Glossary#

This glossary collects definitions for project-specific terminology and supporting technologies referenced throughout the reVRt documentation.

barrier layer#: Weighted raster dataset that stores cells where routing is blocked or strongly penalized. reVRt writes the combined barriers to the transmission_barrier dataset inside the routing file.
barrier multiplier#: Scalar applied to raw barrier rasters before they are merged with friction values. The multiplier is configured through MergeFrictionBarriers and controls how restrictive obstacles become in the combined layer.
cell size#: The ground distance represented by one raster pixel, usually expressed in meters. Cell size is derived from the affine transform stored with each dataset and is used when converting per-mile cost inputs to per-cell values.
cost layer#: Individual raster derived from source GeoTIFFs, vector data, or global values that contributes to the total routing cost surface. Cost layers are configured with LayerBuildConfig entries.
cost per mile#: Units used by some source datasets where costs are provided in currency per mile. When values_are_costs_per_mile is enabled during layer creation, reVRt scales those values by the cell size to obtain a per-cell cost.
cost surface#: Aggregate raster the routing engine traverses to minimize total cost between endpoints. It combines friction layers, adjusted barrier penalties, and any scenario-specific modifiers.
Dask#: Parallel computing library that powers reVRt’s chunked raster processing. Dask arrays allow large GeoTIFFs to be processed in memory-efficient blocks and executed across multiple cores.
dry mask#: Boolean mask representing onshore cells without landfall pixels. dry is one of the supported extent values used when scoping where a cost rule applies.
extent#: Named region identifier that limits where a layer build rule applies. Valid values are all, wet, wet+, landfall, dry+, and dry as defined in revrt.models.cost_layers. Each extent corresponds to one of the masks generated by Masks.
forced inclusion#: GeoTIFF layer that guarantees certain cells remain traversable. Any positive values in a forced inclusion raster cause the final combined cost to be set to zero for the same cells, ensuring a route can pass through critical locations.
friction layer#: Raster expressing the incremental cost required to traverse each cell. Friction layers capture factors such as terrain slope, land-use multipliers, and water crossings before barrier penalties are applied.
GeoTIFF#: Open geospatial raster format based on the TIFF specification that embeds projection metadata. reVRt relies on GeoTIFF files as the canonical interchange format for intermediate layers and masks.
landfall mask#: Boolean mask identifying shoreline cells at the interface between onshore and offshore extents. Landfall pixels can be included with either wet mask or dry mask variants depending on the requested extent.
LayeredFile#: HDF5-based container that stores aligned rasters, coordinates, and metadata used in routing workflows. LayeredFile instances back the data written to the routing file and expose helper methods for reading and writing layers consistently.
least-cost path#: Graph search procedure that computes the minimum-cost connection between a source and destination over the cost surface. reVRt uses least-cost-path solvers inside the Rust routing core.
masks#: Collection of boolean rasters generated by Masks to distinguish wet, dry, and landfall regions. Masks are referenced when applying extent filters, building barriers, and reporting statistics.
Pixi#: Cross-platform package and environment manager used to provision Python, Rust, and system dependencies for development, testing, and documentation tasks. Project commands such as pixi run ensure reproducible execution environments.
point of interconnection#: Electrical grid location where a project, plant, or study point connects to existing transmission infrastructure. Points of interconnection often serve as endpoints for routing scenarios.
PyO3#: Rust library that enables bi-directional interoperability with Python. reVRt’s high-performance routing algorithms are compiled as a PyO3 extension module and imported into Python as revrt._rust.
reV#: NLR’s reV tool that models generation profiles and supply curves for various generation types. reVRt complements reV by adding transmission routing capabilities that feed downstream analyses.
reVRt#: The reV Routing toolkit that prepares cost surfaces, runs routing simulations, and exports supporting analytics for transmission planning studies.
routing file#: HDF5 file produced by the cost preparation pipeline that stores coordinate grids, friction and barrier layers, metadata, and any derived statistics. The routing file is accessed through the LayeredFile API.
transmission corridor#: Buffered polygon around a candidate route used for downstream analytics such as land characterization and permitting review.
wet mask#: Boolean mask representing offshore cells without landfall pixels. wet and wet+ extents rely on the wet mask variants when filtering routing layers.
Zarr#: Chunked, cloud-friendly array storage format used by reVRt for some example inputs and regression fixtures. Zarr data enables lazy, parallel access patterns similar to Dask-backed rasters.