OpenUSD v26.08 usdAbc declares supportsEditing false, documents that FaceSet, NuPatch and Light are not translated and component ops are flattened to a 4x4 matrix, and its reader scales Alembic seconds by a default of 24 time codes per second unless metadata supplies another...

OpenUSD v26.08 usdAbc declares supportsEditing false, documents that FaceSet, NuPatch and Light are not translated and component ops are flattened to a 4x4 matrix, and its reader scales Alembic seconds by a default of 24 time codes per second unless metadata supplies another value. Curator correction 2026-10-23 (discovery audit record C3-B684-02; sources re-fetched 2026-10-23, excerpts re-located by curator GET): Problem. Candidate M2-02 says OpenUSD tests Alembic 1.8.5 (VERSIONS.md L31) and that build_usd.py builds 1.8.5, 'seven releases behind 1.8.12'. Nature: (e) changed since. Conditions. Applies to OpenUSD v26.11.1 (published 2026-10-21) and later. Method. At tag v26.11.1 VERSIONS.md lists Alembic 1.8.10 in all three columns and build_usd.py downloads the 1.8.10 tag, so the gap to Alembic 1.8.12 is two releases (1.8.11 and 1.8.12), not seven. At v26.08 the same files say 1.8.5 (candidate was right for that tag). Failure modes. A reader trusting the old figure would overstate how far OpenUSD's tested Alembic lags behind current releases. Limitations. The HDF5-off build flag was not re-read at v26.11.1. Version and date. Fetched 2026-10-23. Curator qualifications: Build flags, HDF5 support, exact mapping table, curve-basis collapse, abcReRoot/abcLayers arguments and version-identity diff (F0, F2, F3, F6-F8) not reinspected; DCC FPS hint path not re-read. Static reading only; no USD build, no Alembic read. Limitations: Static reading only; no USD build, no Alembic read. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://github.com/PixarAnimationStudios/OpenUSD/tree/ee47c679abde5b467a7b6a41f3b2285564a4222e/pxr/usd/plugin/usdAbc",
      "note": "pxr/usd/plugin/usdAbc/plugInfo.json lines 11-17; docs/plugins_alembic.rst lines 58-67; alembicReader.cpp lines 832, 879, 1020-1027"
    },
    {
      "url": "https://raw.githubusercontent.com/PixarAnimationStudios/OpenUSD/v26.11.1/VERSIONS.md",
      "note": "correction source (record C3-B684-02): VERSIONS.md Alembic row; build_usd.py ALEMBIC_URL; VERSIONS.md Alembic row at v26.08; release titles"
    },
    {
      "url": "https://raw.githubusercontent.com/PixarAnimationStudios/OpenUSD/v26.11.1/build_scripts/build_usd.py",
      "note": "correction source (record C3-B684-02): VERSIONS.md Alembic row; build_usd.py ALEMBIC_URL; VERSIONS.md Alembic row at v26.08; release titles"
    },
    {
      "url": "https://raw.githubusercontent.com/PixarAnimationStudios/OpenUSD/ee47c679abde5b467a7b6a41f3b2285564a4222e/VERSIONS.md",
      "note": "correction source (record C3-B684-02): VERSIONS.md Alembic row; build_usd.py ALEMBIC_URL; VERSIONS.md Alembic row at v26.08; release titles"
    },
    {
      "url": "https://github.com/alembic/alembic/releases.atom",
      "note": "correction source (record C3-B684-02): VERSIONS.md Alembic row; build_usd.py ALEMBIC_URL; VERSIONS.md Alembic row at v26.08; release titles"
    }
  ]
}