# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [0.1.2] - 2026-03-05

### Fixed

- **ORVS citation corrected** — TR number changed from TR-186-2-02-11 (a
  different report) to TR-186-2-01-10; year corrected from 2002 to 2001.
  Also fixed in `signal.py` docstring.
- **Abstract rewritten** — Removed "memory is linear, pixels are square,
  voxels are cubic" (rhetorical-as-factual). Replaced with research framing.
- **Causal overclaims softened** — "sole variable," "entirely attributable,"
  and "only variable" replaced with language acknowledging node-count
  mismatch. "Unexamined default" → "widely adopted default." "Failure mode"
  → "axis-alignment artifact."
- **FCC/HCP consistency** — Introduction and conclusion now both include
  HCP alongside FCC for densest sphere packing claim.
- **Intro genealogy tightened** — "descends from Descartes... through von
  Neumann" → "aligns with Cartesian analytic geometry... and stored-program
  architecture designs."
- **Conclusion rhetorical softening** — "not because it was chosen but
  because it was inherited" → "largely through convention rather than
  demonstrated optimality."
- **Projection method justification** — Added one-sentence explanations
  for why Rung 4 uses random projection and ANN index uses PCA.
- **Full git SHA** — Reproducibility paragraph now uses full 40-character
  commit hash instead of abbreviated 7-character prefix.

## [0.1.1] - 2026-03-05

### Fixed

- **BCC/FCC sampling theory framing** — Correctly attribute 3D sampling
  optimality to BCC (not FCC) per the volume-rendering literature. Rung 3
  results reframed as direct empirical measurements, not derivations from
  Petersen-Middleton theory. Clarified dual-lattice relationship (FCC ↔ BCC
  are reciprocal duals). Fixed `signal.py` docstring: rhombic dodecahedron
  is the real-space Voronoi cell, not the Nyquist region.
- **Kepler conjecture timeline** — Announced 1998, published 2005, formally
  verified 2014–2017. Both FCC and HCP achieve maximal packing density.
- **Bibliography metadata** — Corrected years and DOIs for Theußl (2000),
  Entezari (2004), and Csebfalvi (2010).
- **Universal claims scoped** — "Scale-invariant" → "stable across tested
  scales." "Not optimal" scoped to isotropic, propagation-dominated workloads.
  Applied consistently across all 16 affected files.

### Added

- Reproducibility paragraph in paper (§3): seed, trial count, commit hash
- Node-matching notation: explicit formulas for n_SC and n_FCC
- "When the Cubic Lattice Wins" subsection in paper
- Expanded "Limitations and Threats to Validity" section

### Changed

- Paper §4 title: "Context Architecture" → "Embedding Neighborhood Preservation"

## [0.1.0] - 2026-03-04

### Added

- **Rung 0: Lattice Library** — `CubicLattice` and `FCCLattice` classes with
  matched node counts, interior degree verification, and NetworkX export
- **Rung 1: Graph Theory** — average shortest path, diameter, algebraic
  connectivity, and clustering coefficient benchmarks across three scales
- **Rung 2: Spatial Operations** — flood fill, nearest-neighbor queries,
  range queries, and locality-sensitive hashing benchmarks
- **Rung 3: Signal Processing** — 3D bandlimited signal reconstruction MSE
  and directional isotropy analysis (direct empirical measurement)
- **Rung 4: Context Architecture** — embedding neighbor recall, information
  diffusion rate, and consensus convergence benchmarks
- **Rung 5: Synthesis** — "The Shape of the Cell" complete synthesis document
  with cultural genealogy, cybernetic interpretation, and recommendations
- Visualization module with Vadrashinetal color palette
- Banner generation from library code (`scripts/generate_banner.py`)
- CI workflow (Python 3.10, 3.11, 3.12) with benchmark reproduction
- Security scanning (gitleaks)
- Full community health files (CONTRIBUTING, CODE_OF_CONDUCT, SECURITY)

### Key Results

| Metric | FCC vs Cubic |
|--------|-------------|
| Average shortest path | 30% shorter |
| Graph diameter | 40% smaller |
| Algebraic connectivity | 2.4x higher |
| Flood fill reach | 55% more nodes |
| Signal reconstruction MSE | 5-10x lower |
| Embedding neighbor recall | +15-26pp at 1-hop |
| Edge cost | ~2x more edges |

[0.1.2]: https://github.com/promptcrafted/rhombic/releases/tag/v0.1.2
[0.1.1]: https://github.com/promptcrafted/rhombic/releases/tag/v0.1.1
[0.1.0]: https://github.com/promptcrafted/rhombic/releases/tag/v0.1.0
