VkAccelerationStructureTrianglesDisplacementMicromapNV

The VkAccelerationStructureTrianglesDisplacementMicromapNV structure is defined as:

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.