/**
 * Inner projection that accepts a pre-computed `worldSize` (= tileSize * 2^zoom).
 *
 * Exposed so hot loops that project dozens of points per frame (e.g. edge-label
 * layout) can hoist `Math.pow(2, zoom)` out of the per-vertex work. Most callers
 * should prefer the zoom-based {@link lngLatToWebMercatorPx} wrapper.
 */
export declare const lngLatToMercatorPxWS: (lng: number, lat: number, worldSize: number) => readonly [number, number];
/**
 * Inverse of {@link lngLatToMercatorPxWS}: map a pixel coordinate back to
 * [lng, lat] given a pre-computed `worldSize`.
 */
export declare const mercatorPxToLngLatWS: (px: number, py: number, worldSize: number) => readonly [number, number];
/**
 * Project a [lng, lat] coordinate to absolute Web Mercator pixel space at the
 * given zoom. This is the same projection formula map adapters use internally,
 * so pixel-space measurements derived here agree with the rendered map.
 */
export declare const lngLatToWebMercatorPx: (lng: number, lat: number, zoom: number, tileSize?: number) => readonly [number, number];
/**
 * Inverse of {@link lngLatToWebMercatorPx}: map an absolute Web Mercator pixel
 * coordinate back to [lng, lat] at the given zoom.
 */
export declare const webMercatorPxToLngLat: (px: number, py: number, zoom: number, tileSize?: number) => readonly [number, number];
/**
 * Convert a pixel distance to latitude degrees at a given zoom level,
 * accounting for Web Mercator latitude distortion (latitude pixels scale by
 * sec(lat)).
 */
export declare const pixelsToLatDegrees: (pixels: number, zoom: number, latDeg: number, tileSize?: number) => number;
/**
 * Compute the pixel length of a line segment at a given zoom level,
 * accounting for Web Mercator latitude distortion.
 *
 * Web Mercator tile math: worldSize = tileSize * 2^zoom pixels for 360 degrees of longitude.
 * Latitude pixels scale by sec(lat).
 *
 * Relocated from `@trackunit/react-map` (per ADR-0018 follow-up) since this is pure
 * Mercator math with no React or DS semantics — appropriate for a vanilla geo utility lib.
 *
 * @param x0 - Start longitude (degrees)
 * @param y0 - Start latitude (degrees)
 * @param x1 - End longitude (degrees)
 * @param y1 - End latitude (degrees)
 * @param zoom - Map zoom level
 * @param midLatDeg - Mid-point latitude for distortion correction (degrees)
 * @param tileSize - Tile size in pixels (default 256)
 */
export declare const edgePixelLength: (x0: number, y0: number, x1: number, y1: number, zoom: number, midLatDeg: number, tileSize?: number) => number;