D3D12_RAYTRACING_ACCELERATION_STRUCTURE_POSTBUILD_INFO_COMPACTED_SIZE_DESC structure (d3d12.h)

Describes the space requirement for acceleration structure after compaction.

Syntax

typedef struct D3D12_RAYTRACING_ACCELERATION_STRUCTURE_POSTBUILD_INFO_COMPACTED_SIZE_DESC {
  UINT64 CompactedSizeInBytes;
} D3D12_RAYTRACING_ACCELERATION_STRUCTURE_POSTBUILD_INFO_COMPACTED_SIZE_DESC;

Members

CompactedSizeInBytes

The space requirement for acceleration structure after compaction.

It is guaranteed that a compacted acceleration structure doesn’t consume more space than a non-compacted acceleration structure.

Pre-compaction, it is guaranteed that the size requirements reported by GetRaytracingAccelerationStructurePrebuildInfo for a given build configuration (triangle counts etc.) will be sufficient to store any acceleration structure whose build inputs are reduced (e.g. reducing triangle counts). This non-increasing property for smaller builds does not apply post-compaction, however. In other words, it is not guaranteed that having fewer items in an acceleration structure means it compresses to a smaller size than compressing an acceleration structure with more items.

Requirements