Struct Transform 

pub struct Transform { /* private fields */ }

A reusable coordinate transformation between two CRS.

Create once with Transform::new, then call convert for each coordinate. All input/output coordinates use the CRS’s native units: degrees (lon/lat) for geographic CRS, meters for projected CRS.

Example

use proj_core::Transform;

let t = Transform::new("EPSG:4326", "EPSG:3857").unwrap();
let (x, y) = t.convert((-74.006, 40.7128)).unwrap();
assert!((x - (-8238310.0)).abs() < 1.0);

Implementations

impl Transform

pub fn new(from_crs: &str, to_crs: &str) -> Result<Self>

Create a transform from authority code strings (e.g., "EPSG:4326").

This is the primary constructor, matching the API pattern from C PROJ’s Proj::new_known_crs().

pub fn from_epsg(from: u32, to: u32) -> Result<Self>

Create a transform from EPSG codes directly.

pub fn from_crs_defs(from: &CrsDef, to: &CrsDef) -> Result<Self>

Create a transform from explicit CRS definitions.

Use this for custom CRS not in the built-in registry.

pub fn convert<T: Transformable>(&self, coord: T) -> Result<T>

Transform a single coordinate.

Input and output units are the native units of the respective CRS: degrees for geographic CRS, meters for projected CRS.

The return type matches the input type:

• (f64, f64) in → (f64, f64) out
• Coord in → Coord out
• geo_types::Coord<f64> in → geo_types::Coord<f64> out (with geo-types feature)

pub fn convert_batch<T: Transformable + Clone>( &self, coords: &[T], ) -> Result<Vec<T>>

Batch transform (sequential).

pub fn convert_batch_parallel<T: Transformable + Send + Sync + Clone>( &self, coords: &[T], ) -> Result<Vec<T>>

Batch transform with Rayon parallelism.