This week’s update is entirely focused on the continued development and performance benchmarking of the lustre_voxel library. The priority was bringing block caching performance into sub-nanosecond territory while adhering strictly to Data-Oriented Design (DOD) and Data-Oriented Programming (DOP) standards.

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A major focus was comparative benchmarking between sequential and parallel block registry access for cache efficiency.

Three test passes were conducted:

1. Initial Reference (Old Parallel):

   • 85 blocks, 17.239 µs total average = 202.81 ns/block

2. New Sequential Test (4096 blocks):

   • 3.0044 µs total average = ~0.734 ns/block
   • ✅ Sub-nanosecond goal achieved

3. New Parallel Test (4096 blocks):

   • 53.787 µs total average = ~13.13 ns/block

The results confirmed that:

• Sequential access is significantly more efficient for tight inner loops, with ~17x better per-block performance than the parallel path.
• Parallel access is only beneficial for high-cost operations across multiple chunks, such as world generation, terrain meshing, or IO-bound streaming.

These findings will inform chunk processing strategies in lustre_voxel, where sequential will be used for intra-chunk systems, and parallelism will be reserved for larger spatial operations.

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The submodules blocks, chunks, and data were repeatedly refactored this week to align with DOD principles:

• ✅ Block types are now stored as Vec<u16> for cache-friendly access
• ✅ Metadata is sparsely packed with bit-level precision, minimizing overhead for blocks like SEA_LEVEL_AIR
• ✅ Block registries use static lookup tables for property access, preventing dynamic allocation during runtime

The current prototype supports block IDs 0–85, which are exclusively used for world builder blocks:

• Terrain Blocks
• Atmosphere Blocks
• Resource Blocks
• Fluid Blocks

This block set is foundational for generating layered planetary environments (core → mantle → crust → ocean → atmosphere) with biome and sub-biome diversity.

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• All systems in lustre_voxel are being rewritten to align with DOD/DOP.
• Profiling data is being used to enforce a hard performance ceiling of <1 ns/block access in critical systems.
• A micro-benchmark was completed this week to evaluate sequential (SoA-like) vs parallel (AoS-like) access for block cache lookups.
• A full ECS-scale simulation at biome scale (394³ chunks, ~250B blocks) is still being planned to evaluate SoA vs AoS at the system level.

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• Integrate DOD-Compliant Block Registry

  • Finalize BlockTypeRegistry for static lookup tables
  • Implement fast-path cache hints for hot blocks (terrain, stone, air)

• Begin Work on biomes Submodule

  • Expand biome types and define sub-biomes (e.g., coastal, alpine, volcanic)
  • Integrate biome rulesets for terrain, fluid, resource, and atmosphere layering
  • Optimize data layout for deterministic access and cache locality

• Begin Work on generators Submodule

  • Refine procedural generation logic for planetary and lunar chunks
  • Implement biome-aware generation paths using precomputed noise fields
  • Benchmark sequential vs parallel generation to identify optimal workload strategy

• Begin Work on mesh Submodule

  • Establish baseline greedy mesher for surface mesh extraction
  • Prepare chunk meshing pipeline for integration with lustre_render
  • Validate meshing performance against block cache access benchmarks

Stay tuned for next week as we continue focusing on performant and optimized code early. We'll be conducting a full ECS-scale simulation at biome scale (394³ chunks, ~250B blocks) to evaluate SoA vs AoS at the system level.