City-Lifeline-Cockpit/tools/city-massing/primary-area.mjs

import * as turf from '@turf/turf'

export const PRIMARY_AREA_BOUNDS = Object.freeze([
    110.328749941417,
    28.3917230659234,
    110.465779226663,
    28.4913038992907,
])

const primaryArea = turf.bboxPolygon(PRIMARY_AREA_BOUNDS)

export function isWithinPrimaryArea(feature, bounds = PRIMARY_AREA_BOUNDS) {
    return turf.booleanWithin(feature, turf.bboxPolygon(bounds))
}

export function clipFeatureToBounds(feature, bounds = PRIMARY_AREA_BOUNDS) {
    const type = feature.geometry?.type
    let clipped
    if (type === 'LineString' || type === 'MultiLineString') {
        clipped = turf.bboxClip(feature, bounds)
    } else if (type === 'Polygon' || type === 'MultiPolygon') {
        clipped = turf.intersect(turf.featureCollection([feature, turf.bboxPolygon(bounds)]))
    } else {
        clipped = turf.booleanWithin(feature, primaryArea) ? feature : null
    }
    if (!clipped) return null
    const coordinates = clipped.geometry?.coordinates
    if (Array.isArray(coordinates) && coordinates.length === 0) return null
    if (Array.isArray(coordinates) && coordinates.every((part) => Array.isArray(part) && part.length === 0)) return null
    if (turf.area(clipped) === 0 && type !== 'LineString' && type !== 'MultiLineString') return null
    return { ...clipped, properties: { ...feature.properties } }
}

export function isInsidePrimaryArea(point) {
    return point.length === 2 &&
        Number.isFinite(point[0]) &&
        Number.isFinite(point[1]) &&
        point[0] >= PRIMARY_AREA_BOUNDS[0] &&
        point[0] <= PRIMARY_AREA_BOUNDS[2] &&
        point[1] >= PRIMARY_AREA_BOUNDS[1] &&
        point[1] <= PRIMARY_AREA_BOUNDS[3]
}