Crate ras_commander_fast_map 

Native 2D flood inundation mapping: horizontal, sloping, and ras2fim-2D Step05.

Extends the immutable baseline prototype prototype/kernel (RasMapper_Stored_Maps_Rust, 2026-10-22, CLB Engineering): the barycentric evaluation, the 100 * DBL_EPSILON inclusion test and the lowest-simplex-id tie rule are copied from that kernel. Upstream algorithm: Andy Carter, PE / University of Texas at Austin, ras2fim-2d 3146f647, Step05 (BSD-3-Clause).

The application uses step05, which preserves the upstream float32 sequence and native approximate reprojection over supplied SciPy transforms and axes. The older session diagnostic retains its distinct f64 arithmetic. Step05 and triangulated-session scope boundaries:

• Interpolation topology is always caller-supplied global SciPy/Qhull simplices. There is no native triangulation and never a per-AOI or per-tile retriangulation.
• Wet masks and sample preparation are caller-supplied (upstream/Python adapters).
• Native terrain is same-CRS, north-up, single-band float32 GeoTIFF read through terrio with an explicit sampling formula. Other terrain types require separate qualification.
• The diagnostic session’s f64 arithmetic does not replace the Step05 float32 sequence.

Independent horizontal and sloping_session methods prepare pixel ownership directly from cell polygons. Plain sloping reconstructs hydraulic connectivity and corner interpolation rather than using the Step05 SciPy topology.

Modules

aoi

Crop-invariant AOI coverage. Hydraulic cell ownership still uses terrio.

boundary_contour

Deterministic zero-depth contours. No claim of native vector parity. Terrain sampling/surface reconstruction and AOI halos belong to the caller.

boundary_session

Deterministic signed-depth boundary pipeline. Raster delivery is untouched.

cache

Shared, immutable, byte-bounded decoded-tile cache with single-flight loading.

horizontal

Horizontal cell-constant mapping. Caller supplies deterministic pixel ownership; native terrain is decoded once for the constrained window and reused across profiles. No triangulation, resampling, per-pixel cache lock, or GDAL dependency.

interp

Prepared, reusable interpolator over caller-supplied global simplices.

model

Request schema, validation and profile-source loading.

ownership

Terrio ownership on an exact admitted grid. Input polygons are validated by the caller.

scipy_interp

Exact port of SciPy’s 2-D LinearNDInterpolator evaluation over a caller-supplied Delaunay.

session

Prepared multi-profile / multi-AOI session.

sink

Deterministic streaming directory sink with failure-safe unit commits.

sloping

Experimental sloping reconstruction. Native qualification is stage-specific.

sloping_session

Explicit sloping batch path with independently selected native rendering controls. Geometry, terrain and ownership are shared across profiles; hydraulic connectivity is reconstructed for every profile.

step05

Upstream ras2fim-2D Step05 raster-compatibility stages over prepared global inputs.

terrain

Native same-CRS north-up GeoTIFF terrain through terrio 0.4.2 lazy reads.

terrain_scope

Mapping on the top-priority source of a multi-source terrain, without a RAS Mapper terrain export (top-priority-source-footprint/1).

velocity

Research kernel: RAS Mapper velocity reconstruction (rasmapper-sloping-velocity/0).

whole_simulation

Whole-simulation stored-map products: arrival time, duration and percent time inundated (native-whole-simulation-horizontal/1).

Enums

MapError

Errors are typed so callers can distinguish invalid input, budgets and unsupported cases.

Constants

CONTRACT_VERSION

Identifies the output/failure/budget contract (not the numerical method, which is unchanged).

ENGINE_COMMIT

Source revision of an official build, or unknown for an unversioned archive.

ENGINE_VERSION

Version of the standalone crate and Python wheel.

METHOD_VERSION

Identifies the method semantics. Changing any recorded convention must change this string.

Functions

method_record

Static description of the implemented semantics, emitted in every report.