SimSat v0.2.0 - natural IR, two-subcolumn clouds, and cleaner top-down lighting

SimSat v0.2.0

This release focuses on more natural infrared presentation, better low-sun terrain, faster reviewed cloud closure, and cleaner top-down shadows.

Highlights

• Natural IR is now Recommended. Band 13 defaults to NOAA's continuous heritage grayscale, avoiding the solid red blobs and isotherm rings created by the former default false-color curve. The underlying floating-point Kelvin field is unchanged.
• Legacy IR analysis palettes remain available. CIMSS, BD, AVN, Funktop, Rainbow, and legacy linear grayscale are still selectable in Studio, the CLI, and Python.
• Recommended clouds use deterministic two-subcolumn closure. This keeps more wispy/fractional structure than effective-OD while being much faster than the higher-member convergence references. Effective-OD and deterministic 4/8/16 remain explicit choices. Deterministic-2 can roughly double the cloud-march portion of CPU render time versus effective-OD.
• Improved low-sun visible terrain. The bounded land solar-zenith recovery has a more useful gain range, with exact per-pixel solar-elevation diagnostics and temporal QA.
• Cleaner top-down lighting. Cloud-front atmosphere is restored and top-down ground cloud shadows receive a display-only antialiasing pass; geostationary and raw reflectance products are not filtered.
• Optional surface experiment. The post-light terrain toe is exposed across Rust, CLI, Python, and Studio, but remains default-off.
• Consistent controls. Natural IR, the legacy palettes, cloud closure, shadow antialiasing, and the reviewed settings are available through the supported interfaces.

Validation

• Owner-tested Windows RC2, including live IR re-enhancement and IR/WV Recommended transitions.
• HRRR and NSSL top-down/geostationary cross-case checks; Natural versus legacy enhancement produced byte-identical raw Kelvin fields.
• Public CI: https://github.com/FahrenheitResearch/simsat/actions/runs/29215685042
• Release artifact build: https://github.com/FahrenheitResearch/simsat/actions/runs/29215402872
• Exact manylinux wheel installed and rendered a generated 12 x 12 Band-13 scene in WSL.
• Both Linux CLI binaries passed --help smoke tests; tar entries are executable mode 755.

Downloads

• simsat-studio-v0.2.0-windows-x86_64.exe
  SHA-256: 6509369B3C269B2DC2F74FE3E372290D0312178A2C80A9A521A4E3B74F0E8328
• simsat-0.2.0-cp38-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl
  SHA-256: 3C50CA103311555D7BFBCEDDFF4D1ACE20EC151A2AB75F819B915417DBCE7682
• simsat-cli-v0.2.0-linux-x86_64.tar.gz
  SHA-256: 2EC69FBC24BD962BE554C0B1137BE96C8E5322E65C17CDA480E077C77C3F5F9C
• THIRD-PARTY-NOTICES.txt
  SHA-256: E235FA33875603FE529DED887E6FD2CF4C595B7F486CE57567E3E4CED6C6C036

Windows note

The Windows executable is a self-contained static-CRT build. It is currently unsigned, so Microsoft Defender SmartScreen may show an unknown-publisher warning.