Expand description
Pure-Rust coordinate transformation library.
No C dependencies, no unsafe, WASM-compatible.
The primary type is Transform, which provides CRS-to-CRS coordinate
transformation using authority codes (e.g., "EPSG:4326").
For area-aware or policy-constrained selection, use
Transform::with_selection_options and inspect
Transform::selected_operation /
Transform::selection_diagnostics.
The registry, operation, and grid modules expose the embedded
operation catalog, selection metadata, and NTv2 grid-provider interfaces.
§Example
use proj_core::Transform;
// Create a transform from WGS84 geographic to Web Mercator
let t = Transform::new("EPSG:4326", "EPSG:3857").unwrap();
// Transform NYC coordinates (lon, lat in degrees) → (x, y in meters)
let (x, y) = t.convert((-74.006, 40.7128)).unwrap();
assert!((x - (-8238310.0)).abs() < 100.0);
// Inverse: Web Mercator → WGS84
let inv = Transform::new("EPSG:3857", "EPSG:4326").unwrap();
let (lon, lat) = inv.convert((x, y)).unwrap();
assert!((lon - (-74.006)).abs() < 1e-6);Re-exports§
pub use coord::Bounds;pub use coord::Coord;pub use coord::Coord3D;pub use coord::Transformable;pub use coord::Transformable3D;pub use crs::CrsDef;pub use crs::GeographicCrsDef;pub use crs::LinearUnit;pub use crs::ProjectedCrsDef;pub use crs::ProjectionMethod;pub use datum::Datum;pub use datum::DatumGridShift;pub use datum::DatumGridShiftEntry;pub use datum::DatumToWgs84;pub use datum::HelmertParams;pub use ellipsoid::Ellipsoid;pub use error::Error;pub use error::Result;pub use grid::EmbeddedGridProvider;pub use grid::FilesystemGridProvider;pub use grid::GridDefinition;pub use grid::GridError;pub use grid::GridFormat;pub use grid::GridHandle;pub use grid::GridProvider;pub use grid::GridSample;pub use operation::AreaOfInterest;pub use operation::AreaOfInterestCrs;pub use operation::AreaOfUse;pub use operation::CoordinateOperation;pub use operation::CoordinateOperationId;pub use operation::CoordinateOperationMetadata;pub use operation::GridCoverageMiss;pub use operation::GridId;pub use operation::GridInterpolation;pub use operation::GridShiftDirection;pub use operation::OperationAccuracy;pub use operation::OperationMatchKind;pub use operation::OperationMethod;pub use operation::OperationSelectionDiagnostics;pub use operation::OperationStep;pub use operation::OperationStepDirection;pub use operation::SelectionOptions;pub use operation::SelectionPolicy;pub use operation::SelectionReason;pub use operation::SkippedOperation;pub use operation::SkippedOperationReason;pub use operation::TransformOutcome;pub use registry::lookup_datum_epsg;pub use registry::lookup_epsg;pub use registry::lookup_operation;pub use registry::operation_candidates_between;pub use registry::operation_candidates_between_with_selection_options;pub use registry::operations_between;pub use transform::Transform;