geojson-minimum-bounding-rectangle/dist/index.js

A library to compute the Minimum Bounding Rectangle of a GeoJSON polygon

import { convex } from '@turf/convex';
import { coordAll } from '@turf/meta';
import { centroid } from '@turf/centroid';
import { transformRotate } from '@turf/transform-rotate';
import { bearing } from '@turf/bearing';
import { envelope } from '@turf/envelope';
import { area } from '@turf/area';
import { distance } from '@turf/distance';
export function smallestSurroundingRectangleByArea(geoJsonInput) {
    const convexHull = convex(geoJsonInput);
    if (!convexHull)
        throw new Error("Can't calculate smallestSurroundingRectangleByArea for given geometry");
    const centroidCoords = centroid(convexHull);
    const allHullCoords = coordAll(convexHull);
    let minArea = Number.MAX_SAFE_INTEGER;
    let resultPolygon = null;
    for (let index = 0; index < allHullCoords.length - 1; index++) {
        let angle = bearing(allHullCoords[index], allHullCoords[index + 1]);
        let rotatedHull = transformRotate(convexHull, -1.0 * angle, {
            pivot: centroidCoords,
        });
        let envelopeOfHull = envelope(rotatedHull);
        let envelopeArea = area(envelopeOfHull);
        if (envelopeArea < minArea) {
            minArea = envelopeArea;
            resultPolygon = transformRotate(envelopeOfHull, angle, {
                pivot: centroidCoords,
            });
        }
    }
    return resultPolygon;
}
export function smallestSurroundingRectangleByWidth(geoJsonInput) {
    const convexHull = convex(geoJsonInput);
    if (!convexHull)
        throw new Error("Can't calculate smallestSurroundingRectangleByArea for given geometry");
    const centroidCoords = centroid(convexHull);
    const allHullCoords = coordAll(convexHull);
    let minWidth = Number.MAX_SAFE_INTEGER;
    let resultPolygon = null;
    for (let index = 0; index < allHullCoords.length - 1; index++) {
        let angle = bearing(allHullCoords[index], allHullCoords[index + 1]);
        let rotatedHull = transformRotate(convexHull, -1.0 * angle, {
            pivot: centroidCoords,
        });
        let envelopeOfHull = envelope(rotatedHull);
        let envelopeCoords = coordAll(envelopeOfHull);
        if (envelopeCoords.length > 4) {
            let side1 = distance(envelopeCoords[0], envelopeCoords[1]);
            let side2 = distance(envelopeCoords[1], envelopeCoords[2]);
            let width = Math.min(side1, side2);
            if (width < minWidth) {
                minWidth = width;
                resultPolygon = transformRotate(envelopeOfHull, angle, {
                    pivot: centroidCoords,
                });
            }
        }
    }
    return resultPolygon;
}
//# sourceMappingURL=index.js.map