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Build the NextGen data model from refactored + aggregated layers (nextgen phase)

Source: R/build_nextgen.R
nextgen_fabric.Rd

Consumes stage-1 (refactored + reconciled + hydrolocations) AND stage-2 (out_vpu{id}.gpkg) artifacts; produces the ngen-ready GeoPackage with model attributes and aspatial network.

Usage

nextgen_fabric(
  vpuid,
  fabric_dir,
  fdr_path,
  fac_path,
  fallback_fdr_path = NULL,
  fallback_fac_path = NULL,
  out_dir,
  coverage_min = 0.9,
  threshold_m2 = 1000,
  threshold_sqkm = 0.001,
  gap_fill_area = 1000,
  overlap_rule = "max-area",
  n_cores = NULL,
  hydraulics_path = NULL,
  lakes_path = NULL,
  lake_mask_path = NULL,
  slope_parquet = NULL,
  reference_gpkg = NULL,
  verbose = FALSE
)

Arguments

vpuid

VPU identifier.

fabric_dir

Path to the vpu working directory holding the refactored + aggregated fabric.

fdr_path, fac_path

Raster paths (local or /vsis3/...).

fallback_fdr_path, fallback_fac_path

Optional paths to a fallback FDR/FAC pair used when the primary returns NA. NULL disables the fallback (default). Ignored when equal to the primary paths.

out_dir

Parent output directory; vpu_{vpuid}/ is created.

coverage_min

Divide-coverage invariant + coalesce/clip floor (0-1).

threshold_m2

fill_small_holes area threshold on ngen divides (m^2).

threshold_sqkm

prune_ghost_divides area threshold (km^2).

gap_fill_area

Gap-fill area for hfutils::clean_gpkg_layer (ngen phase).

overlap_rule

Divide overlap resolution rule.

n_cores

Worker count for repair_split_divides_at_pois.

hydraulics_path

Optional path to a RiverML channel table parquet, either its v2 output (e.g. superconus_ml_attributes_v2.parquet) or the earlier channel-geometry table. When supplied, Step 6g computes flow attributes for both flowpath_id and flowline_id and writes flowpath-attributes and flowline-attributes layers to the ngen GeoPackage. Reaches with no match in the table fall back through a geomorphic proxy. NULL skips Step 6g (default).

lakes_path

Optional path to the NWM lakes GeoPackage (e.g. nwm_lakes.gpkg). When supplied, Step 6h identifies the outlet flowline of each lake (minimum flowline_hydroseq among COMIDs belonging to the lake), joins NWM lake attributes, and writes a lakes layer to the ngen GeoPackage. The reach -> lake_id membership used for outlet fallback and member stamping comes from lake_mask_path. NULL skips Step 6h (default).

lake_mask_path

Optional path to a lake-mask parquet: reach -> waterbody membership with integer columns comid (reference flowline id) and wbareacomi (waterbody / lake_id). Required when lakes_path is supplied. The CONUS mask is materialized from NHDPlusV2 wbareacomi; oCONUS / superconus domains supply an equivalent with the same schema.

slope_parquet

Optional path to a per-reference-id slope parquet, passed to finalize_data_model(). NULL (default) takes slope from hydraulics_path when that table carries a slope_m_m column, and otherwise leaves slope NA.

reference_gpkg

Optional path to the reference fabric GeoPackage (source of member slope / divide geometry). NULL disables features needing it.

verbose

Propagated to internal helpers.

Value

Invisibly, a list with files, timings, invariants.

Details

ngen_vpu{id}.gpkg writes to {out_dir}/vpu_{vpuid}/; all other files write to {out_dir}/vpu_{vpuid}/work/:

  • ngen_vpu{id}.gpkg: layers: flowpaths, divides, nexus, plus aspatial network and model-attribute layers

  • timings.json, invariants.json

Examples

if (FALSE) { # \dontrun{
nextgen_fabric(vpuid      = "01",
               fabric_dir = "out/vpu_01",
               fdr_path   = "fdr.tif",
               fac_path   = "fac.tif",
               out_dir    = "out",
               coverage_min = 0.95)
} # }