Review locally available coordinate operation candidates

terrain_transform_candidates(
  source_crs,
  target_crs,
  aoi,
  source_epoch = NULL,
  target_epoch = NULL
)

Arguments

source_crs, target_crs: Full source and target CRS definitions.
aoi: Longitude/latitude bounds: west, south, east, north.
source_epoch, target_epoch: Known coordinate epochs, or NULL when unknown.

Value

A serializable catalog with exact pipelines, grid evidence, reference definitions and software/database identity. No operation is selected or run.

Details

Uses PROJ candidate discovery with strict area containment and local grid availability. Missing grids, ballpark operations and epoch-dependent operations are retained with explanations but are not selectable. Available candidates are plans, not qualification of DEM execution. Complete combined horizontal/vertical pipelines are retained. No resources are downloaded.