR`, all addresses between `pInfos`[i].`scratchData.deviceAddress` and `pInfos`[i].`scratchData.deviceAddress` + N - 1 must be in the buffer device address range of the same buffer, where N is given by the `buildScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03672
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, all addresses between `pInfos`[i].`scratchData.deviceAddress` and `pInfos`[i].`scratchData.deviceAddress` + N - 1 must be in the buffer device address range of the same buffer, where N is given by the `updateScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkCmdBuildAccelerationStructuresKHR-geometry-03673
  The buffers from which the buffer device addresses for all of the `geometry.triangles.vertexData`, `geometry.triangles.indexData`, `geometry.triangles.transformData`, `geometry.aabbs.data`, and `geometry.instances.data` members of all `pInfos`[i].`pGeometries` and `pInfos`[i].`ppGeometries` are queried must have been created with the `VK_BUFFER_USAGE_ACCELERATION_STRUCTURE_BUILD_INPUT_READ_ONLY_BIT_KHR` usage flag

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03674
  The buffer from which the buffer device address `pInfos`[i].`scratchData.deviceAddress` is queried must have been created with `VK_BUFFER_USAGE_STORAGE_BUFFER_BIT` usage flag

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03802
  For each element of `pInfos`, its `scratchData.deviceAddress` member must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03803
  For each element of `pInfos`, if `scratchData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03710
  For each element of `pInfos`, its `scratchData.deviceAddress` member must be a multiple of VkPhysicalDeviceAccelerationStructurePropertiesKHR::`minAccelerationStructureScratchOffsetAlignment`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03804
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `geometry.triangles.vertexData.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03805
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.vertexData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03711
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `geometry.triangles.vertexData.deviceAddress` must be aligned to the size in bytes of the smallest component of the format in `vertexFormat`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03806
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, `geometry.triangles.indexData.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03807
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, if `geometry.triangles.indexData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03712
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, and with `geometry.triangles.indexType` not equal to `VK_INDEX_TYPE_NONE_KHR`, `geometry.triangles.indexData.deviceAddress` must be aligned to the size in bytes of the type in `indexType`

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03808
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is not `0`, it must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03809
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03810
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is not `0`, it must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03811
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, `geometry.aabbs.data.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03812
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, if `geometry.aabbs.data.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03714
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, `geometry.aabbs.data.deviceAddress` must be aligned to `8` bytes

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03715
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_FALSE`, `geometry.instances.data.deviceAddress` must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03716
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_TRUE`, `geometry.instances.data.deviceAddress` must be aligned to `8` bytes

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03717
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_TRUE`, each element of `geometry.instances.data.deviceAddress` in device memory must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03813
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, `geometry.instances.data.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-03814
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.instances.data.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-06707
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, each VkAccelerationStructureInstanceKHR::`accelerationStructureReference` value in `geometry.instances.data.deviceAddress` must be a valid device address containing a value obtained from vkGetAccelerationStructureDeviceAddressKHR or `0`

- VUID-vkCmdBuildAccelerationStructuresKHR-commandBuffer-09547
  `commandBuffer` must not be a protected command buffer

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-10126
  For each `pInfos`[i], `dstAccelerationStructure` must have been created with a value of VkAccelerationStructureCreateInfoKHR::`size` greater than or equal to either:

  - the memory size required by the build operation, as returned by vkGetAccelerationStructureBuildSizesKHR with `pBuildInfo` = `pInfos`[i] and with each element of the `pMaxPrimitiveCounts` array greater than or equal to the equivalent `ppBuildRangeInfos`[i][j].`primitiveCount` values for `j` in [0,`pInfos`[i].`geometryCount`) or,

  - the result of querying the corresponding `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR`, if updating a compacted acceleration structure

- VUID-vkCmdBuildAccelerationStructuresKHR-ppBuildRangeInfos-03676
  Each element of `ppBuildRangeInfos`[i] must be a valid pointer to an array of `pInfos`[i].`geometryCount` `VkAccelerationStructureBuildRangeInfoKHR` structures

Valid Usage (Implicit)

- VUID-vkCmdBuildAccelerationStructuresKHR-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdBuildAccelerationStructuresKHR-pInfos-parameter
  `pInfos` must be a valid pointer to an array of `infoCount` valid VkAccelerationStructureBuildGeometryInfoKHR structures

- VUID-vkCmdBuildAccelerationStructuresKHR-ppBuildRangeInfos-parameter
  `ppBuildRangeInfos` must be a valid pointer to an array of `infoCount` VkAccelerationStructureBuildRangeInfoKHR structures

- VUID-vkCmdBuildAccelerationStructuresKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdBuildAccelerationStructuresKHR-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdBuildAccelerationStructuresKHR-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdBuildAccelerationStructuresKHR-videocoding
  This command must only be called outside of a video coding scope

- VUID-vkCmdBuildAccelerationStructuresKHR-infoCount-arraylength
  `infoCount` must be greater than `0`

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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

To build acceleration structures with some parameters sourced on the device call:

    // Provided by VK_KHR_acceleration_structure
    void vkCmdBuildAccelerationStructuresIndirectKHR(
        VkCommandBuffer                             commandBuffer,
        uint32_t                                    infoCount,
        const VkAccelerationStructureBuildGeometryInfoKHR* pInfos,
        const VkDeviceAddress*                      pIndirectDeviceAddresses,
        const uint32_t*                             pIndirectStrides,
        const uint32_t* const*                      ppMaxPrimitiveCounts);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `infoCount` is the number of acceleration structures to build.

- `pInfos` is a pointer to an array of `infoCount` VkAccelerationStructureBuildGeometryInfoKHR structures defining the geometry used to build each acceleration structure.

- `pIndirectDeviceAddresses` is a pointer to an array of `infoCount` buffer device addresses which point to `pInfos`[i].`geometryCount` VkAccelerationStructureBuildRangeInfoKHR structures defining dynamic offsets to the addresses where geometry data is stored, as defined by `pInfos`[i].

- `pIndirectStrides` is a pointer to an array of `infoCount` byte strides between elements of `pIndirectDeviceAddresses`.

- `ppMaxPrimitiveCounts` is a pointer to an array of `infoCount` pointers to arrays of `pInfos`[i].`geometryCount` values indicating the maximum number of primitives that will be built by this command for each geometry.

Accesses to acceleration structures, scratch buffers, vertex buffers, index buffers, and instance buffers must be synchronized as with vkCmdBuildAccelerationStructuresKHR.

Accesses to any element of `pIndirectDeviceAddresses` must be synchronized with the `VK_PIPELINE_STAGE_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of `VK_ACCESS_INDIRECT_COMMAND_READ_BIT`.

Valid Usage

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-accelerationStructureIndirectBuild-03650
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureIndirectBuild` feature must be enabled

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-mode-04628
  The `mode` member of each element of `pInfos` must be a valid VkBuildAccelerationStructureModeKHR value

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-srcAccelerationStructure-04629
  If the `srcAccelerationStructure` member of any element of `pInfos` is not VK_NULL_HANDLE, the `srcAccelerationStructure` member must be a valid VkAccelerationStructureKHR handle

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-04630
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must not be VK_NULL_HANDLE

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03403
  The `srcAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03698
  The `dstAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03800
  The `dstAccelerationStructure` member of any element of `pInfos` must be a valid VkAccelerationStructureKHR handle

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03699
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03700
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03663
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, inactive primitives in its `srcAccelerationStructure` member must not be made active

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03664
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, active primitives in its `srcAccelerationStructure` member must not be made inactive

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-None-03407
  The `dstAccelerationStructure` member of any element of `pInfos` must not be referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03701
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any other element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03702
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `dstAccelerationStructure` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03703
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any element of `pInfos` (including the same element), which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-scratchData-03704
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-scratchData-03705
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` (including the same element), which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-dstAccelerationStructure-03706
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing any acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`, which is accessed by this command

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03667
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must have previously been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_UPDATE_BIT_KHR` set in VkAccelerationStructureBuildGeometryInfoKHR::`flags` in the build

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03668
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` and `dstAccelerationStructure` members must either be the same VkAccelerationStructureKHR, or not have any memory aliasing

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03758
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `geometryCount` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03759
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03760
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `type` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03761
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `geometryType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03762
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03763
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.vertexFormat` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03764
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.maxVertex` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03765
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.indexType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03766
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was `NULL` when `srcAccelerationStructure` was last built, then it must be `NULL`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03767
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was not `NULL` when `srcAccelerationStructure` was last built, then it must not be `NULL`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03768
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, and `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, then the value of each index referenced must be the same as the corresponding index value when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-primitiveCount-03769
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, the `primitiveCount` member of its corresponding `VkAccelerationStructureBuildRangeInfoKHR` structure must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03801
  For each element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, the corresponding `ppMaxPrimitiveCounts`[i][j] must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxInstanceCount`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03707
  For each element of `pInfos`, the `buffer` used to create its `dstAccelerationStructure` member must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03708
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` the `buffer` used to create its `srcAccelerationStructure` member must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03709
  For each element of `pInfos`, the `buffer` used to create each acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` must be bound to device memory

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03671
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_BUILD_KHR`, all addresses between `pInfos`[i].`scratchData.deviceAddress` and `pInfos`[i].`scratchData.deviceAddress` + N - 1 must be in the buffer device address range of the same buffer, where N is given by the `buildScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03672
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, all addresses between `pInfos`[i].`scratchData.deviceAddress` and `pInfos`[i].`scratchData.deviceAddress` + N - 1 must be in the buffer device address range of the same buffer, where N is given by the `updateScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-geometry-03673
  The buffers from which the buffer device addresses for all of the `geometry.triangles.vertexData`, `geometry.triangles.indexData`, `geometry.triangles.transformData`, `geometry.aabbs.data`, and `geometry.instances.data` members of all `pInfos`[i].`pGeometries` and `pInfos`[i].`ppGeometries` are queried must have been created with the `VK_BUFFER_USAGE_ACCELERATION_STRUCTURE_BUILD_INPUT_READ_ONLY_BIT_KHR` usage flag

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03674
  The buffer from which the buffer device address `pInfos`[i].`scratchData.deviceAddress` is queried must have been created with `VK_BUFFER_USAGE_STORAGE_BUFFER_BIT` usage flag

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03802
  For each element of `pInfos`, its `scratchData.deviceAddress` member must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03803
  For each element of `pInfos`, if `scratchData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03710
  For each element of `pInfos`, its `scratchData.deviceAddress` member must be a multiple of VkPhysicalDeviceAccelerationStructurePropertiesKHR::`minAccelerationStructureScratchOffsetAlignment`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03804
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `geometry.triangles.vertexData.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03805
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.vertexData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03711
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `geometry.triangles.vertexData.deviceAddress` must be aligned to the size in bytes of the smallest component of the format in `vertexFormat`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03806
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, `geometry.triangles.indexData.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03807
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, if `geometry.triangles.indexData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03712
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, and with `geometry.triangles.indexType` not equal to `VK_INDEX_TYPE_NONE_KHR`, `geometry.triangles.indexData.deviceAddress` must be aligned to the size in bytes of the type in `indexType`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03808
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is not `0`, it must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03809
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03810
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.deviceAddress` is not `0`, it must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03811
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, `geometry.aabbs.data.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03812
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, if `geometry.aabbs.data.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03714
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, `geometry.aabbs.data.deviceAddress` must be aligned to `8` bytes

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03715
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_FALSE`, `geometry.instances.data.deviceAddress` must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03716
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_TRUE`, `geometry.instances.data.deviceAddress` must be aligned to `8` bytes

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03717
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.arrayOfPointers` is `VK_TRUE`, each element of `geometry.instances.data.deviceAddress` in device memory must be aligned to `16` bytes

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03813
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, `geometry.instances.data.deviceAddress` must be a valid device address obtained from vkGetBufferDeviceAddress

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03814
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, if `geometry.instances.data.deviceAddress` is the address of a non-sparse buffer then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-06707
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, each VkAccelerationStructureInstanceKHR::`accelerationStructureReference` value in `geometry.instances.data.deviceAddress` must be a valid device address containing a value obtained from vkGetAccelerationStructureDeviceAddressKHR or `0`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-commandBuffer-09547
  `commandBuffer` must not be a protected command buffer

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-03645
  For any element of `pIndirectDeviceAddresses`, if the buffer from which it was queried is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-03646
  For any element of `pIndirectDeviceAddresses`[i], all device addresses between `pIndirectDeviceAddresses`[i] and `pIndirectDeviceAddresses`[i] + (`pInfos`[i].`geometryCount` × `pIndirectStrides`[i]) - 1 must be in the buffer device address range of the same buffer

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-03647
  For any element of `pIndirectDeviceAddresses`, the buffer from which it was queried must have been created with the `VK_BUFFER_USAGE_INDIRECT_BUFFER_BIT` bit set

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-03648
  Each element of `pIndirectDeviceAddresses` must be a multiple of `4`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectStrides-03787
  Each element of `pIndirectStrides` must be a multiple of `4`

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-03651
  Each VkAccelerationStructureBuildRangeInfoKHR structure referenced by any element of `pIndirectDeviceAddresses` must be a valid VkAccelerationStructureBuildRangeInfoKHR structure

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-03652
  `pInfos`[i].`dstAccelerationStructure` must have been created with a value of VkAccelerationStructureCreateInfoKHR::`size` greater than or equal to the memory size required by the build operation, as returned by vkGetAccelerationStructureBuildSizesKHR with `pBuildInfo` = `pInfos`[i] and `pMaxPrimitiveCounts` = `ppMaxPrimitiveCounts`[i]

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-ppMaxPrimitiveCounts-03653
  Each `ppMaxPrimitiveCounts`[i][j] must be greater than or equal to the `primitiveCount` value specified by the VkAccelerationStructureBuildRangeInfoKHR structure located at `pIndirectDeviceAddresses`[i] + (`j` × `pIndirectStrides`[i])

Valid Usage (Implicit)

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pInfos-parameter
  `pInfos` must be a valid pointer to an array of `infoCount` valid VkAccelerationStructureBuildGeometryInfoKHR structures

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectDeviceAddresses-parameter
  `pIndirectDeviceAddresses` must be a valid pointer to an array of `infoCount` VkDeviceAddress values

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-pIndirectStrides-parameter
  `pIndirectStrides` must be a valid pointer to an array of `infoCount` `uint32_t` values

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-ppMaxPrimitiveCounts-parameter
  `ppMaxPrimitiveCounts` must be a valid pointer to an array of `infoCount` `uint32_t` values

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-videocoding
  This command must only be called outside of a video coding scope

- VUID-vkCmdBuildAccelerationStructuresIndirectKHR-infoCount-arraylength
  `infoCount` must be greater than `0`

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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

The `VkAccelerationStructureBuildGeometryInfoKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureBuildGeometryInfoKHR {
        VkStructureType                                     sType;
        const void*                                         pNext;
        VkAccelerationStructureTypeKHR                      type;
        VkBuildAccelerationStructureFlagsKHR                flags;
        VkBuildAccelerationStructureModeKHR                 mode;
        VkAccelerationStructureKHR                          srcAccelerationStructure;
        VkAccelerationStructureKHR                          dstAccelerationStructure;
        uint32_t                                            geometryCount;
        const VkAccelerationStructureGeometryKHR*           pGeometries;
        const VkAccelerationStructureGeometryKHR* const*    ppGeometries;
        VkDeviceOrHostAddressKHR                            scratchData;
    } VkAccelerationStructureBuildGeometryInfoKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `type` is a VkAccelerationStructureTypeKHR value specifying the type of acceleration structure being built.

- `flags` is a bitmask of VkBuildAccelerationStructureFlagBitsKHR specifying additional parameters of the acceleration structure.

- `mode` is a VkBuildAccelerationStructureModeKHR value specifying the type of operation to perform.

- `srcAccelerationStructure` is a pointer to an existing acceleration structure that is to be used to update the `dstAccelerationStructure` acceleration structure when `mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`.

- `dstAccelerationStructure` is a pointer to the target acceleration structure for the build.

- `geometryCount` specifies the number of geometries that will be built into `dstAccelerationStructure`.

- `pGeometries` is a pointer to an array of VkAccelerationStructureGeometryKHR structures.

- `ppGeometries` is a pointer to an array of pointers to VkAccelerationStructureGeometryKHR structures.

- `scratchData` is the device or host address to memory that will be used as scratch memory for the build.

Only one of `pGeometries` or `ppGeometries` can be a valid pointer, the other must be `NULL`. Each element of the non-`NULL` array describes the data used to build each acceleration structure geometry.

The index of each element of the `pGeometries` or `ppGeometries` members of VkAccelerationStructureBuildGeometryInfoKHR is used as the geometry index during ray traversal. The geometry index is available in ray shaders via the `RayGeometryIndexKHR` built-in, and is used to determine hit and intersection shaders executed during traversal. The geometry index is available to ray queries via the `OpRayQueryGetIntersectionGeometryIndexKHR` instruction.

Setting `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` in `flags` indicates that this build is a motion top level acceleration structure. A motion top level uses instances of format VkAccelerationStructureMotionInstanceNV if VkAccelerationStructureGeometryInstancesDataKHR::`arrayOfPointers` is `VK_FALSE`.

If VkAccelerationStructureGeometryInstancesDataKHR::`arrayOfPointers` is `VK_TRUE`, the pointer for each element of the array of instance pointers consists of 4 bits of `VkAccelerationStructureMotionInstanceTypeNV` in the low 4 bits of the pointer identifying the type of structure at the pointer. The device address accessed is the value in the array with the low 4 bits set to zero. The structure at the pointer is one of VkAccelerationStructureInstanceKHR, VkAccelerationStructureMatrixMotionInstanceNV or VkAccelerationStructureSRTMotionInstanceNV, depending on the type value encoded in the low 4 bits.

A top level acceleration structure with either motion instances or vertex motion in its instances must set `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` in `flags`.

Members `srcAccelerationStructure` and `dstAccelerationStructure` may be the same or different for an update operation (when `mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`). If they are the same, the update happens in-place. Otherwise, the target acceleration structure is updated and the source is not modified.

Valid Usage

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03654
  `type` must not be `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-pGeometries-03788
  If `geometryCount` is not `0`, exactly one of `pGeometries` or `ppGeometries` must be a valid pointer, the other must be `NULL`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03789
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR`, the `geometryType` member of elements of either `pGeometries` or `ppGeometries` must be `VK_GEOMETRY_TYPE_INSTANCES_KHR`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03790
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR`, `geometryCount` must be `1`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03791
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` the `geometryType` member of elements of either `pGeometries` or `ppGeometries` must not be `VK_GEOMETRY_TYPE_INSTANCES_KHR`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03792
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` then the `geometryType` member of each geometry in either `pGeometries` or `ppGeometries` must be the same

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03793
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` then `geometryCount` must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxGeometryCount`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03794
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` and the `geometryType` member of either `pGeometries` or `ppGeometries` is `VK_GEOMETRY_TYPE_AABBS_KHR`, the total number of AABBs in all geometries must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxPrimitiveCount`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-03795
  If `type` is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` and the `geometryType` member of either `pGeometries` or `ppGeometries` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, the total number of triangles in all geometries must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxPrimitiveCount`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-flags-03796
  If `flags` has the `VK_BUILD_ACCELERATION_STRUCTURE_PREFER_FAST_TRACE_BIT_KHR` bit set, then it must not have the `VK_BUILD_ACCELERATION_STRUCTURE_PREFER_FAST_BUILD_BIT_KHR` bit set

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-dstAccelerationStructure-04927
  If `dstAccelerationStructure` was created with `VK_ACCELERATION_STRUCTURE_CREATE_MOTION_BIT_NV` set in VkAccelerationStructureCreateInfoKHR::`flags`, `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` must be set in `flags`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-flags-04928
  If `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` is set in `flags`, `dstAccelerationStructure` must have been created with `VK_ACCELERATION_STRUCTURE_CREATE_MOTION_BIT_NV` set in VkAccelerationStructureCreateInfoKHR::`flags`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-flags-04929
  If `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` is set in `flags`, `type` must not be `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-flags-07334
  If `flags` has the `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_OPACITY_MICROMAP_UPDATE_EXT` bit set then it must not have the `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_OPACITY_MICROMAP_DATA_UPDATE_EXT` bit set

Valid Usage (Implicit)

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_BUILD_GEOMETRY_INFO_KHR`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-type-parameter
  `type` must be a valid VkAccelerationStructureTypeKHR value

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-flags-parameter
  `flags` must be a valid combination of VkBuildAccelerationStructureFlagBitsKHR values

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-pGeometries-parameter
  If `geometryCount` is not `0`, and `pGeometries` is not `NULL`, `pGeometries` must be a valid pointer to an array of `geometryCount` valid VkAccelerationStructureGeometryKHR structures

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-ppGeometries-parameter
  If `geometryCount` is not `0`, and `ppGeometries` is not `NULL`, `ppGeometries` must be a valid pointer to an array of `geometryCount` valid pointers to valid VkAccelerationStructureGeometryKHR structures

- VUID-VkAccelerationStructureBuildGeometryInfoKHR-commonparent
  Both of `dstAccelerationStructure`, and `srcAccelerationStructure` that are valid handles of non-ignored parameters must have been created, allocated, or retrieved from the same VkDevice

The `VkBuildAccelerationStructureModeKHR` enumeration is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef enum VkBuildAccelerationStructureModeKHR {
        VK_BUILD_ACCELERATION_STRUCTURE_MODE_BUILD_KHR = 0,
        VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR = 1,
    } VkBuildAccelerationStructureModeKHR;

- `VK_BUILD_ACCELERATION_STRUCTURE_MODE_BUILD_KHR` specifies that the destination acceleration structure will be built using the specified geometries.

- `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` specifies that the destination acceleration structure will be built using data in a source acceleration structure, updated by the specified geometries.

The `VkDeviceOrHostAddressKHR` union is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef union VkDeviceOrHostAddressKHR {
        VkDeviceAddress    deviceAddress;
        void*              hostAddress;
    } VkDeviceOrHostAddressKHR;

- `deviceAddress` is a buffer device address as returned by the vkGetBufferDeviceAddressKHR command.

- `hostAddress` is a host memory address.

The `VkDeviceOrHostAddressConstKHR` union is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef union VkDeviceOrHostAddressConstKHR {
        VkDeviceAddress    deviceAddress;
        const void*        hostAddress;
    } VkDeviceOrHostAddressConstKHR;

- `deviceAddress` is a buffer device address as returned by the vkGetBufferDeviceAddressKHR command.

- `hostAddress` is a const host memory address.

The `VkAccelerationStructureGeometryKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureGeometryKHR {
        VkStructureType                           sType;
        const void*                               pNext;
        VkGeometryTypeKHR                         geometryType;
        VkAccelerationStructureGeometryDataKHR    geometry;
        VkGeometryFlagsKHR                        flags;
    } VkAccelerationStructureGeometryKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `geometryType` describes which type of geometry this `VkAccelerationStructureGeometryKHR` refers to.

- `geometry` is a VkAccelerationStructureGeometryDataKHR union describing the geometry data for the relevant geometry type.

- `flags` is a bitmask of VkGeometryFlagBitsKHR values describing additional properties of how the geometry should be built.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureGeometryKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_KHR`

- VUID-VkAccelerationStructureGeometryKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkAccelerationStructureGeometryKHR-geometryType-parameter
  `geometryType` must be a valid VkGeometryTypeKHR value

- VUID-VkAccelerationStructureGeometryKHR-triangles-parameter
  If `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, the `triangles` member of `geometry` must be a valid VkAccelerationStructureGeometryTrianglesDataKHR structure

- VUID-VkAccelerationStructureGeometryKHR-aabbs-parameter
  If `geometryType` is `VK_GEOMETRY_TYPE_AABBS_KHR`, the `aabbs` member of `geometry` must be a valid VkAccelerationStructureGeometryAabbsDataKHR structure

- VUID-VkAccelerationStructureGeometryKHR-instances-parameter
  If `geometryType` is `VK_GEOMETRY_TYPE_INSTANCES_KHR`, the `instances` member of `geometry` must be a valid VkAccelerationStructureGeometryInstancesDataKHR structure

- VUID-VkAccelerationStructureGeometryKHR-flags-parameter
  `flags` must be a valid combination of VkGeometryFlagBitsKHR values

The `VkAccelerationStructureGeometryDataKHR` union is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef union VkAccelerationStructureGeometryDataKHR {
        VkAccelerationStructureGeometryTrianglesDataKHR    triangles;
        VkAccelerationStructureGeometryAabbsDataKHR        aabbs;
        VkAccelerationStructureGeometryInstancesDataKHR    instances;
    } VkAccelerationStructureGeometryDataKHR;

- `triangles` is a VkAccelerationStructureGeometryTrianglesDataKHR structure.

- `aabbs` is a VkAccelerationStructureGeometryAabbsDataKHR structure.

- `instances` is a VkAccelerationStructureGeometryInstancesDataKHR structure.

The `VkAccelerationStructureGeometryTrianglesDataKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureGeometryTrianglesDataKHR {
        VkStructureType                  sType;
        const void*                      pNext;
        VkFormat                         vertexFormat;
        VkDeviceOrHostAddressConstKHR    vertexData;
        VkDeviceSize                     vertexStride;
        uint32_t                         maxVertex;
        VkIndexType                      indexType;
        VkDeviceOrHostAddressConstKHR    indexData;
        VkDeviceOrHostAddressConstKHR    transformData;
    } VkAccelerationStructureGeometryTrianglesDataKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `vertexFormat` is the VkFormat of each vertex element.

- `vertexData` is a device or host address to memory containing vertex data for this geometry.

- `maxVertex` is the number of vertices in `vertexData` minus one.

- `vertexStride` is the stride in bytes between each vertex.

- `indexType` is the VkIndexType of each index element.

- `indexData` is a device or host address to memory containing index data for this geometry.

- `transformData` is a device or host address to memory containing an optional reference to a VkTransformMatrixKHR structure describing a transformation from the space in which the vertices in this geometry are described to the space in which the acceleration structure is defined.

Note | Unlike the stride for vertex buffers in VkVertexInputBindingDescription for graphics pipelines which must not exceed `maxVertexInputBindingStride`, `vertexStride` for acceleration structure geometry is instead restricted to being a 32-bit value.

Valid Usage

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-vertexStride-03735
  `vertexStride` must be a multiple of the size in bytes of the smallest component of `vertexFormat`

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-vertexStride-03819
  `vertexStride` must be less than or equal to 232-1

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-vertexFormat-03797
  The format features of `vertexFormat` must contain `VK_FORMAT_FEATURE_ACCELERATION_STRUCTURE_VERTEX_BUFFER_BIT_KHR`

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-indexType-03798
  `indexType` must be `VK_INDEX_TYPE_UINT16`, `VK_INDEX_TYPE_UINT32`, or `VK_INDEX_TYPE_NONE_KHR`

Valid Usage (Implicit)

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_TRIANGLES_DATA_KHR`

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-pNext-pNext
  Each `pNext` member of any structure (including this one) in the `pNext` chain must be either `NULL` or a pointer to a valid instance of VkAccelerationStructureGeometryMotionTrianglesDataNV, VkAccelerationStructureTrianglesDisplacementMicromapNV, or VkAccelerationStructureTrianglesOpacityMicromapEXT

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-sType-unique
  The `sType` value of each struct in the `pNext` chain must be unique

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-vertexFormat-parameter
  `vertexFormat` must be a valid VkFormat value

- VUID-VkAccelerationStructureGeometryTrianglesDataKHR-indexType-parameter
  `indexType` must be a valid VkIndexType value

The `VkAccelerationStructureGeometryMotionTrianglesDataNV` structure is defined as:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef struct VkAccelerationStructureGeometryMotionTrianglesDataNV {
        VkStructureType                  sType;
        const void*                      pNext;
        VkDeviceOrHostAddressConstKHR    vertexData;
    } VkAccelerationStructureGeometryMotionTrianglesDataNV;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `vertexData` is a pointer to vertex data for this geometry at time 1.0

If `VkAccelerationStructureGeometryMotionTrianglesDataNV` is included in the `pNext` chain of a VkAccelerationStructureGeometryTrianglesDataKHR structure, the basic vertex positions are used for the position of the triangles in the geometry at time 0.0 and the `vertexData` in `VkAccelerationStructureGeometryMotionTrianglesDataNV` is used for the vertex positions at time 1.0, with positions linearly interpolated at intermediate times.

Indexing for `VkAccelerationStructureGeometryMotionTrianglesDataNV` `vertexData` is equivalent to the basic vertex position data.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureGeometryMotionTrianglesDataNV-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_MOTION_TRIANGLES_DATA_NV`

The `VkAccelerationStructureTrianglesOpacityMicromapEXT` structure is defined as:

    // Provided by VK_EXT_opacity_micromap
    typedef struct VkAccelerationStructureTrianglesOpacityMicromapEXT {
        VkStructureType                     sType;
        void*                               pNext;
        VkIndexType                         indexType;
        VkDeviceOrHostAddressConstKHR       indexBuffer;
        VkDeviceSize                        indexStride;
        uint32_t                            baseTriangle;
        uint32_t                            usageCountsCount;
        const VkMicromapUsageEXT*           pUsageCounts;
        const VkMicromapUsageEXT* const*    ppUsageCounts;
        VkMicromapEXT                       micromap;
    } VkAccelerationStructureTrianglesOpacityMicromapEXT;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `indexType` is the type of triangle indices used when indexing this micromap

- `indexBuffer` is the address containing the triangle indices

- `indexStride` is the byte stride between triangle indices

- `baseTriangle` is the base value added to the non-negative triangle indices

- `usageCountsCount` specifies the number of usage counts structures that will be used to determine the size of this micromap.

- `pUsageCounts` is a pointer to an array of VkMicromapUsageEXT structures.

- `ppUsageCounts` is a pointer to an array of pointers to VkMicromapUsageEXT structures.

- `micromap` is the handle to the micromap object to include in this geometry

If `VkAccelerationStructureTrianglesOpacityMicromapEXT` is included in the `pNext` chain of a VkAccelerationStructureGeometryTrianglesDataKHR structure, that geometry will reference that micromap.

For each triangle in the geometry, the acceleration structure build fetches an index from `indexBuffer` using `indexType` and `indexStride`. If that value is the unsigned cast of one of the values from VkOpacityMicromapSpecialIndexEXT then that triangle behaves as described for that special value in Ray Opacity Micromap. Otherwise that triangle uses the opacity micromap information from `micromap` at that index plus `baseTriangle`.

Only one of `pUsageCounts` or `ppUsageCounts` can be a valid pointer, the other must be `NULL`. The elements of the non-`NULL` array describe the total count used to build this geometry. For a given `format` and `subdivisionLevel` the number of triangles in this geometry matching those values after indirection and special index handling must be equal to the sum of matching `count` provided.

If `micromap` is VK_NULL_HANDLE, then every value read from `indexBuffer` must be one of the values in `VkOpacityMicromapSpecialIndexEXT`.

Valid Usage

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-pUsageCounts-07335
  Only one of `pUsageCounts` or `ppUsageCounts` can be a valid pointer, the other must be `NULL`

Valid Usage (Implicit)

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_TRIANGLES_OPACITY_MICROMAP_EXT`

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-indexType-parameter
  `indexType` must be a valid VkIndexType value

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-pUsageCounts-parameter
  If `usageCountsCount` is not `0`, and `pUsageCounts` is not `NULL`, `pUsageCounts` must be a valid pointer to an array of `usageCountsCount` VkMicromapUsageEXT structures

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-ppUsageCounts-parameter
  If `usageCountsCount` is not `0`, and `ppUsageCounts` is not `NULL`, `ppUsageCounts` must be a valid pointer to an array of `usageCountsCount` valid pointers to VkMicromapUsageEXT structures

- VUID-VkAccelerationStructureTrianglesOpacityMicromapEXT-micromap-parameter
  If `micromap` is not VK_NULL_HANDLE, `micromap` must be a valid VkMicromapEXT handle

The `VkOpacityMicromapSpecialIndexEXT` enumeration is defined as:

    // Provided by VK_EXT_opacity_micromap
    typedef enum VkOpacityMicromapSpecialIndexEXT {
        VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_TRANSPARENT_EXT = -1,
        VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_OPAQUE_EXT = -2,
        VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_UNKNOWN_TRANSPARENT_EXT = -3,
        VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_UNKNOWN_OPAQUE_EXT = -4,
    } VkOpacityMicromapSpecialIndexEXT;

- `VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_TRANSPARENT_EXT` specifies that the entire triangle is fully transparent.

- `VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_OPAQUE_EXT` specifies that the entire triangle is fully opaque.

- `VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_UNKNOWN_TRANSPARENT_EXT` specifies that the entire triangle is unknown-transparent.

- `VK_OPACITY_MICROMAP_SPECIAL_INDEX_FULLY_UNKNOWN_OPAQUE_EXT` specifies that the entire triangle is unknown-opaque.

The `VkAccelerationStructureTrianglesDisplacementMicromapNV` structure is defined as:

    // Provided by VK_NV_displacement_micromap
    typedef struct VkAccelerationStructureTrianglesDisplacementMicromapNV {
        VkStructureType                     sType;
        void*                               pNext;
        VkFormat                            displacementBiasAndScaleFormat;
        VkFormat                            displacementVectorFormat;
        VkDeviceOrHostAddressConstKHR       displacementBiasAndScaleBuffer;
        VkDeviceSize                        displacementBiasAndScaleStride;
        VkDeviceOrHostAddressConstKHR       displacementVectorBuffer;
        VkDeviceSize                        displacementVectorStride;
        VkDeviceOrHostAddressConstKHR       displacedMicromapPrimitiveFlags;
        VkDeviceSize                        displacedMicromapPrimitiveFlagsStride;
        VkIndexType                         indexType;
        VkDeviceOrHostAddressConstKHR       indexBuffer;
        VkDeviceSize                        indexStride;
        uint32_t                            baseTriangle;
        uint32_t                            usageCountsCount;
        const VkMicromapUsageEXT*           pUsageCounts;
        const VkMicromapUsageEXT* const*    ppUsageCounts;
        VkMicromapEXT                       micromap;
    } VkAccelerationStructureTrianglesDisplacementMicromapNV;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `displacementBiasAndScaleFormat` is the format of displacement bias and scale used in this displacement micromap reference.

- `displacementVectorFormat` is the format of displacement vector used in this displacement micromap reference.

- `displacementBiasAndScaleBuffer` is the address containing the bias and scale.

- `displacementBiasAndScaleStride` is the byte stride between bias and scale values.

- `displacementVectorBuffer` is the address containing the displacement vector values.

- `displacementVectorStride` is the byte stride between displacement vector values.

- `displacedMicromapPrimitiveFlags` is the address containing the primitive flags.

- `displacedMicromapPrimitiveFlagsStride` is the byte stride between primitive flag values.

- `indexType` is the type of triangle indices used when indexing this micromap.

- `indexBuffer` is the address containing the triangle indices.

- `indexStride` is the byte stride between triangle indices.

- `baseTriangle` is the base value added to the non-negative triangle indices.

- `usageCountsCount` specifies the number of usage counts structures that will be used to determine the size of this micromap.

- `pUsageCounts` is a pointer to an array of VkMicromapUsageEXT structures.

- `ppUsageCounts` is a pointer to an array of pointers to VkMicromapUsageEXT structures.

- `micromap` is the handle to the micromap object to include in this geometry.

If `VkAccelerationStructureTrianglesDisplacementMicromapNV` is included in the `pNext` chain of a VkAccelerationStructureGeometryTrianglesDataKHR structure, that geometry will reference that micromap.

For each triangle in the geometry, the acceleration structure build fetches an index from `indexBuffer` using `indexType` and `indexStride`. That triangle uses the displacement micromap information from `micromap` at that index plus `baseTriangle`.

Only one of `pUsageCounts` or `ppUsageCounts` can be a valid pointer, the other must be `NULL`. The elements of the non-`NULL` array describe the total count used to build this geometry. For a given `format` and `subdivisionLevel` the number of triangles in this geometry matching those values after indirection must be equal to the sum of matching `count` provided.

Valid Usage

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-displacementBiasAndScaleFormat-09501
  `displacementBiasAndScaleFormat` must not be `VK_FORMAT_UNDEFINED`

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-displacementVectorFormat-09502
  `displacementVectorFormat` must not be `VK_FORMAT_UNDEFINED`

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-pUsageCounts-07992
  Only one of `pUsageCounts` or `ppUsageCounts` can be a valid pointer, the other must be `NULL`

Valid Usage (Implicit)

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_TRIANGLES_DISPLACEMENT_MICROMAP_NV`

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-displacementBiasAndScaleFormat-parameter
  `displacementBiasAndScaleFormat` must be a valid VkFormat value

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-displacementVectorFormat-parameter
  `displacementVectorFormat` must be a valid VkFormat value

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-indexType-parameter
  `indexType` must be a valid VkIndexType value

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-pUsageCounts-parameter
  If `usageCountsCount` is not `0`, and `pUsageCounts` is not `NULL`, `pUsageCounts` must be a valid pointer to an array of `usageCountsCount` VkMicromapUsageEXT structures

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-ppUsageCounts-parameter
  If `usageCountsCount` is not `0`, and `ppUsageCounts` is not `NULL`, `ppUsageCounts` must be a valid pointer to an array of `usageCountsCount` valid pointers to VkMicromapUsageEXT structures

- VUID-VkAccelerationStructureTrianglesDisplacementMicromapNV-micromap-parameter
  If `micromap` is not VK_NULL_HANDLE, `micromap` must be a valid VkMicromapEXT handle

The `VkTransformMatrixKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkTransformMatrixKHR {
        float    matrix[3][4];
    } VkTransformMatrixKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkTransformMatrixKHR VkTransformMatrixNV;

- `matrix` is a 3x4 row-major affine transformation matrix.

Valid Usage

- VUID-VkTransformMatrixKHR-matrix-03799
  The first three columns of `matrix` must define an invertible 3x3 matrix

The `VkAccelerationStructureGeometryAabbsDataKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureGeometryAabbsDataKHR {
        VkStructureType                  sType;
        const void*                      pNext;
        VkDeviceOrHostAddressConstKHR    data;
        VkDeviceSize                     stride;
    } VkAccelerationStructureGeometryAabbsDataKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `data` is a device or host address to memory containing VkAabbPositionsKHR structures containing position data for each axis-aligned bounding box in the geometry.

- `stride` is the stride in bytes between each entry in `data`. The stride must be a multiple of `8`.

Valid Usage

- VUID-VkAccelerationStructureGeometryAabbsDataKHR-stride-03545
  `stride` must be a multiple of `8`

- VUID-VkAccelerationStructureGeometryAabbsDataKHR-stride-03820
  `stride` must be less than or equal to 232-1

Valid Usage (Implicit)

- VUID-VkAccelerationStructureGeometryAabbsDataKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_AABBS_DATA_KHR`

- VUID-VkAccelerationStructureGeometryAabbsDataKHR-pNext-pNext
  `pNext` must be `NULL`

The `VkAabbPositionsKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAabbPositionsKHR {
        float    minX;
        float    minY;
        float    minZ;
        float    maxX;
        float    maxY;
        float    maxZ;
    } VkAabbPositionsKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkAabbPositionsKHR VkAabbPositionsNV;

- `minX` is the x position of one opposing corner of a bounding box.

- `minY` is the y position of one opposing corner of a bounding box.

- `minZ` is the z position of one opposing corner of a bounding box.

- `maxX` is the x position of the other opposing corner of a bounding box.

- `maxY` is the y position of the other opposing corner of a bounding box.

- `maxZ` is the z position of the other opposing corner of a bounding box.

Valid Usage

- VUID-VkAabbPositionsKHR-minX-03546
  `minX` must be less than or equal to `maxX`

- VUID-VkAabbPositionsKHR-minY-03547
  `minY` must be less than or equal to `maxY`

- VUID-VkAabbPositionsKHR-minZ-03548
  `minZ` must be less than or equal to `maxZ`

The `VkAccelerationStructureGeometryInstancesDataKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureGeometryInstancesDataKHR {
        VkStructureType                  sType;
        const void*                      pNext;
        VkBool32                         arrayOfPointers;
        VkDeviceOrHostAddressConstKHR    data;
    } VkAccelerationStructureGeometryInstancesDataKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `arrayOfPointers` specifies whether `data` is used as an array of addresses or just an array.

- `data` is either the address of an array of device or host addresses referencing individual VkAccelerationStructureInstanceKHR structures or packed motion instance information as described in motion instances if `arrayOfPointers` is `VK_TRUE`, or the address of an array of VkAccelerationStructureInstanceKHR or VkAccelerationStructureMotionInstanceNV structures. Addresses and VkAccelerationStructureInstanceKHR structures are tightly packed. VkAccelerationStructureMotionInstanceNV structures have a stride of 160 bytes.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureGeometryInstancesDataKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_GEOMETRY_INSTANCES_DATA_KHR`

- VUID-VkAccelerationStructureGeometryInstancesDataKHR-pNext-pNext
  `pNext` must be `NULL`

Acceleration structure instances can be built into top-level acceleration structures. Each acceleration structure instance is a separate entry in the top-level acceleration structure which includes all the geometry of a bottom-level acceleration structure at a transformed location. Multiple instances can point to the same bottom level acceleration structure.

An acceleration structure instance is defined by the structure:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureInstanceKHR {
        VkTransformMatrixKHR          transform;
        uint32_t                      instanceCustomIndex:24;
        uint32_t                      mask:8;
        uint32_t                      instanceShaderBindingTableRecordOffset:24;
        VkGeometryInstanceFlagsKHR    flags:8;
        uint64_t                      accelerationStructureReference;
    } VkAccelerationStructureInstanceKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkAccelerationStructureInstanceKHR VkAccelerationStructureInstanceNV;

- `transform` is a VkTransformMatrixKHR structure describing a transformation to be applied to the acceleration structure.

- `instanceCustomIndex` is a 24-bit application-specified index value accessible to ray shaders in the `InstanceCustomIndexKHR` built-in.

- `mask` is an 8-bit visibility mask for the geometry. The instance may only be hit if `Cull Mask & instance.mask != 0`

- `instanceShaderBindingTableRecordOffset` is a 24-bit offset used in calculating the hit shader binding table index.

- `flags` is an 8-bit mask of VkGeometryInstanceFlagBitsKHR values to apply to this instance.

- `accelerationStructureReference` is either :

  - a device address containing the value obtained from vkGetAccelerationStructureDeviceAddressKHR or vkGetAccelerationStructureHandleNV (used by device operations which reference acceleration structures) or,

  - a VkAccelerationStructureKHR object (used by host operations which reference acceleration structures).

The C language specification does not define the ordering of bit-fields, but in practice, this struct produces the correct layout with existing compilers. The intended bit pattern is for the following:

- `instanceCustomIndex` and `mask` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceCustomIndex` occupies the 24 least significant bits of that memory

  - `mask` occupies the 8 most significant bits of that memory

- `instanceShaderBindingTableRecordOffset` and `flags` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceShaderBindingTableRecordOffset` occupies the 24 least significant bits of that memory

  - `flags` occupies the 8 most significant bits of that memory

If a compiler produces code that diverges from that pattern, applications must employ another method to set values according to the correct bit pattern.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureInstanceKHR-flags-parameter
  `flags` must be a valid combination of VkGeometryInstanceFlagBitsKHR values

Possible values of `flags` in the instance modifying the behavior of that instance are:

    // Provided by VK_KHR_acceleration_structure
    typedef enum VkGeometryInstanceFlagBitsKHR {
        VK_GEOMETRY_INSTANCE_TRIANGLE_FACING_CULL_DISABLE_BIT_KHR = 0x00000001,
        VK_GEOMETRY_INSTANCE_TRIANGLE_FLIP_FACING_BIT_KHR = 0x00000002,
        VK_GEOMETRY_INSTANCE_FORCE_OPAQUE_BIT_KHR = 0x00000004,
        VK_GEOMETRY_INSTANCE_FORCE_NO_OPAQUE_BIT_KHR = 0x00000008,
      // Provided by VK_EXT_opacity_micromap
        VK_GEOMETRY_INSTANCE_FORCE_OPACITY_MICROMAP_2_STATE_EXT = 0x00000010,
      // Provided by VK_EXT_opacity_micromap
        VK_GEOMETRY_INSTANCE_DISABLE_OPACITY_MICROMAPS_EXT = 0x00000020,
        VK_GEOMETRY_INSTANCE_TRIANGLE_FRONT_COUNTERCLOCKWISE_BIT_KHR = VK_GEOMETRY_INSTANCE_TRIANGLE_FLIP_FACING_BIT_KHR,
      // Provided by VK_NV_ray_tracing
        VK_GEOMETRY_INSTANCE_TRIANGLE_CULL_DISABLE_BIT_NV = VK_GEOMETRY_INSTANCE_TRIANGLE_FACING_CULL_DISABLE_BIT_KHR,
      // Provided by VK_NV_ray_tracing
        VK_GEOMETRY_INSTANCE_TRIANGLE_FRONT_COUNTERCLOCKWISE_BIT_NV = VK_GEOMETRY_INSTANCE_TRIANGLE_FRONT_COUNTERCLOCKWISE_BIT_KHR,
      // Provided by VK_NV_ray_tracing
        VK_GEOMETRY_INSTANCE_FORCE_OPAQUE_BIT_NV = VK_GEOMETRY_INSTANCE_FORCE_OPAQUE_BIT_KHR,
      // Provided by VK_NV_ray_tracing
        VK_GEOMETRY_INSTANCE_FORCE_NO_OPAQUE_BIT_NV = VK_GEOMETRY_INSTANCE_FORCE_NO_OPAQUE_BIT_KHR,
    } VkGeometryInstanceFlagBitsKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkGeometryInstanceFlagBitsKHR VkGeometryInstanceFlagBitsNV;

- `VK_GEOMETRY_INSTANCE_TRIANGLE_FACING_CULL_DISABLE_BIT_KHR` disables face culling for this instance.

- `VK_GEOMETRY_INSTANCE_TRIANGLE_FLIP_FACING_BIT_KHR` specifies that the facing determination for geometry in this instance is inverted. Because the facing is determined in object space, an instance transform does not change the winding, but a geometry transform does.

- `VK_GEOMETRY_INSTANCE_FORCE_OPAQUE_BIT_KHR` causes this instance to act as though `VK_GEOMETRY_OPAQUE_BIT_KHR` were specified on all geometries referenced by this instance. This behavior can be overridden by the SPIR-V `NoOpaqueKHR` ray flag.

- `VK_GEOMETRY_INSTANCE_FORCE_NO_OPAQUE_BIT_KHR` causes this instance to act as though `VK_GEOMETRY_OPAQUE_BIT_KHR` were not specified on all geometries referenced by this instance. This behavior can be overridden by the SPIR-V `OpaqueKHR` ray flag.

`VK_GEOMETRY_INSTANCE_FORCE_NO_OPAQUE_BIT_KHR` and `VK_GEOMETRY_INSTANCE_FORCE_OPAQUE_BIT_KHR` must not be used in the same flag.

    // Provided by VK_KHR_acceleration_structure
    typedef VkFlags VkGeometryInstanceFlagsKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkGeometryInstanceFlagsKHR VkGeometryInstanceFlagsNV;

`VkGeometryInstanceFlagsKHR` is a bitmask type for setting a mask of zero or more VkGeometryInstanceFlagBitsKHR.

Acceleration structure motion instances can be built into top-level acceleration structures. Each acceleration structure instance is a separate entry in the top-level acceleration structure which includes all the geometry of a bottom-level acceleration structure at a transformed location including a type of motion and parameters to determine the motion of the instance over time.

An acceleration structure motion instance is defined by the structure:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef struct VkAccelerationStructureMotionInstanceNV {
        VkAccelerationStructureMotionInstanceTypeNV     type;
        VkAccelerationStructureMotionInstanceFlagsNV    flags;
        VkAccelerationStructureMotionInstanceDataNV     data;
    } VkAccelerationStructureMotionInstanceNV;

- `type` is a VkAccelerationStructureMotionInstanceTypeNV enumerant identifying which type of motion instance this is and which type of the union is valid.

- `flags` is currently unused, but is required to keep natural alignment of `data`.

- `data` is a VkAccelerationStructureMotionInstanceDataNV containing motion instance data for this instance.

Note | If writing this other than with a standard C compiler, note that the final structure should be 152 bytes in size.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureMotionInstanceNV-type-parameter
  `type` must be a valid VkAccelerationStructureMotionInstanceTypeNV value

- VUID-VkAccelerationStructureMotionInstanceNV-flags-zerobitmask
  `flags` must be `0`

- VUID-VkAccelerationStructureMotionInstanceNV-staticInstance-parameter
  If `type` is `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_STATIC_NV`, the `staticInstance` member of `data` must be a valid VkAccelerationStructureInstanceKHR structure

- VUID-VkAccelerationStructureMotionInstanceNV-matrixMotionInstance-parameter
  If `type` is `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_MATRIX_MOTION_NV`, the `matrixMotionInstance` member of `data` must be a valid VkAccelerationStructureMatrixMotionInstanceNV structure

- VUID-VkAccelerationStructureMotionInstanceNV-srtMotionInstance-parameter
  If `type` is `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_SRT_MOTION_NV`, the `srtMotionInstance` member of `data` must be a valid VkAccelerationStructureSRTMotionInstanceNV structure

Acceleration structure motion instance is defined by the union:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef union VkAccelerationStructureMotionInstanceDataNV {
        VkAccelerationStructureInstanceKHR               staticInstance;
        VkAccelerationStructureMatrixMotionInstanceNV    matrixMotionInstance;
        VkAccelerationStructureSRTMotionInstanceNV       srtMotionInstance;
    } VkAccelerationStructureMotionInstanceDataNV;

- `staticInstance` is a VkAccelerationStructureInstanceKHR structure containing data for a static instance.

- `matrixMotionInstance` is a VkAccelerationStructureMatrixMotionInstanceNV structure containing data for a matrix motion instance.

- `srtMotionInstance` is a VkAccelerationStructureSRTMotionInstanceNV structure containing data for an SRT motion instance.

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef VkFlags VkAccelerationStructureMotionInstanceFlagsNV;

`VkAccelerationStructureMotionInstanceFlagsNV` is a bitmask type for setting a mask, but is currently reserved for future use.

The `VkAccelerationStructureMotionInstanceTypeNV` enumeration is defined as:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef enum VkAccelerationStructureMotionInstanceTypeNV {
        VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_STATIC_NV = 0,
        VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_MATRIX_MOTION_NV = 1,
        VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_SRT_MOTION_NV = 2,
    } VkAccelerationStructureMotionInstanceTypeNV;

- `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_STATIC_NV` specifies that the instance is a static instance with no instance motion.

- `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_MATRIX_MOTION_NV` specifies that the instance is a motion instance with motion specified by interpolation between two matrices.

- `VK_ACCELERATION_STRUCTURE_MOTION_INSTANCE_TYPE_SRT_MOTION_NV` specifies that the instance is a motion instance with motion specified by interpolation in the SRT decomposition.

An acceleration structure matrix motion instance is defined by the structure:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef struct VkAccelerationStructureMatrixMotionInstanceNV {
        VkTransformMatrixKHR          transformT0;
        VkTransformMatrixKHR          transformT1;
        uint32_t                      instanceCustomIndex:24;
        uint32_t                      mask:8;
        uint32_t                      instanceShaderBindingTableRecordOffset:24;
        VkGeometryInstanceFlagsKHR    flags:8;
        uint64_t                      accelerationStructureReference;
    } VkAccelerationStructureMatrixMotionInstanceNV;

- `transformT0` is a VkTransformMatrixKHR structure describing a transformation to be applied to the acceleration structure at time 0.

- `transformT1` is a VkTransformMatrixKHR structure describing a transformation to be applied to the acceleration structure at time 1.

- `instanceCustomIndex` is a 24-bit application-specified index value accessible to ray shaders in the `InstanceCustomIndexKHR` built-in.

- `mask` is an 8-bit visibility mask for the geometry. The instance may only be hit if `Cull Mask & instance.mask != 0`

- `instanceShaderBindingTableRecordOffset` is a 24-bit offset used in calculating the hit shader binding table index.

- `flags` is an 8-bit mask of VkGeometryInstanceFlagBitsKHR values to apply to this instance.

- `accelerationStructureReference` is either:

  - a device address containing the value obtained from vkGetAccelerationStructureDeviceAddressKHR or vkGetAccelerationStructureHandleNV (used by device operations which reference acceleration structures) or,

  - a VkAccelerationStructureKHR object (used by host operations which reference acceleration structures).

The C language specification does not define the ordering of bit-fields, but in practice, this struct produces the correct layout with existing compilers. The intended bit pattern is for the following:

- `instanceCustomIndex` and `mask` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceCustomIndex` occupies the 24 least significant bits of that memory

  - `mask` occupies the 8 most significant bits of that memory

- `instanceShaderBindingTableRecordOffset` and `flags` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceShaderBindingTableRecordOffset` occupies the 24 least significant bits of that memory

  - `flags` occupies the 8 most significant bits of that memory

If a compiler produces code that diverges from that pattern, applications must employ another method to set values according to the correct bit pattern.

The transform for a matrix motion instance at a point in time is derived by component-wise linear interpolation of the two transforms. That is, for a `time` in [0,1] the resulting transform is

  `transformT0` × (1 - `time`) + `transformT1` × `time`

Valid Usage (Implicit)

- VUID-VkAccelerationStructureMatrixMotionInstanceNV-flags-parameter
  `flags` must be a valid combination of VkGeometryInstanceFlagBitsKHR values

An acceleration structure SRT motion instance is defined by the structure:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef struct VkAccelerationStructureSRTMotionInstanceNV {
        VkSRTDataNV                   transformT0;
        VkSRTDataNV                   transformT1;
        uint32_t                      instanceCustomIndex:24;
        uint32_t                      mask:8;
        uint32_t                      instanceShaderBindingTableRecordOffset:24;
        VkGeometryInstanceFlagsKHR    flags:8;
        uint64_t                      accelerationStructureReference;
    } VkAccelerationStructureSRTMotionInstanceNV;

- `transformT0` is a VkSRTDataNV structure describing a transformation to be applied to the acceleration structure at time 0.

- `transformT1` is a VkSRTDataNV structure describing a transformation to be applied to the acceleration structure at time 1.

- `instanceCustomIndex` is a 24-bit application-specified index value accessible to ray shaders in the `InstanceCustomIndexKHR` built-in.

- `mask` is an 8-bit visibility mask for the geometry. The instance may only be hit if `Cull Mask & instance.mask != 0`

- `instanceShaderBindingTableRecordOffset` is a 24-bit offset used in calculating the hit shader binding table index.

- `flags` is an 8-bit mask of VkGeometryInstanceFlagBitsKHR values to apply to this instance.

- `accelerationStructureReference` is either:

  - a device address containing the value obtained from vkGetAccelerationStructureDeviceAddressKHR or vkGetAccelerationStructureHandleNV (used by device operations which reference acceleration structures) or,

  - a VkAccelerationStructureKHR object (used by host operations which reference acceleration structures).

The C language specification does not define the ordering of bit-fields, but in practice, this struct produces the correct layout with existing compilers. The intended bit pattern is for the following:

- `instanceCustomIndex` and `mask` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceCustomIndex` occupies the 24 least significant bits of that memory

  - `mask` occupies the 8 most significant bits of that memory

- `instanceShaderBindingTableRecordOffset` and `flags` occupy the same memory as if a single `uint32_t` was specified in their place

  - `instanceShaderBindingTableRecordOffset` occupies the 24 least significant bits of that memory

  - `flags` occupies the 8 most significant bits of that memory

If a compiler produces code that diverges from that pattern, applications must employ another method to set values according to the correct bit pattern.

The transform for a SRT motion instance at a point in time is derived from component-wise linear interpolation of the two SRT transforms. That is, for a `time` in [0,1] the resulting transform is

  `transformT0` × (1 - `time`) + `transformT1` × `time`

Valid Usage (Implicit)

- VUID-VkAccelerationStructureSRTMotionInstanceNV-flags-parameter
  `flags` must be a valid combination of VkGeometryInstanceFlagBitsKHR values

An acceleration structure SRT transform is defined by the structure:

    // Provided by VK_NV_ray_tracing_motion_blur
    typedef struct VkSRTDataNV {
        float    sx;
        float    a;
        float    b;
        float    pvx;
        float    sy;
        float    c;
        float    pvy;
        float    sz;
        float    pvz;
        float    qx;
        float    qy;
        float    qz;
        float    qw;
        float    tx;
        float    ty;
        float    tz;
    } VkSRTDataNV;

- `sx` is the x component of the scale of the transform

- `a` is one component of the shear for the transform

- `b` is one component of the shear for the transform

- `pvx` is the x component of the pivot point of the transform

- `sy` is the y component of the scale of the transform

- `c` is one component of the shear for the transform

- `pvy` is the y component of the pivot point of the transform

- `sz` is the z component of the scale of the transform

- `pvz` is the z component of the pivot point of the transform

- `qx` is the x component of the rotation quaternion

- `qy` is the y component of the rotation quaternion

- `qz` is the z component of the rotation quaternion

- `qw` is the w component of the rotation quaternion

- `tx` is the x component of the post-rotation translation

- `ty` is the y component of the post-rotation translation

- `tz` is the z component of the post-rotation translation

This transform decomposition consists of three elements. The first is a matrix S, consisting of a scale, shear, and translation, usually used to define the pivot point of the following rotation. This matrix is constructed from the parameters above by:

S=
​s x 0 0​a sy 0​b c sz​p vx p v y p v z​
​

The rotation quaternion is defined as:

  `R` = [ `qx`, `qy`, `qz`, `qw` ]

This is a rotation around a conceptual normalized axis [ ax, ay, az ] of amount `theta` such that:

  [ `qx`, `qy`, `qz` ] = sin(`theta`/2) × [ `ax`, `ay`, `az` ]

and

  `qw` = cos(`theta`/2)

Finally, the transform has a translation T constructed from the parameters above by:

T=
​1 0 0​0 1 0​0 0 1​t x t y t z​
​

The effective derived transform is then given by

  `T` × `R` × `S`

`VkAccelerationStructureBuildRangeInfoKHR` is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureBuildRangeInfoKHR {
        uint32_t    primitiveCount;
        uint32_t    primitiveOffset;
        uint32_t    firstVertex;
        uint32_t    transformOffset;
    } VkAccelerationStructureBuildRangeInfoKHR;

- `primitiveCount` defines the number of primitives for a corresponding acceleration structure geometry.

- `primitiveOffset` defines an offset in bytes into the memory where primitive data is defined.

- `firstVertex` is the index of the first vertex to build from for triangle geometry.

- `transformOffset` defines an offset in bytes into the memory where a transform matrix is defined.

The primitive count and primitive offset are interpreted differently depending on the VkGeometryTypeKHR used:

- For geometries of type `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `primitiveCount` is the number of triangles to be built, where each triangle is treated as 3 vertices.

  - If the geometry uses indices, `primitiveCount` × 3 indices are consumed from VkAccelerationStructureGeometryTrianglesDataKHR::`indexData`, starting at an offset of `primitiveOffset`. The value of `firstVertex` is added to the index values before fetching vertices.

  - If the geometry does not use indices, `primitiveCount` × 3 vertices are consumed from VkAccelerationStructureGeometryTrianglesDataKHR::`vertexData`, starting at an offset of `primitiveOffset` + VkAccelerationStructureGeometryTrianglesDataKHR::`vertexStride` × `firstVertex`.

  - If VkAccelerationStructureGeometryTrianglesDataKHR::`transformData` is not `NULL`, a single VkTransformMatrixKHR structure is consumed from VkAccelerationStructureGeometryTrianglesDataKHR::`transformData`, at an offset of `transformOffset`. This matrix describes a transformation from the space in which the vertices for all triangles in this geometry are described to the space in which the acceleration structure is defined.

- For geometries of type `VK_GEOMETRY_TYPE_AABBS_KHR`, `primitiveCount` is the number of axis-aligned bounding boxes. `primitiveCount` VkAabbPositionsKHR structures are consumed from VkAccelerationStructureGeometryAabbsDataKHR::`data`, starting at an offset of `primitiveOffset`.

- For geometries of type `VK_GEOMETRY_TYPE_INSTANCES_KHR`, `primitiveCount` is the number of acceleration structures. `primitiveCount` VkAccelerationStructureInstanceKHR or VkAccelerationStructureMotionInstanceNV structures are consumed from VkAccelerationStructureGeometryInstancesDataKHR::`data`, starting at an offset of `primitiveOffset`.

Valid Usage

- VUID-VkAccelerationStructureBuildRangeInfoKHR-primitiveOffset-03656
  For geometries of type `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if the geometry uses indices, the offset `primitiveOffset` from VkAccelerationStructureGeometryTrianglesDataKHR::`indexData` must be a multiple of the element size of VkAccelerationStructureGeometryTrianglesDataKHR::`indexType`

- VUID-VkAccelerationStructureBuildRangeInfoKHR-primitiveOffset-03657
  For geometries of type `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if the geometry does not use indices, the offset `primitiveOffset` from VkAccelerationStructureGeometryTrianglesDataKHR::`vertexData` must be a multiple of the component size of VkAccelerationStructureGeometryTrianglesDataKHR::`vertexFormat`

- VUID-VkAccelerationStructureBuildRangeInfoKHR-transformOffset-03658
  For geometries of type `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, the offset `transformOffset` from VkAccelerationStructureGeometryTrianglesDataKHR::`transformData` must be a multiple of 16

- VUID-VkAccelerationStructureBuildRangeInfoKHR-primitiveOffset-03659
  For geometries of type `VK_GEOMETRY_TYPE_AABBS_KHR`, the offset `primitiveOffset` from VkAccelerationStructureGeometryAabbsDataKHR::`data` must be a multiple of 8

- VUID-VkAccelerationStructureBuildRangeInfoKHR-primitiveOffset-03660
  For geometries of type `VK_GEOMETRY_TYPE_INSTANCES_KHR`, the offset `primitiveOffset` from VkAccelerationStructureGeometryInstancesDataKHR::`data` must be a multiple of 16

#### 37.1.8. Copying Acceleration Structures

An additional command exists for copying acceleration structures without updating their contents. The acceleration structure object can be compacted in order to improve performance. Before copying, an application must query the size of the resulting acceleration structure.

To query acceleration structure size parameters call:

    // Provided by VK_KHR_acceleration_structure
    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-accelerationStructure-08924
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

- 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-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-parameter
  `pAccelerationStructures` must be a valid pointer to an array of `accelerationStructureCount` valid VkAccelerationStructureKHR handles

- VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-queryType-parameter
  `queryType` must be a valid VkQueryType value

- VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-queryPool-parameter
  `queryPool` must be a valid VkQueryPool handle

- VUID-vkCmdWriteAccelerationStructuresPropertiesKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- 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-accelerationStructureCount-arraylength
  `accelerationStructureCount` must be greater than `0`

- 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

Command Properties

Command Buffer Levels | Render Pass Scope | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

To query acceleration structure size parameters call:

    // Provided by VK_NV_ray_tracing
    void vkCmdWriteAccelerationStructuresPropertiesNV(
        VkCommandBuffer                             commandBuffer,
        uint32_t                                    accelerationStructureCount,
        const VkAccelerationStructureNV*            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_ACCELERATION_STRUCTURE_BUILD_BIT_KHR` pipeline stage and an access type of `VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR`.

Valid Usage

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-queryPool-03755
  `queryPool` must have been created with a `queryType` matching `queryType`

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-queryPool-03756
  The queries identified by `queryPool` and `firstQuery` must be unavailable

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-accelerationStructure-03757
  `accelerationStructure` must be bound completely and contiguously to a single `VkDeviceMemory` object via vkBindAccelerationStructureMemoryNV

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-pAccelerationStructures-04958
  All acceleration structures in `pAccelerationStructures` must have been built prior to the execution of this command

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-pAccelerationStructures-06215
  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_NV`

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-queryType-06216
  `queryType` must be `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_NV`

Valid Usage (Implicit)

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-pAccelerationStructures-parameter
  `pAccelerationStructures` must be a valid pointer to an array of `accelerationStructureCount` valid VkAccelerationStructureNV handles

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-queryType-parameter
  `queryType` must be a valid VkQueryType value

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-queryPool-parameter
  `queryPool` must be a valid VkQueryPool handle

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-videocoding
  This command must only be called outside of a video coding scope

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-accelerationStructureCount-arraylength
  `accelerationStructureCount` must be greater than `0`

- VUID-vkCmdWriteAccelerationStructuresPropertiesNV-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

Command Properties

Command Buffer Levels | Render Pass Scope | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

To copy an acceleration structure call:

    // Provided by VK_NV_ray_tracing
    void vkCmdCopyAccelerationStructureNV(
        VkCommandBuffer                             commandBuffer,
        VkAccelerationStructureNV                   dst,
        VkAccelerationStructureNV                   src,
        VkCopyAccelerationStructureModeKHR          mode);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `dst` is the target acceleration structure for the copy.

- `src` is the source acceleration structure for the copy.

- `mode` is a VkCopyAccelerationStructureModeKHR value specifying additional operations to perform during the copy.

Accesses to `src` and `dst` 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` or `VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR` as appropriate.

Valid Usage

- VUID-vkCmdCopyAccelerationStructureNV-mode-03410
  `mode` must be `VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR` or `VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_KHR`

- VUID-vkCmdCopyAccelerationStructureNV-src-04963
  The source acceleration structure `src` must have been constructed prior to the execution of this command

- VUID-vkCmdCopyAccelerationStructureNV-src-03411
  If `mode` is `VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR`, `src` must have been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_COMPACTION_BIT_KHR` in the build

- VUID-vkCmdCopyAccelerationStructureNV-buffer-03718
  The `buffer` used to create `src` must be bound to device memory

- VUID-vkCmdCopyAccelerationStructureNV-buffer-03719
  The `buffer` used to create `dst` must be bound to device memory

- VUID-vkCmdCopyAccelerationStructureNV-dst-07791
  The range of memory backing `dst` that is accessed by this command must not overlap the memory backing `src` that is accessed by this command

- VUID-vkCmdCopyAccelerationStructureNV-dst-07792
  `dst` must be bound completely and contiguously to a single `VkDeviceMemory` object via vkBindAccelerationStructureMemoryNV

Valid Usage (Implicit)

- VUID-vkCmdCopyAccelerationStructureNV-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdCopyAccelerationStructureNV-dst-parameter
  `dst` must be a valid VkAccelerationStructureNV handle

- VUID-vkCmdCopyAccelerationStructureNV-src-parameter
  `src` must be a valid VkAccelerationStructureNV handle

- VUID-vkCmdCopyAccelerationStructureNV-mode-parameter
  `mode` must be a valid VkCopyAccelerationStructureModeKHR value

- VUID-vkCmdCopyAccelerationStructureNV-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdCopyAccelerationStructureNV-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdCopyAccelerationStructureNV-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdCopyAccelerationStructureNV-videocoding
  This command must only be called outside of a video coding scope

- VUID-vkCmdCopyAccelerationStructureNV-commonparent
  Each of `commandBuffer`, `dst`, and `src` 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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

To copy an acceleration structure call:

    // Provided by VK_KHR_acceleration_structure
    void vkCmdCopyAccelerationStructureKHR(
        VkCommandBuffer                             commandBuffer,
        const VkCopyAccelerationStructureInfoKHR*   pInfo);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `pInfo` is a pointer to a VkCopyAccelerationStructureInfoKHR structure defining the copy operation.

This command copies the `pInfo->src` acceleration structure to the `pInfo->dst` acceleration structure in the manner specified by `pInfo->mode`.

Accesses to `pInfo->src` and `pInfo->dst` 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` or `VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR` as appropriate.

Valid Usage

- VUID-vkCmdCopyAccelerationStructureKHR-accelerationStructure-08925
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

- VUID-vkCmdCopyAccelerationStructureKHR-buffer-03737
  The `buffer` used to create `pInfo->src` must be bound to device memory

- VUID-vkCmdCopyAccelerationStructureKHR-buffer-03738
  The `buffer` used to create `pInfo->dst` must be bound to device memory

Valid Usage (Implicit)

- VUID-vkCmdCopyAccelerationStructureKHR-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdCopyAccelerationStructureKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyAccelerationStructureInfoKHR structure

- VUID-vkCmdCopyAccelerationStructureKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdCopyAccelerationStructureKHR-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdCopyAccelerationStructureKHR-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdCopyAccelerationStructureKHR-videocoding
  This command must only be called outside of a video coding scope

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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

The `VkCopyAccelerationStructureInfoKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkCopyAccelerationStructureInfoKHR {
        VkStructureType                       sType;
        const void*                           pNext;
        VkAccelerationStructureKHR            src;
        VkAccelerationStructureKHR            dst;
        VkCopyAccelerationStructureModeKHR    mode;
    } VkCopyAccelerationStructureInfoKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `src` is the source acceleration structure for the copy.

- `dst` is the target acceleration structure for the copy.

- `mode` is a VkCopyAccelerationStructureModeKHR value specifying additional operations to perform during the copy.

Valid Usage

- VUID-VkCopyAccelerationStructureInfoKHR-mode-03410
  `mode` must be `VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR` or `VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_KHR`

- VUID-VkCopyAccelerationStructureInfoKHR-src-04963
  The source acceleration structure `src` must have been constructed prior to the execution of this command

- VUID-VkCopyAccelerationStructureInfoKHR-src-03411
  If `mode` is `VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR`, `src` must have been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_COMPACTION_BIT_KHR` in the build

- VUID-VkCopyAccelerationStructureInfoKHR-buffer-03718
  The `buffer` used to create `src` must be bound to device memory

- VUID-VkCopyAccelerationStructureInfoKHR-buffer-03719
  The `buffer` used to create `dst` must be bound to device memory

- VUID-VkCopyAccelerationStructureInfoKHR-dst-07791
  The range of memory backing `dst` that is accessed by this command must not overlap the memory backing `src` that is accessed by this command

Valid Usage (Implicit)

- VUID-VkCopyAccelerationStructureInfoKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_COPY_ACCELERATION_STRUCTURE_INFO_KHR`

- VUID-VkCopyAccelerationStructureInfoKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkCopyAccelerationStructureInfoKHR-src-parameter
  `src` must be a valid VkAccelerationStructureKHR handle

- VUID-VkCopyAccelerationStructureInfoKHR-dst-parameter
  `dst` must be a valid VkAccelerationStructureKHR handle

- VUID-VkCopyAccelerationStructureInfoKHR-mode-parameter
  `mode` must be a valid VkCopyAccelerationStructureModeKHR value

- VUID-VkCopyAccelerationStructureInfoKHR-commonparent
  Both of `dst`, and `src` must have been created, allocated, or retrieved from the same VkDevice

Possible values of `mode` specifying additional operations to perform during the copy, are:

    // Provided by VK_KHR_acceleration_structure
    typedef enum VkCopyAccelerationStructureModeKHR {
        VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_KHR = 0,
        VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR = 1,
      // Provided by VK_KHR_acceleration_structure
        VK_COPY_ACCELERATION_STRUCTURE_MODE_SERIALIZE_KHR = 2,
      // Provided by VK_KHR_acceleration_structure
        VK_COPY_ACCELERATION_STRUCTURE_MODE_DESERIALIZE_KHR = 3,
      // Provided by VK_NV_ray_tracing
        VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_NV = VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_KHR,
      // Provided by VK_NV_ray_tracing
        VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_NV = VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR,
    } VkCopyAccelerationStructureModeKHR;

or the equivalent

    // Provided by VK_NV_ray_tracing
    typedef VkCopyAccelerationStructureModeKHR VkCopyAccelerationStructureModeNV;

- `VK_COPY_ACCELERATION_STRUCTURE_MODE_CLONE_KHR` creates a direct copy of the acceleration structure specified in `src` into the one specified by `dst`. The `dst` acceleration structure must have been created with the same parameters as `src`. If `src` contains references to other acceleration structures, `dst` will reference the same acceleration structures.

- `VK_COPY_ACCELERATION_STRUCTURE_MODE_COMPACT_KHR` creates a more compact version of an acceleration structure `src` into `dst`. The acceleration structure `dst` must have been created with a size at least as large as that returned by vkCmdWriteAccelerationStructuresPropertiesNV , vkCmdWriteAccelerationStructuresPropertiesKHR, or vkWriteAccelerationStructuresPropertiesKHR after the build of the acceleration structure specified by `src`. If `src` contains references to other acceleration structures, `dst` will reference the same acceleration structures.

- `VK_COPY_ACCELERATION_STRUCTURE_MODE_SERIALIZE_KHR` serializes the acceleration structure to a semi-opaque format which can be reloaded on a compatible implementation.

- `VK_COPY_ACCELERATION_STRUCTURE_MODE_DESERIALIZE_KHR` deserializes the semi-opaque serialization format in the buffer to the acceleration structure.

To copy an acceleration structure to device memory call:

    // Provided by VK_KHR_acceleration_structure
    void vkCmdCopyAccelerationStructureToMemoryKHR(
        VkCommandBuffer                             commandBuffer,
        const VkCopyAccelerationStructureToMemoryInfoKHR* pInfo);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `pInfo` is an a pointer to a VkCopyAccelerationStructureToMemoryInfoKHR structure defining the copy operation.

Accesses to `pInfo->src` 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`. Accesses to the buffer indicated by `pInfo->dst.deviceAddress` 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 and an access type of `VK_ACCESS_TRANSFER_WRITE_BIT`.

This command produces the same results as vkCopyAccelerationStructureToMemoryKHR, but writes its result to a device address, and is executed on the device rather than the host. The output may not necessarily be bit-for-bit identical, but it can be equally used by either vkCmdCopyMemoryToAccelerationStructureKHR or vkCopyMemoryToAccelerationStructureKHR.

The defined header structure for the serialized data consists of:

- `VK_UUID_SIZE` bytes of data matching `VkPhysicalDeviceIDProperties`::`driverUUID`

- `VK_UUID_SIZE` bytes of data identifying the compatibility for comparison using vkGetDeviceAccelerationStructureCompatibilityKHR

- A 64-bit integer of the total size matching the value queried using `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR`

- A 64-bit integer of the deserialized size to be passed in to `VkAccelerationStructureCreateInfoKHR`::`size`

- A 64-bit integer of the count of the number of acceleration structure handles following. This value matches the value queried using `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_BOTTOM_LEVEL_POINTERS_KHR`. This will be zero for a bottom-level acceleration structure. For top-level acceleration structures this number is implementation-dependent; the number of and ordering of the handles may not match the instance descriptions which were used to build the acceleration structure.

The corresponding handles matching the values returned by vkGetAccelerationStructureDeviceAddressKHR or vkGetAccelerationStructureHandleNV are tightly packed in the buffer following the count. The application is expected to store a mapping between those handles and the original application-generated bottom-level acceleration structures to provide when deserializing. The serialized data is written to the buffer (or read from the buffer) according to the host endianness.

Valid Usage

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-accelerationStructure-08926
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-pInfo-03739
  `pInfo->dst.deviceAddress` must be a valid device address for a buffer bound to device memory

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-pInfo-03740
  `pInfo->dst.deviceAddress` must be aligned to `256` bytes

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-pInfo-03741
  If the buffer pointed to by `pInfo->dst.deviceAddress` is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-None-03559
  The `buffer` used to create `pInfo->src` must be bound to device memory

Valid Usage (Implicit)

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyAccelerationStructureToMemoryInfoKHR structure

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdCopyAccelerationStructureToMemoryKHR-videocoding
  This command must only be called outside of a video coding scope

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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkCopyAccelerationStructureToMemoryInfoKHR {
        VkStructureType                       sType;
        const void*                           pNext;
        VkAccelerationStructureKHR            src;
        VkDeviceOrHostAddressKHR              dst;
        VkCopyAccelerationStructureModeKHR    mode;
    } VkCopyAccelerationStructureToMemoryInfoKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `src` is the source acceleration structure for the copy

- `dst` is the device or host address to memory which is the target for the copy

- `mode` is a VkCopyAccelerationStructureModeKHR value specifying additional operations to perform during the copy.

Valid Usage

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-src-04959
  The source acceleration structure `src` must have been constructed prior to the execution of this command

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-dst-03561
  The memory pointed to by `dst` must be at least as large as the serialization size of `src`, as reported by vkWriteAccelerationStructuresPropertiesKHR or vkCmdWriteAccelerationStructuresPropertiesKHR with a query type of `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR`

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-mode-03412
  `mode` must be `VK_COPY_ACCELERATION_STRUCTURE_MODE_SERIALIZE_KHR`

Valid Usage (Implicit)

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_COPY_ACCELERATION_STRUCTURE_TO_MEMORY_INFO_KHR`

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-src-parameter
  `src` must be a valid VkAccelerationStructureKHR handle

- VUID-VkCopyAccelerationStructureToMemoryInfoKHR-mode-parameter
  `mode` must be a valid VkCopyAccelerationStructureModeKHR value

To copy device memory to an acceleration structure call:

    // Provided by VK_KHR_acceleration_structure
    void vkCmdCopyMemoryToAccelerationStructureKHR(
        VkCommandBuffer                             commandBuffer,
        const VkCopyMemoryToAccelerationStructureInfoKHR* pInfo);

- `commandBuffer` is the command buffer into which the command will be recorded.

- `pInfo` is a pointer to a VkCopyMemoryToAccelerationStructureInfoKHR structure defining the copy operation.

Accesses to `pInfo->dst` 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_WRITE_BIT_KHR`. Accesses to the buffer indicated by `pInfo->src.deviceAddress` 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_TRANSFER_READ_BIT`.

This command can accept acceleration structures produced by either vkCmdCopyAccelerationStructureToMemoryKHR or vkCopyAccelerationStructureToMemoryKHR.

The structure provided as input to deserialize is as described in vkCmdCopyAccelerationStructureToMemoryKHR, with any acceleration structure handles filled in with the newly-queried handles to bottom level acceleration structures created before deserialization. These do not need to be built at deserialize time, but must be created.

Valid Usage

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-accelerationStructure-08927
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-pInfo-03742
  `pInfo->src.deviceAddress` must be a valid device address for a buffer bound to device memory

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-pInfo-03743
  `pInfo->src.deviceAddress` must be aligned to `256` bytes

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-pInfo-03744
  If the buffer pointed to by `pInfo->src.deviceAddress` is non-sparse then it must be bound completely and contiguously to a single VkDeviceMemory object

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-buffer-03745
  The `buffer` used to create `pInfo->dst` must be bound to device memory

Valid Usage (Implicit)

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-commandBuffer-parameter
  `commandBuffer` must be a valid VkCommandBuffer handle

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyMemoryToAccelerationStructureInfoKHR structure

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-commandBuffer-recording
  `commandBuffer` must be in the recording state

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-commandBuffer-cmdpool
  The `VkCommandPool` that `commandBuffer` was allocated from must support compute operations

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-renderpass
  This command must only be called outside of a render pass instance

- VUID-vkCmdCopyMemoryToAccelerationStructureKHR-videocoding
  This command must only be called outside of a video coding scope

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 | Video Coding Scope | Supported Queue Types | Command Type
--- | --- | --- | --- | ---
Primary Secondary | Outside | Outside | Compute | Action

The `VkCopyMemoryToAccelerationStructureInfoKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkCopyMemoryToAccelerationStructureInfoKHR {
        VkStructureType                       sType;
        const void*                           pNext;
        VkDeviceOrHostAddressConstKHR         src;
        VkAccelerationStructureKHR            dst;
        VkCopyAccelerationStructureModeKHR    mode;
    } VkCopyMemoryToAccelerationStructureInfoKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `src` is the device or host address to memory containing the source data for the copy.

- `dst` is the target acceleration structure for the copy.

- `mode` is a VkCopyAccelerationStructureModeKHR value specifying additional operations to perform during the copy.

Valid Usage

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-src-04960
  The source memory pointed to by `src` must contain data previously serialized using vkCmdCopyAccelerationStructureToMemoryKHR, potentially modified to relocate acceleration structure references as described in that command

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-mode-03413
  `mode` must be `VK_COPY_ACCELERATION_STRUCTURE_MODE_DESERIALIZE_KHR`

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-pInfo-03414
  The data in `src` must have a format compatible with the destination physical device as returned by vkGetDeviceAccelerationStructureCompatibilityKHR

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-dst-03746
  `dst` must have been created with a `size` greater than or equal to that used to serialize the data in `src`

Valid Usage (Implicit)

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_COPY_MEMORY_TO_ACCELERATION_STRUCTURE_INFO_KHR`

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-dst-parameter
  `dst` must be a valid VkAccelerationStructureKHR handle

- VUID-VkCopyMemoryToAccelerationStructureInfoKHR-mode-parameter
  `mode` must be a valid VkCopyAccelerationStructureModeKHR value

To check if a serialized acceleration structure is compatible with the current device call:

    // Provided by VK_KHR_acceleration_structure
    void vkGetDeviceAccelerationStructureCompatibilityKHR(
        VkDevice                                    device,
        const VkAccelerationStructureVersionInfoKHR* pVersionInfo,
        VkAccelerationStructureCompatibilityKHR*    pCompatibility);

- `device` is the device to check the version against.

- `pVersionInfo` is a pointer to a VkAccelerationStructureVersionInfoKHR structure specifying version information to check against the device.

- `pCompatibility` is a pointer to a VkAccelerationStructureCompatibilityKHR value in which compatibility information is returned.

Valid Usage

- VUID-vkGetDeviceAccelerationStructureCompatibilityKHR-accelerationStructure-08928
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructure` feature must be enabled

Valid Usage (Implicit)

- VUID-vkGetDeviceAccelerationStructureCompatibilityKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkGetDeviceAccelerationStructureCompatibilityKHR-pVersionInfo-parameter
  `pVersionInfo` must be a valid pointer to a valid VkAccelerationStructureVersionInfoKHR structure

- VUID-vkGetDeviceAccelerationStructureCompatibilityKHR-pCompatibility-parameter
  `pCompatibility` must be a valid pointer to a VkAccelerationStructureCompatibilityKHR value

The `VkAccelerationStructureVersionInfoKHR` structure is defined as:

    // Provided by VK_KHR_acceleration_structure
    typedef struct VkAccelerationStructureVersionInfoKHR {
        VkStructureType    sType;
        const void*        pNext;
        const uint8_t*     pVersionData;
    } VkAccelerationStructureVersionInfoKHR;

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `pVersionData` is a pointer to the version header of an acceleration structure as defined in vkCmdCopyAccelerationStructureToMemoryKHR

Note | `pVersionData` is a pointer to an array of 2×`VK_UUID_SIZE` `uint8_t` values instead of two `VK_UUID_SIZE` arrays as the expected use case for this member is to be pointed at the header of a previously serialized acceleration structure (via vkCmdCopyAccelerationStructureToMemoryKHR or vkCopyAccelerationStructureToMemoryKHR) that is loaded in memory. Using arrays would necessitate extra memory copies of the UUIDs.

Valid Usage (Implicit)

- VUID-VkAccelerationStructureVersionInfoKHR-sType-sType
  `sType` must be `VK_STRUCTURE_TYPE_ACCELERATION_STRUCTURE_VERSION_INFO_KHR`

- VUID-VkAccelerationStructureVersionInfoKHR-pNext-pNext
  `pNext` must be `NULL`

- VUID-VkAccelerationStructureVersionInfoKHR-pVersionData-parameter
  `pVersionData` must be a valid pointer to an array of 2×VK_UUID_SIZE `uint8_t` values

Possible values of `pCompatibility` returned by vkGetDeviceAccelerationStructureCompatibilityKHR are:

    // Provided by VK_KHR_acceleration_structure
    typedef enum VkAccelerationStructureCompatibilityKHR {
        VK_ACCELERATION_STRUCTURE_COMPATIBILITY_COMPATIBLE_KHR = 0,
        VK_ACCELERATION_STRUCTURE_COMPATIBILITY_INCOMPATIBLE_KHR = 1,
    } VkAccelerationStructureCompatibilityKHR;

- `VK_ACCELERATION_STRUCTURE_COMPATIBILITY_COMPATIBLE_KHR` if the `pVersionData` version acceleration structure is compatible with `device`.

- `VK_ACCELERATION_STRUCTURE_COMPATIBILITY_INCOMPATIBLE_KHR` if the `pVersionData` version acceleration structure is not compatible with `device`.

### 37.2. Host Acceleration Structure Operations

Implementations are also required to provide host implementations of the acceleration structure operations if the `accelerationStructureHostCommands` feature is enabled:

- vkBuildAccelerationStructuresKHR corresponding to vkCmdBuildAccelerationStructuresKHR

- vkCopyAccelerationStructureKHR corresponding to vkCmdCopyAccelerationStructureKHR

- vkCopyAccelerationStructureToMemoryKHR corresponding to vkCmdCopyAccelerationStructureToMemoryKHR

- vkCopyMemoryToAccelerationStructureKHR corresponding to vkCmdCopyMemoryToAccelerationStructureKHR

- vkWriteAccelerationStructuresPropertiesKHR corresponding to vkCmdWriteAccelerationStructuresPropertiesKHR

These commands are functionally equivalent to their device counterparts, except that they are executed on the host timeline, rather than being enqueued into command buffers.

All acceleration structures used by the host commands must be bound to host-visible memory, and all input data for acceleration structure builds must be referenced using host addresses instead of device addresses. Applications are not required to map acceleration structure memory when using the host commands.

Note | The vkBuildAccelerationStructuresKHR and vkCmdBuildAccelerationStructuresKHR may use different algorithms, and thus are not required to produce identical structures. The structures produced by these two commands may exhibit different memory footprints or traversal performance, but should strive to be similar where possible. Apart from these details, the host and device operations are interchangeable. For example, an application can use vkBuildAccelerationStructuresKHR to build a structure, compact it on the device using vkCmdCopyAccelerationStructureKHR, and serialize the result using vkCopyAccelerationStructureToMemoryKHR.

Note | For efficient execution, acceleration structures manipulated using these commands should always be bound to host cached memory, as the implementation may need to repeatedly read and write this memory during the execution of the command.

To build acceleration structures on the host, call:

    // Provided by VK_KHR_acceleration_structure
    VkResult vkBuildAccelerationStructuresKHR(
        VkDevice                                    device,
        VkDeferredOperationKHR                      deferredOperation,
        uint32_t                                    infoCount,
        const VkAccelerationStructureBuildGeometryInfoKHR* pInfos,
        const VkAccelerationStructureBuildRangeInfoKHR* const* ppBuildRangeInfos);

- `device` is the `VkDevice` for which the acceleration structures are being built.

- `deferredOperation` is an optional VkDeferredOperationKHR to request deferral for this command.

- `infoCount` is the number of acceleration structures to build. It specifies the number of the `pInfos` structures and `ppBuildRangeInfos` pointers that must be provided.

- `pInfos` is a pointer to an array of `infoCount` VkAccelerationStructureBuildGeometryInfoKHR structures defining the geometry used to build each acceleration structure.

- `ppBuildRangeInfos` is a pointer to an array of `infoCount` pointers to arrays of VkAccelerationStructureBuildRangeInfoKHR structures. Each `ppBuildRangeInfos`[i] is a pointer to an array of `pInfos`[i].`geometryCount` VkAccelerationStructureBuildRangeInfoKHR structures defining dynamic offsets to the addresses where geometry data is stored, as defined by `pInfos`[i].

This command fulfills the same task as vkCmdBuildAccelerationStructuresKHR but is executed by the host.

The `vkBuildAccelerationStructuresKHR` command provides the ability to initiate multiple acceleration structures builds, however there is no ordering or synchronization implied between any of the individual acceleration structure builds.

Note | This means that an application cannot build a top-level acceleration structure in the same vkBuildAccelerationStructuresKHR call as the associated bottom-level or instance acceleration structures are being built. There also cannot be any memory aliasing between any acceleration structure memories or scratch memories being used by any of the builds.

Valid Usage

- VUID-vkBuildAccelerationStructuresKHR-accelerationStructureHostCommands-03581
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureHostCommands` feature must be enabled

- VUID-vkBuildAccelerationStructuresKHR-mode-04628
  The `mode` member of each element of `pInfos` must be a valid VkBuildAccelerationStructureModeKHR value

- VUID-vkBuildAccelerationStructuresKHR-srcAccelerationStructure-04629
  If the `srcAccelerationStructure` member of any element of `pInfos` is not VK_NULL_HANDLE, the `srcAccelerationStructure` member must be a valid VkAccelerationStructureKHR handle

- VUID-vkBuildAccelerationStructuresKHR-pInfos-04630
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must not be VK_NULL_HANDLE

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03403
  The `srcAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03698
  The `dstAccelerationStructure` member of any element of `pInfos` must not be the same acceleration structure as the `dstAccelerationStructure` member of any other element of `pInfos`

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03800
  The `dstAccelerationStructure` member of any element of `pInfos` must be a valid VkAccelerationStructureKHR handle

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03699
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_TOP_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03700
  For each element of `pInfos`, if its `type` member is `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR`, its `dstAccelerationStructure` member must have been created with a value of VkAccelerationStructureCreateInfoKHR::`type` equal to either `VK_ACCELERATION_STRUCTURE_TYPE_BOTTOM_LEVEL_KHR` or `VK_ACCELERATION_STRUCTURE_TYPE_GENERIC_KHR`

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03663
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, inactive primitives in its `srcAccelerationStructure` member must not be made active

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03664
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, active primitives in its `srcAccelerationStructure` member must not be made inactive

- VUID-vkBuildAccelerationStructuresKHR-None-03407
  The `dstAccelerationStructure` member of any element of `pInfos` must not be referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03701
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any other element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03702
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `dstAccelerationStructure` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03703
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any element of `pInfos` (including the same element), which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-scratchData-03704
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `scratchData` member of any other element of `pInfos`, which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-scratchData-03705
  The range of memory backing the `scratchData` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing the `srcAccelerationStructure` member of any element of `pInfos` with a `mode` equal to `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` (including the same element), which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-dstAccelerationStructure-03706
  The range of memory backing the `dstAccelerationStructure` member of any element of `pInfos` that is accessed by this command must not overlap the memory backing any acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` in any other element of `pInfos`, which is accessed by this command

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03667
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` member must have previously been constructed with `VK_BUILD_ACCELERATION_STRUCTURE_ALLOW_UPDATE_BIT_KHR` set in VkAccelerationStructureBuildGeometryInfoKHR::`flags` in the build

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03668
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `srcAccelerationStructure` and `dstAccelerationStructure` members must either be the same VkAccelerationStructureKHR, or not have any memory aliasing

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03758
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `geometryCount` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03759
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03760
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, its `type` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03761
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `geometryType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03762
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, its `flags` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03763
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.vertexFormat` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03764
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.maxVertex` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03765
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, its `geometry.triangles.indexType` member must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03766
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was `NULL` when `srcAccelerationStructure` was last built, then it must be `NULL`

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03767
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if its `geometry.triangles.transformData` address was not `NULL` when `srcAccelerationStructure` was last built, then it must not be `NULL`

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03768
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, if `geometryType` is `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, and `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, then the value of each index referenced must be the same as the corresponding index value when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-primitiveCount-03769
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, then for each `VkAccelerationStructureGeometryKHR` structure referred to by its `pGeometries` or `ppGeometries` members, the `primitiveCount` member of its corresponding `VkAccelerationStructureBuildRangeInfoKHR` structure must have the same value which was specified when `srcAccelerationStructure` was last built

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03801
  For each element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, the corresponding `ppBuildRangeInfos`[i][j].`primitiveCount` must be less than or equal to VkPhysicalDeviceAccelerationStructurePropertiesKHR::`maxInstanceCount`

- VUID-vkBuildAccelerationStructuresKHR-pInfos-10126
  For each `pInfos`[i], `dstAccelerationStructure` must have been created with a value of VkAccelerationStructureCreateInfoKHR::`size` greater than or equal to either:

  - the memory size required by the build operation, as returned by vkGetAccelerationStructureBuildSizesKHR with `pBuildInfo` = `pInfos`[i] and with each element of the `pMaxPrimitiveCounts` array greater than or equal to the equivalent `ppBuildRangeInfos`[i][j].`primitiveCount` values for `j` in [0,`pInfos`[i].`geometryCount`) or,

  - the result of querying the corresponding `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR`, if updating a compacted acceleration structure

- VUID-vkBuildAccelerationStructuresKHR-ppBuildRangeInfos-03676
  Each element of `ppBuildRangeInfos`[i] must be a valid pointer to an array of `pInfos`[i].`geometryCount` `VkAccelerationStructureBuildRangeInfoKHR` structures

- VUID-vkBuildAccelerationStructuresKHR-deferredOperation-03678
  Any previous deferred operation that was associated with `deferredOperation` must be complete

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03722
  For each element of `pInfos`, the `buffer` used to create its `dstAccelerationStructure` member must be bound to host-visible device memory

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03723
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` the `buffer` used to create its `srcAccelerationStructure` member must be bound to host-visible device memory

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03724
  For each element of `pInfos`, the `buffer` used to create each acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` must be bound to host-visible device memory

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03725
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_BUILD_KHR`, all addresses between `pInfos`[i].`scratchData.hostAddress` and `pInfos`[i].`scratchData.hostAddress` + N - 1 must be valid host memory, where N is given by the `buildScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03726
  If `pInfos`[i].`mode` is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR`, all addresses between `pInfos`[i].`scratchData.hostAddress` and `pInfos`[i].`scratchData.hostAddress` + N - 1 must be valid host memory, where N is given by the `updateScratchSize` member of the VkAccelerationStructureBuildSizesInfoKHR structure returned from a call to vkGetAccelerationStructureBuildSizesKHR with an identical VkAccelerationStructureBuildGeometryInfoKHR structure and primitive count

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03771
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, `geometry.triangles.vertexData.hostAddress` must be a valid host address

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03772
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.indexType` is not `VK_INDEX_TYPE_NONE_KHR`, `geometry.triangles.indexData.hostAddress` must be a valid host address

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03773
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_TRIANGLES_KHR`, if `geometry.triangles.transformData.hostAddress` is not `0`, it must be a valid host address

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03774
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_AABBS_KHR`, `geometry.aabbs.data.hostAddress` must be a valid host address

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03775
  For each element of `pInfos`, the `buffer` used to create its `dstAccelerationStructure` member must be bound to memory that was not allocated with multiple instances

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03776
  For each element of `pInfos`, if its `mode` member is `VK_BUILD_ACCELERATION_STRUCTURE_MODE_UPDATE_KHR` the `buffer` used to create its `srcAccelerationStructure` member must be bound to memory that was not allocated with multiple instances

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03777
  For each element of `pInfos`, the `buffer` used to create each acceleration structure referenced by the `geometry.instances.data` member of any element of `pGeometries` or `ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` must be bound to memory that was not allocated with multiple instances

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03778
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, `geometry.instances.data.hostAddress` must be a valid host address

- VUID-vkBuildAccelerationStructuresKHR-pInfos-03779
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR`, each VkAccelerationStructureInstanceKHR::`accelerationStructureReference` value in `geometry.instances.data.hostAddress` must be a valid VkAccelerationStructureKHR object

- VUID-vkBuildAccelerationStructuresKHR-pInfos-04930
  For any element of `pInfos`[i].`pGeometries` or `pInfos`[i].`ppGeometries` with a `geometryType` of `VK_GEOMETRY_TYPE_INSTANCES_KHR` with `VK_BUILD_ACCELERATION_STRUCTURE_MOTION_BIT_NV` set, each `accelerationStructureReference` in any structure in VkAccelerationStructureMotionInstanceNV value in `geometry.instances.data.hostAddress` must be a valid VkAccelerationStructureKHR object

Valid Usage (Implicit)

- VUID-vkBuildAccelerationStructuresKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkBuildAccelerationStructuresKHR-deferredOperation-parameter
  If `deferredOperation` is not VK_NULL_HANDLE, `deferredOperation` must be a valid VkDeferredOperationKHR handle

- VUID-vkBuildAccelerationStructuresKHR-pInfos-parameter
  `pInfos` must be a valid pointer to an array of `infoCount` valid VkAccelerationStructureBuildGeometryInfoKHR structures

- VUID-vkBuildAccelerationStructuresKHR-ppBuildRangeInfos-parameter
  `ppBuildRangeInfos` must be a valid pointer to an array of `infoCount` VkAccelerationStructureBuildRangeInfoKHR structures

- VUID-vkBuildAccelerationStructuresKHR-infoCount-arraylength
  `infoCount` must be greater than `0`

- VUID-vkBuildAccelerationStructuresKHR-deferredOperation-parent
  If `deferredOperation` is a valid handle, it must have been created, allocated, or retrieved from `device`

Return Codes

Success

  - `VK_SUCCESS`

  - `VK_OPERATION_DEFERRED_KHR`

  - `VK_OPERATION_NOT_DEFERRED_KHR`

Failure

  - `VK_ERROR_OUT_OF_HOST_MEMORY`

  - `VK_ERROR_OUT_OF_DEVICE_MEMORY`

To copy or compact an acceleration structure on the host, call:

    // Provided by VK_KHR_acceleration_structure
    VkResult vkCopyAccelerationStructureKHR(
        VkDevice                                    device,
        VkDeferredOperationKHR                      deferredOperation,
        const VkCopyAccelerationStructureInfoKHR*   pInfo);

- `device` is the device which owns the acceleration structures.

- `deferredOperation` is an optional VkDeferredOperationKHR to request deferral for this command.

- `pInfo` is a pointer to a VkCopyAccelerationStructureInfoKHR structure defining the copy operation.

This command fulfills the same task as vkCmdCopyAccelerationStructureKHR but is executed by the host.

Valid Usage

- VUID-vkCopyAccelerationStructureKHR-accelerationStructureHostCommands-03582
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureHostCommands` feature must be enabled

- VUID-vkCopyAccelerationStructureKHR-deferredOperation-03678
  Any previous deferred operation that was associated with `deferredOperation` must be complete

- VUID-vkCopyAccelerationStructureKHR-buffer-03727
  The `buffer` used to create `pInfo->src` must be bound to host-visible device memory

- VUID-vkCopyAccelerationStructureKHR-buffer-03728
  The `buffer` used to create `pInfo->dst` must be bound to host-visible device memory

- VUID-vkCopyAccelerationStructureKHR-buffer-03780
  The `buffer` used to create `pInfo->src` must be bound to memory that was not allocated with multiple instances

- VUID-vkCopyAccelerationStructureKHR-buffer-03781
  The `buffer` used to create `pInfo->dst` must be bound to memory that was not allocated with multiple instances

Valid Usage (Implicit)

- VUID-vkCopyAccelerationStructureKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkCopyAccelerationStructureKHR-deferredOperation-parameter
  If `deferredOperation` is not VK_NULL_HANDLE, `deferredOperation` must be a valid VkDeferredOperationKHR handle

- VUID-vkCopyAccelerationStructureKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyAccelerationStructureInfoKHR structure

- VUID-vkCopyAccelerationStructureKHR-deferredOperation-parent
  If `deferredOperation` is a valid handle, it must have been created, allocated, or retrieved from `device`

Return Codes

Success

  - `VK_SUCCESS`

  - `VK_OPERATION_DEFERRED_KHR`

  - `VK_OPERATION_NOT_DEFERRED_KHR`

Failure

  - `VK_ERROR_OUT_OF_HOST_MEMORY`

  - `VK_ERROR_OUT_OF_DEVICE_MEMORY`

To copy host accessible memory to an acceleration structure, call:

    // Provided by VK_KHR_acceleration_structure
    VkResult vkCopyMemoryToAccelerationStructureKHR(
        VkDevice                                    device,
        VkDeferredOperationKHR                      deferredOperation,
        const VkCopyMemoryToAccelerationStructureInfoKHR* pInfo);

- `device` is the device which owns `pInfo->dst`.

- `deferredOperation` is an optional VkDeferredOperationKHR to request deferral for this command.

- `pInfo` is a pointer to a VkCopyMemoryToAccelerationStructureInfoKHR structure defining the copy operation.

This command fulfills the same task as vkCmdCopyMemoryToAccelerationStructureKHR but is executed by the host.

This command can accept acceleration structures produced by either vkCmdCopyAccelerationStructureToMemoryKHR or vkCopyAccelerationStructureToMemoryKHR.

Valid Usage

- VUID-vkCopyMemoryToAccelerationStructureKHR-accelerationStructureHostCommands-03583
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureHostCommands` feature must be enabled

- VUID-vkCopyMemoryToAccelerationStructureKHR-deferredOperation-03678
  Any previous deferred operation that was associated with `deferredOperation` must be complete

- VUID-vkCopyMemoryToAccelerationStructureKHR-pInfo-03729
  `pInfo->src.hostAddress` must be a valid host pointer

- VUID-vkCopyMemoryToAccelerationStructureKHR-pInfo-03750
  `pInfo->src.hostAddress` must be aligned to 16 bytes

- VUID-vkCopyMemoryToAccelerationStructureKHR-buffer-03730
  The `buffer` used to create `pInfo->dst` must be bound to host-visible device memory

- VUID-vkCopyMemoryToAccelerationStructureKHR-buffer-03782
  The `buffer` used to create `pInfo->dst` must be bound to memory that was not allocated with multiple instances

Valid Usage (Implicit)

- VUID-vkCopyMemoryToAccelerationStructureKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkCopyMemoryToAccelerationStructureKHR-deferredOperation-parameter
  If `deferredOperation` is not VK_NULL_HANDLE, `deferredOperation` must be a valid VkDeferredOperationKHR handle

- VUID-vkCopyMemoryToAccelerationStructureKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyMemoryToAccelerationStructureInfoKHR structure

- VUID-vkCopyMemoryToAccelerationStructureKHR-deferredOperation-parent
  If `deferredOperation` is a valid handle, it must have been created, allocated, or retrieved from `device`

Return Codes

Success

  - `VK_SUCCESS`

  - `VK_OPERATION_DEFERRED_KHR`

  - `VK_OPERATION_NOT_DEFERRED_KHR`

Failure

  - `VK_ERROR_OUT_OF_HOST_MEMORY`

  - `VK_ERROR_OUT_OF_DEVICE_MEMORY`

To copy an acceleration structure to host accessible memory, call:

    // Provided by VK_KHR_acceleration_structure
    VkResult vkCopyAccelerationStructureToMemoryKHR(
        VkDevice                                    device,
        VkDeferredOperationKHR                      deferredOperation,
        const VkCopyAccelerationStructureToMemoryInfoKHR* pInfo);

- `device` is the device which owns `pInfo->src`.

- `deferredOperation` is an optional VkDeferredOperationKHR to request deferral for this command.

- `pInfo` is a pointer to a VkCopyAccelerationStructureToMemoryInfoKHR structure defining the copy operation.

This command fulfills the same task as vkCmdCopyAccelerationStructureToMemoryKHR but is executed by the host.

This command produces the same results as vkCmdCopyAccelerationStructureToMemoryKHR, but writes its result directly to a host pointer, and is executed on the host rather than the device. The output may not necessarily be bit-for-bit identical, but it can be equally used by either vkCmdCopyMemoryToAccelerationStructureKHR or vkCopyMemoryToAccelerationStructureKHR.

Valid Usage

- VUID-vkCopyAccelerationStructureToMemoryKHR-accelerationStructureHostCommands-03584
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureHostCommands` feature must be enabled

- VUID-vkCopyAccelerationStructureToMemoryKHR-deferredOperation-03678
  Any previous deferred operation that was associated with `deferredOperation` must be complete

- VUID-vkCopyAccelerationStructureToMemoryKHR-buffer-03731
  The `buffer` used to create `pInfo->src` must be bound to host-visible device memory

- VUID-vkCopyAccelerationStructureToMemoryKHR-pInfo-03732
  `pInfo->dst.hostAddress` must be a valid host pointer

- VUID-vkCopyAccelerationStructureToMemoryKHR-pInfo-03751
  `pInfo->dst.hostAddress` must be aligned to 16 bytes

- VUID-vkCopyAccelerationStructureToMemoryKHR-buffer-03783
  The `buffer` used to create `pInfo->src` must be bound to memory that was not allocated with multiple instances

Valid Usage (Implicit)

- VUID-vkCopyAccelerationStructureToMemoryKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkCopyAccelerationStructureToMemoryKHR-deferredOperation-parameter
  If `deferredOperation` is not VK_NULL_HANDLE, `deferredOperation` must be a valid VkDeferredOperationKHR handle

- VUID-vkCopyAccelerationStructureToMemoryKHR-pInfo-parameter
  `pInfo` must be a valid pointer to a valid VkCopyAccelerationStructureToMemoryInfoKHR structure

- VUID-vkCopyAccelerationStructureToMemoryKHR-deferredOperation-parent
  If `deferredOperation` is a valid handle, it must have been created, allocated, or retrieved from `device`

Return Codes

Success

  - `VK_SUCCESS`

  - `VK_OPERATION_DEFERRED_KHR`

  - `VK_OPERATION_NOT_DEFERRED_KHR`

Failure

  - `VK_ERROR_OUT_OF_HOST_MEMORY`

  - `VK_ERROR_OUT_OF_DEVICE_MEMORY`

To query acceleration structure size parameters on the host, call:

    // Provided by VK_KHR_acceleration_structure
    VkResult vkWriteAccelerationStructuresPropertiesKHR(
        VkDevice                                    device,
        uint32_t                                    accelerationStructureCount,
        const VkAccelerationStructureKHR*           pAccelerationStructures,
        VkQueryType                                 queryType,
        size_t                                      dataSize,
        void*                                       pData,
        size_t                                      stride);

- `device` is the device which owns the acceleration structures in `pAccelerationStructures`.

- `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 property to be queried.

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

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

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

This command fulfills the same task as vkCmdWriteAccelerationStructuresPropertiesKHR but is executed by the host.

Valid Usage

- VUID-vkWriteAccelerationStructuresPropertiesKHR-accelerationStructureHostCommands-03585
  The `VkPhysicalDeviceAccelerationStructureFeaturesKHR`::`accelerationStructureHostCommands` feature must be enabled

- VUID-vkWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-04964
  All acceleration structures in `pAccelerationStructures` must have been built prior to the execution of this command

- VUID-vkWriteAccelerationStructuresPropertiesKHR-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-vkWriteAccelerationStructuresPropertiesKHR-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`

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-03448
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR`, then `stride` must be a multiple of the size of VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-03449
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_COMPACTED_SIZE_KHR`, then `pData` must point to a VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-03450
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR`, then `stride` must be a multiple of the size of VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-03451
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_SIZE_KHR`, then `pData` must point to a VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-06731
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SIZE_KHR`, then `stride` must be a multiple of the size of VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-06732
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SIZE_KHR`, then `pData` must point to a VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-06733
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_BOTTOM_LEVEL_POINTERS_KHR`, then `stride` must be a multiple of the size of VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-06734
  If `queryType` is `VK_QUERY_TYPE_ACCELERATION_STRUCTURE_SERIALIZATION_BOTTOM_LEVEL_POINTERS_KHR`, then `pData` must point to a VkDeviceSize

- VUID-vkWriteAccelerationStructuresPropertiesKHR-dataSize-03452
  `dataSize` must be greater than or equal to `accelerationStructureCount`*`stride`

- VUID-vkWriteAccelerationStructuresPropertiesKHR-buffer-03733
  The `buffer` used to create each acceleration structure in `pAccelerationStructures` must be bound to host-visible device memory

- VUID-vkWriteAccelerationStructuresPropertiesKHR-buffer-03784
  The `buffer` used to create each acceleration structure in `pAccelerationStructures` must be bound to memory that was not allocated with multiple instances

Valid Usage (Implicit)

- VUID-vkWriteAccelerationStructuresPropertiesKHR-device-parameter
  `device` must be a valid VkDevice handle

- VUID-vkWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-parameter
  `pAccelerationStructures` must be a valid pointer to an array of `accelerationStructureCount` valid VkAccelerationStructureKHR handles

- VUID-vkWriteAccelerationStructuresPropertiesKHR-queryType-parameter
  `queryType` must be a valid VkQueryType value

- VUID-vkWriteAccelerationStructuresPropertiesKHR-pData-parameter
  `pData` must be a valid pointer to an array of `dataSize` bytes

- VUID-vkWriteAccelerationStructuresPropertiesKHR-accelerationStructureCount-arraylength
  `accelerationStructureCount` must be greater than `0`

- VUID-vkWriteAccelerationStructuresPropertiesKHR-dataSize-arraylength
  `dataSize` must be greater than `0`

- VUID-vkWriteAccelerationStructuresPropertiesKHR-pAccelerationStructures-parent
  Each element of `pAccelerationStructures` must have been created, allocated, or retrieved from `device`

Return Codes

Success

  - `VK_SUCCESS`

Failure

  - `VK_ERROR_OUT_OF_HOST_MEMORY`

  - `VK_ERROR_OUT_OF_DEVICE_MEMORY`