M4.02

Changelog

All notable changes to libslang-vk — a C++23 Vulkan runner for libretro
slang shader presets — are documented in this file.

Milestones follow the M-series plan in PLAN.md §11 (M0 → M5).
Each milestone corresponds to the matching M* commit(s) on main (no git
tags yet). Format adapted from
Keep a Changelog.

Unreleased

Planned

• Remaining 91 corpus failures (out of 2658 presets at the pinned corpus rev),
  all one class: sampled-but-unbound textures behind preprocessor dead code —
  ReflectionPass in MBZ NO-REFLECT variants (~60), ambi_temporal_pass
  uborder (~15), play nedi (~9). Next fix: run the texture-reference check
  against preprocessed text instead of raw source.
• M3 leftovers: golden-image conformance suite, perf budgets.
• M5 (1.0): API freeze, packaging, docs/API.md.

M4.02 — 2026-10-18

Corpus rescan release: full-corpus verdict went from 826 LOAD / 1832 FAIL
(2026-10-17 baseline) to 2567 LOAD / 91 FAIL — zero regressions at the
pinned revision.

Fixed

• #reference merge rebase stored cwd-relative paths (RebaseReferenceFilePath()
  in src/core/preset_parser.cpp): when the scan root was relative (the
  documented corpus_sweep slang-shaders invocation), rebased pass/texture
  paths were joined onto the importing preset's directory at load time,
  producing garbled paths and failing ~700 otherwise-healthy presets. Rebased
  paths are now absolutized inside the SEC-01 shader root. Regression test in
  tests/test_preset_parser.cpp (relative root + #reference chdir fixture
  asserts an absolute, existing merged path).

Added

• corpus_sweep --only-from FILE whitelist for chunked rescans (keeps
  corpus-root semantics; enables full-corpus sweeps in sandboxed/short-lived
  environments).
• CI: the Windows shader-demo artifact now bundles corpus_sweep.exe (Linux
  ships corpus_sweep), with an updated USAGE.txt section showing the
  absolute-root invocation.
• .github/workflows/corpus.yml workflow_dispatch can regenerate the ledger
  without any local binary.

Changed

• corpus/baseline-ledger.txt refreshed at the same corpus rev: 2658 presets
  → 2567 LOAD / 91 FAIL, 0 regressions, +1741 improved (bezel +1367,
  presets +160, hdr +146, crt +32, ...). Added/gone: 0/0.

M4.01 — 2026-10-18

Fixed

• slang: unknown texture reference 'PhosphorPassFeedback' on presets
  whose passes are named only via #pragma name (no aliasN — e.g.
  crt-yah.slangp): the translator's texture-name universe only knew LUT
  names, aliasN and User#, while the chain runtime already resolved pragma
  names, Feedback-suffix taps and <name>Size. Pass names from
  #pragma name are now collected at load time and seeded into the universe,
  so bare-name taps, previous-frame <name>Feedback taps and <name>Size
  UBO members all bind.

Added

• Public API slv::preset::CollectSlangPragmaNames(shaderPath, out)
  (include/slangvk/core/slang_translate.hpp): soft-fail include-once scan
  with the same ResolveIncludes bucketing as TranslateSlang; scan failure
  is silent and real errors surface from per-pass translation.

Tests

• Four feedback-tap regressions in tests/test_slang_translate.cpp: collector
  finds the pragma name; seeded universe binds PhosphorPassFeedback in set 2;
  lowercase spelling resolves; empty universe still hard-fails with the
  original diagnostic.

M4 — 2026-10-17/18

DevilutionX presentation spike (plan §8 mode (a)) plus the shader_demo
example app and its first two real-world fix waves.

Added

• examples/shader_demo: hybrid windowed/headless demo — GLFW backend
  probing with headless-only fallback, TUI preset browser, animated-pattern +
  image inputs, PNG frame writer, and a --headless --no-menu --frames N --out DIR sweep mode used for corpus verification (~2k lines across
  shader_demo.cpp, window_target.hpp, input_source.hpp,
  preset_browser.hpp, frame_writer.hpp).
• Default input: bundled assets/testcard.png (480×320 pixel-art
  Goku/Mario/Luigi, generated by tools/make_testcard.py + tools/sprites/),
  with a 5-level portable asset lookup starting at the executable's directory.
• Corpus tooling: corpus/baseline-ledger.txt (per-preset LOAD/FAIL
  baseline) + .github/workflows/corpus.yml — nightly pinned-rev sweep with a
  no-regression gate.
• Runner presentation: SwapchainFrame with letterbox and rotation;
  push-block / size-param runner coverage (test_runner_m4.cpp,
  test_runner_pushblock.cpp, sizeparam/pushfrag golden shaders).
• docs/CHECKLIST.md, tools/scan_codefindings.py, vendored
  stb_image_write.h; README CI badge + screenshot.

Fixed

• crt-consumer.slangp black screen: UBO member parsing stripped smooth
  from float smoothness; via a left-token match, leaving member ness
  zero-initialized and the corner mask at 0. Added a right-token-boundary
  check plus a SLANGVK_FILL_DEBUG block-fill dump in chain.cpp, with a
  byte-exact golden regression (tests/data/runner/smoothqual.*).
• analog-service-menu.slangp include target outside the shaders root:
  the SEC-01 ancestor-retry now also fires on that error string (previously
  only on cannot-open).
• shader_demo defaulted to the animated pattern (characters never visible);
  it now defaults to the testcard image and falls back only if the asset is
  missing.

M3 — 2026-10-17

Conformance + perf wave (partial per PLAN.md §11).

Added

• src/vk/lut.cpp: LUT texture upload paths (plain, mipmap, <texture>Size
  user bindings), golden runner3 presets (lut, lut_mip, lut_size,
  lut_user + PNG fixtures).
• examples/corpus_sweep.cpp: batch load/render sweep over a preset tree —
  the basis of the corpus baseline ledger.
• Chain/images/device hardening (+~350 lines) and parser fixes; CI updates.

M2 — 2026-10-17

Added

• Chain semantics on the Vulkan runner, proven by the test_runner_m2
  canary suite: feedback ping-pong (previous-frame output), history ring taps
  (OriginalHistory1/3), pass formats (default/float/srgb), include/cycle
  resolution, mipmap refill (textureLod), FBO + history-ring recreation on
  input-size change, live setParameter(), validation-error gating, and a
  negative control (PassOutput0 self-read must fail LOAD).

M1 — 2026-10-17

Added

• Vulkan runner skeleton (src/vk/ — device.cpp, images.cpp, preset.cpp,
  chain.cpp + VMA): headless golden blit on lavapipe with zero validation
  errors; runner test presets (blit, param).

Fixed

• MSVC build fix; MinGW64 CI matrix additions (libslangvk.dll / .a
  artifacts).

M0 — 2026-10-17

Added

• Scaffold: core trio ported clean — preset parser, slang→GLSL translator,
  slang compiler glue (src/core/, include/slangvk/); 12/12 tests green;
  field-preset round-trip fixtures (feedback / history / format / include
  cycles).
• CI: Linux tests on lavapipe + asan/ubsan build; Windows MinGW
  libslangvk.dll / .a artifacts; vendored CMake deps.
• Docs: PLAN.md (architecture + milestones), SPEC.md (libretro slang
  preset conformance scope), PROVENANCE.md (MIT + upstream ledger).

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