Struct Equirectangular 

pub struct Equirectangular;

Equirectangular projection: trivial linear mapping of lon/lat to meters.

Uses the WGS-84 semi-major axis (R = 6 378 137 m) as the scaling factor so that output units are meters at the equator. This is a zero-size type – construction is free.

Trait Implementations

impl Projection for Equirectangular

fn project(&self, geo: &GeoCoord) -> WorldCoord

Forward projection: geographic degrees to world meters.

x = R * lon_rad, y = R * lat_rad, z = alt (passthrough).

fn unproject(&self, world: &WorldCoord) -> GeoCoord

Inverse projection: world meters back to geographic degrees.

lat = degrees(y / R), lon = degrees(x / R), alt = z.

fn scale_factor(&self, geo: &GeoCoord) -> f64

Scale factor for Equirectangular: sec(lat) = 1 / cos(lat).

The projection maps longitude linearly, so X distances are stretched relative to true distances by sec(lat), the same as the meridian convergence factor. Along Y the scale is 1.0, so this returns the maximum linear distortion at the point.

fn projection_bounds(&self) -> GeoBounds

The geographic bounding box of valid input for this projection.