forked from MapComplete/MapComplete
		
	
		
			
				
	
	
		
			300 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			300 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| import { OsmObject, OsmWay } from "../OsmObject"
 | |
| import { Changes } from "../Changes"
 | |
| import { GeoOperations } from "../../GeoOperations"
 | |
| import OsmChangeAction from "./OsmChangeAction"
 | |
| import { ChangeDescription } from "./ChangeDescription"
 | |
| import RelationSplitHandler from "./RelationSplitHandler"
 | |
| 
 | |
| interface SplitInfo {
 | |
|     originalIndex?: number // or negative for new elements
 | |
|     lngLat: [number, number]
 | |
|     doSplit: boolean
 | |
| }
 | |
| 
 | |
| export default class SplitAction extends OsmChangeAction {
 | |
|     private readonly wayId: string
 | |
|     private readonly _splitPointsCoordinates: [number, number][] // lon, lat
 | |
|     private _meta: { theme: string; changeType: "split" }
 | |
|     private _toleranceInMeters: number
 | |
|     private _withNewCoordinates: (coordinates: [number, number][]) => void
 | |
| 
 | |
|     /**
 | |
|      * Create a changedescription for splitting a point.
 | |
|      * Will attempt to reuse existing points
 | |
|      * @param wayId
 | |
|      * @param splitPointCoordinates: lon, lat
 | |
|      * @param meta
 | |
|      * @param toleranceInMeters: if a splitpoint closer then this amount of meters to an existing point, the existing point will be used to split the line instead of a new point
 | |
|      * @param withNewCoordinates: an optional callback which will leak the new coordinates of the original way
 | |
|      */
 | |
|     constructor(
 | |
|         wayId: string,
 | |
|         splitPointCoordinates: [number, number][],
 | |
|         meta: { theme: string },
 | |
|         toleranceInMeters = 5,
 | |
|         withNewCoordinates?: (coordinates: [number, number][]) => void
 | |
|     ) {
 | |
|         super(wayId, true)
 | |
|         this.wayId = wayId
 | |
|         this._splitPointsCoordinates = splitPointCoordinates
 | |
|         this._toleranceInMeters = toleranceInMeters
 | |
|         this._withNewCoordinates = withNewCoordinates
 | |
|         this._meta = { ...meta, changeType: "split" }
 | |
|     }
 | |
| 
 | |
|     private static SegmentSplitInfo(splitInfo: SplitInfo[]): SplitInfo[][] {
 | |
|         const wayParts = []
 | |
|         let currentPart = []
 | |
|         for (const splitInfoElement of splitInfo) {
 | |
|             currentPart.push(splitInfoElement)
 | |
| 
 | |
|             if (splitInfoElement.doSplit) {
 | |
|                 // We have to do a split!
 | |
|                 // We add the current index to the currentParts, flush it and add it again
 | |
|                 wayParts.push(currentPart)
 | |
|                 currentPart = [splitInfoElement]
 | |
|             }
 | |
|         }
 | |
|         wayParts.push(currentPart)
 | |
|         return wayParts.filter((wp) => wp.length > 0)
 | |
|     }
 | |
| 
 | |
|     async CreateChangeDescriptions(changes: Changes): Promise<ChangeDescription[]> {
 | |
|         const originalElement = <OsmWay>await OsmObject.DownloadObjectAsync(this.wayId)
 | |
|         const originalNodes = originalElement.nodes
 | |
| 
 | |
|         // First, calculate the splitpoints and remove points close to one another
 | |
|         const splitInfo = this.CalculateSplitCoordinates(originalElement, this._toleranceInMeters)
 | |
|         // Now we have a list with e.g.
 | |
|         // [ { originalIndex: 0}, {originalIndex: 1, doSplit: true}, {originalIndex: 2}, {originalIndex: undefined, doSplit: true}, {originalIndex: 3}]
 | |
| 
 | |
|         // Lets change 'originalIndex' to the actual node id first (or assign a new id if needed):
 | |
|         for (const element of splitInfo) {
 | |
|             if (element.originalIndex >= 0) {
 | |
|                 element.originalIndex = originalElement.nodes[element.originalIndex]
 | |
|             } else {
 | |
|                 element.originalIndex = changes.getNewID()
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         // Next up is creating actual parts from this
 | |
|         const wayParts: SplitInfo[][] = SplitAction.SegmentSplitInfo(splitInfo)
 | |
|         // Allright! At this point, we have our new ways!
 | |
|         // Which one is the longest of them (and can keep the id)?
 | |
| 
 | |
|         let longest = undefined
 | |
|         for (const wayPart of wayParts) {
 | |
|             if (longest === undefined) {
 | |
|                 longest = wayPart
 | |
|                 continue
 | |
|             }
 | |
|             if (wayPart.length > longest.length) {
 | |
|                 longest = wayPart
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         const changeDescription: ChangeDescription[] = []
 | |
|         // Let's create the new nodes as needed
 | |
|         for (const element of splitInfo) {
 | |
|             if (element.originalIndex >= 0) {
 | |
|                 continue
 | |
|             }
 | |
|             changeDescription.push({
 | |
|                 type: "node",
 | |
|                 id: element.originalIndex,
 | |
|                 changes: {
 | |
|                     lon: element.lngLat[0],
 | |
|                     lat: element.lngLat[1],
 | |
|                 },
 | |
|                 meta: this._meta,
 | |
|             })
 | |
|         }
 | |
| 
 | |
|         // The ids of all the ways (including the original)
 | |
|         const allWayIdsInOrder: number[] = []
 | |
| 
 | |
|         const allWaysNodesInOrder: number[][] = []
 | |
|         // Lets create OsmWays based on them
 | |
|         for (const wayPart of wayParts) {
 | |
|             let isOriginal = wayPart === longest
 | |
|             if (isOriginal) {
 | |
|                 // We change the existing way
 | |
|                 const nodeIds = wayPart.map((p) => p.originalIndex)
 | |
|                 const newCoordinates = wayPart.map((p) => p.lngLat)
 | |
|                 changeDescription.push({
 | |
|                     type: "way",
 | |
|                     id: originalElement.id,
 | |
|                     changes: {
 | |
|                         coordinates: newCoordinates,
 | |
|                         nodes: nodeIds,
 | |
|                     },
 | |
|                     meta: this._meta,
 | |
|                 })
 | |
|                 if (this._withNewCoordinates) {
 | |
|                     this._withNewCoordinates(newCoordinates)
 | |
|                 }
 | |
|                 allWayIdsInOrder.push(originalElement.id)
 | |
|                 allWaysNodesInOrder.push(nodeIds)
 | |
|             } else {
 | |
|                 let id = changes.getNewID()
 | |
|                 // Copy the tags from the original object onto the new
 | |
|                 const kv = []
 | |
|                 for (const k in originalElement.tags) {
 | |
|                     if (!originalElement.tags.hasOwnProperty(k)) {
 | |
|                         continue
 | |
|                     }
 | |
|                     if (k.startsWith("_") || k === "id") {
 | |
|                         continue
 | |
|                     }
 | |
|                     kv.push({ k: k, v: originalElement.tags[k] })
 | |
|                 }
 | |
|                 const nodeIds = wayPart.map((p) => p.originalIndex)
 | |
|                 if (nodeIds.length <= 1) {
 | |
|                     console.error("Got a segment with only one node - skipping")
 | |
|                     continue
 | |
|                 }
 | |
|                 changeDescription.push({
 | |
|                     type: "way",
 | |
|                     id: id,
 | |
|                     tags: kv,
 | |
|                     changes: {
 | |
|                         coordinates: wayPart.map((p) => p.lngLat),
 | |
|                         nodes: nodeIds,
 | |
|                     },
 | |
|                     meta: this._meta,
 | |
|                 })
 | |
| 
 | |
|                 allWayIdsInOrder.push(id)
 | |
|                 allWaysNodesInOrder.push(nodeIds)
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         // At last, we still have to check that we aren't part of a relation...
 | |
|         // At least, the order of the ways is identical, so we can keep the same roles
 | |
|         const relations = await OsmObject.DownloadReferencingRelations(this.wayId)
 | |
|         for (const relation of relations) {
 | |
|             const changDescrs = await new RelationSplitHandler(
 | |
|                 {
 | |
|                     relation: relation,
 | |
|                     allWayIdsInOrder: allWayIdsInOrder,
 | |
|                     originalNodes: originalNodes,
 | |
|                     allWaysNodesInOrder: allWaysNodesInOrder,
 | |
|                     originalWayId: originalElement.id,
 | |
|                 },
 | |
|                 this._meta.theme
 | |
|             ).CreateChangeDescriptions(changes)
 | |
|             changeDescription.push(...changDescrs)
 | |
|         }
 | |
| 
 | |
|         // And we have our objects!
 | |
|         // Time to upload
 | |
| 
 | |
|         return changeDescription
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * Calculates the actual points to split
 | |
|      * If another point is closer then ~5m, we reuse that point
 | |
|      */
 | |
|     private CalculateSplitCoordinates(osmWay: OsmWay, toleranceInM = 5): SplitInfo[] {
 | |
|         const wayGeoJson = osmWay.asGeoJson()
 | |
|         // Should be [lon, lat][]
 | |
|         const originalPoints: [number, number][] = osmWay.coordinates.map((c) => [c[1], c[0]])
 | |
|         const allPoints: {
 | |
|             // lon, lat
 | |
|             coordinates: [number, number]
 | |
|             isSplitPoint: boolean
 | |
|             originalIndex?: number // Original index
 | |
|             dist: number // Distance from the nearest point on the original line
 | |
|             location: number // Distance from the start of the way
 | |
|         }[] = this._splitPointsCoordinates.map((c) => {
 | |
|             // From the turf.js docs:
 | |
|             // The properties object will contain three values:
 | |
|             // - `index`: closest point was found on nth line part,
 | |
|             // - `dist`: distance between pt and the closest point,
 | |
|             // `location`: distance along the line between start and the closest point.
 | |
|             let projected = GeoOperations.nearestPoint(wayGeoJson, c)
 | |
|             // c is lon lat
 | |
|             return {
 | |
|                 coordinates: c,
 | |
|                 isSplitPoint: true,
 | |
|                 dist: projected.properties.dist,
 | |
|                 location: projected.properties.location,
 | |
|             }
 | |
|         })
 | |
| 
 | |
|         // We have a bunch of coordinates here: [ [lon, lon], [lat, lon], ...] ...
 | |
|         // We project them onto the line (which should yield pretty much the same point and add them to allPoints
 | |
|         for (let i = 0; i < originalPoints.length; i++) {
 | |
|             let originalPoint = originalPoints[i]
 | |
|             let projected = GeoOperations.nearestPoint(wayGeoJson, originalPoint)
 | |
|             allPoints.push({
 | |
|                 coordinates: originalPoint,
 | |
|                 isSplitPoint: false,
 | |
|                 location: projected.properties.location,
 | |
|                 originalIndex: i,
 | |
|                 dist: projected.properties.dist,
 | |
|             })
 | |
|         }
 | |
|         // At this point, we have a list of both the split point and the old points, with some properties to discriminate between them
 | |
|         // We sort this list so that the new points are at the same location
 | |
|         allPoints.sort((a, b) => a.location - b.location)
 | |
| 
 | |
|         for (let i = allPoints.length - 2; i >= 1; i--) {
 | |
|             // We 'merge' points with already existing nodes if they are close enough to avoid closeby elements
 | |
| 
 | |
|             // Note the loop bounds: we skip the first two and last two elements:
 | |
|             // The first and last element are always part of the original way and should be kept
 | |
|             // Furthermore, we run in reverse order as we'll delete elements on the go
 | |
| 
 | |
|             const point = allPoints[i]
 | |
|             if (point.originalIndex !== undefined) {
 | |
|                 // We keep the original points
 | |
|                 continue
 | |
|             }
 | |
| 
 | |
|             // At this point, 'dist' told us the point is pretty close to an already existing point.
 | |
|             // Lets see which (already existing) point is closer and mark it as splitpoint
 | |
|             const nextPoint = allPoints[i + 1]
 | |
|             const prevPoint = allPoints[i - 1]
 | |
|             const distToNext = nextPoint.location - point.location
 | |
|             const distToPrev = point.location - prevPoint.location
 | |
| 
 | |
|             if (distToNext * 1000 > toleranceInM && distToPrev * 1000 > toleranceInM) {
 | |
|                 // Both are too far away to mark them as the split point
 | |
|                 continue
 | |
|             }
 | |
| 
 | |
|             let closest = nextPoint
 | |
|             if (distToNext > distToPrev) {
 | |
|                 closest = prevPoint
 | |
|             }
 | |
|             // Ok, we have a closest point!
 | |
|             if (closest.originalIndex === 0 || closest.originalIndex === originalPoints.length) {
 | |
|                 // We can not split on the first or last points...
 | |
|                 continue
 | |
|             }
 | |
|             closest.isSplitPoint = true
 | |
|             allPoints.splice(i, 1)
 | |
|         }
 | |
| 
 | |
|         const splitInfo: SplitInfo[] = []
 | |
|         let nextId = -1 // Note: these IDs are overwritten later on, no need to use a global counter here
 | |
| 
 | |
|         for (const p of allPoints) {
 | |
|             let index = p.originalIndex
 | |
|             if (index === undefined) {
 | |
|                 index = nextId
 | |
|                 nextId--
 | |
|             }
 | |
|             const splitInfoElement = {
 | |
|                 originalIndex: index,
 | |
|                 lngLat: p.coordinates,
 | |
|                 doSplit: p.isSplitPoint,
 | |
|             }
 | |
|             splitInfo.push(splitInfoElement)
 | |
|         }
 | |
| 
 | |
|         return splitInfo
 | |
|     }
 | |
| }
 |