mapcomplete/Logic/FeatureSource/Sources/SnappingFeatureSource.ts

105 lines
3.9 KiB
TypeScript

import { FeatureSource } from "../FeatureSource"
import { Store, UIEventSource } from "../../UIEventSource"
import { Feature, Point } from "geojson"
import { GeoOperations } from "../../GeoOperations"
import { BBox } from "../../BBox"
export interface SnappingOptions {
/**
* If the distance is bigger then this amount, don't snap.
* In meter
*/
maxDistance: number
allowUnsnapped?: false | boolean
/**
* The snapped-to way will be written into this
*/
snappedTo?: UIEventSource<string>
/**
* The resulting snap coordinates will be written into this UIEventSource
*/
snapLocation?: UIEventSource<{ lon: number; lat: number }>
/**
* If the projected point is within `reusePointWithin`-meter of an already existing point
*/
reusePointWithin?: number
}
export default class SnappingFeatureSource implements FeatureSource {
public readonly features: Store<Feature<Point>[]>
/*Contains the id of the way it snapped to*/
public readonly snappedTo: Store<string>
private readonly _snappedTo: UIEventSource<string>
constructor(
snapTo: FeatureSource,
location: Store<{ lon: number; lat: number }>,
options: SnappingOptions
) {
const maxDistance = options?.maxDistance
this._snappedTo = options.snappedTo ?? new UIEventSource<string>(undefined)
this.snappedTo = this._snappedTo
const simplifiedFeatures = snapTo.features
.mapD((features) =>
features
.filter((feature) => feature.geometry.type !== "Point")
.map((f) => GeoOperations.forceLineString(<any>f))
)
.map(
(features) => {
const { lon, lat } = location.data
const loc: [number, number] = [lon, lat]
return features.filter((f) => BBox.get(f).isNearby(loc, maxDistance))
},
[location]
)
this.features = location.mapD(
({ lon, lat }) => {
const features = simplifiedFeatures.data
const loc: [number, number] = [lon, lat]
const maxDistance = (options?.maxDistance ?? 1000) / 1000
let bestSnap: Feature<Point, { "snapped-to": string; dist: number }> = undefined
for (const feature of features) {
if (feature.geometry.type !== "LineString") {
// TODO handle Polygons with holes
continue
}
const snapped = GeoOperations.nearestPoint(<any>feature, loc)
if (snapped.properties.dist > maxDistance) {
continue
}
if (
bestSnap === undefined ||
bestSnap.properties.dist > snapped.properties.dist
) {
snapped.properties["snapped-to"] = feature.properties.id
bestSnap = <any>snapped
}
}
this._snappedTo.setData(bestSnap?.properties?.["snapped-to"])
if (bestSnap === undefined && options?.allowUnsnapped) {
bestSnap = {
type: "Feature",
geometry: {
type: "Point",
coordinates: [lon, lat],
},
properties: {
"snapped-to": undefined,
dist: -1,
},
}
}
const c = bestSnap.geometry.coordinates
options?.snapLocation?.setData({ lon: c[0], lat: c[1] })
return [bestSnap]
},
[snapTo.features]
)
}
}