Refactor route merging logic for improved performance

modules/io/export.js

@@ -465,9 +465,20 @@ function saveGeoJSON_Cells() {
 }
 
 function saveGeoJSON_Routes() {
-  const features = pack.routes.map(({id, points, cells, group}) => {
-    const coordinates = points || getRoutePoints(cells, group);
-    return {type: "Feature", geometry: {type: "LineString", coordinates}, properties: {id, group}};
+  const {cells, burgs} = pack;
+  let points = cells.p.map(([x, y], cellId) => {
+    const burgId = cells.burg[cellId];
+    if (burgId) return [burgs[burgId].x, burgs[burgId].y];
+    return [x, y];
+  });
+
+  const features = pack.routes.map(route => {
+    const coordinates = route.points || getRoutePoints(route, points);
+    return {
+      type: "Feature",
+      geometry: {type: "LineString", coordinates},
+      properties: {id: route.id, group: route.group}
+    };
   });
   const json = {type: "FeatureCollection", features};
 

modules/routes-generator.js

@@ -124,35 +124,47 @@ window.Routes = (function () {
     function combineRoutes() {
       const routes = [];
 
-      for (const {feature, cells} of mainRoads) {
+      for (const {feature, cells, merged} of mergeRoutes(mainRoads)) {
+        if (merged) continue;
         routes.push({i: routes.length, group: "roads", feature, cells});
       }
 
-      // merge routes so that the last cells of one route are the first cells of the next route
-      for (let i = 0; i < trails.length; i++) {
-        const {cells, feature, merged} = trails[i];
+      for (const {feature, cells, merged} of mergeRoutes(trails)) {
         if (merged) continue;
-
-        for (let j = i + 1; j < trails.length; j++) {
-          const nextTrail = trails[j];
-          if (nextTrail.merged) continue;
-
-          if (nextTrail.cells[0] === cells.at(-1)) {
-            cells.push(...nextTrail.cells.slice(1));
-            nextTrail.merged = true;
-          }
-        }
-
         routes.push({i: routes.length, group: "trails", feature, cells});
       }
 
-      for (const {feature, cells} of seaRoutes) {
+      for (const {feature, cells, merged} of mergeRoutes(seaRoutes)) {
+        if (merged) continue;
         routes.push({i: routes.length, group: "searoutes", feature, cells});
       }
 
       return routes;
     }
 
+    // merge routes so that the last cell of one route is the first cell of the next route
+    function mergeRoutes(routes) {
+      let routesMerged = 0;
+
+      for (let i = 0; i < routes.length; i++) {
+        const thisRoute = routes[i];
+        if (thisRoute.merged) continue;
+
+        for (let j = i + 1; j < routes.length; j++) {
+          const nextRoute = routes[j];
+          if (nextRoute.merged) continue;
+
+          if (nextRoute.cells.at(0) === thisRoute.cells.at(-1)) {
+            routesMerged++;
+            thisRoute.cells = thisRoute.cells.concat(nextRoute.cells.slice(1));
+            nextRoute.merged = true;
+          }
+        }
+      }
+
+      return routesMerged > 1 ? mergeRoutes(routes) : routes;
+    }
+
     function buildLinks(routes) {
       const links = {};
 

modules/ui/layers.js

@@ -1645,10 +1645,17 @@ function drawRoutes() {
   const routePaths = {};
   const lineGen = d3.line();
 
+  const {cells, burgs} = pack;
+  let points = cells.p.map(([x, y], cellId) => {
+    const burgId = cells.burg[cellId];
+    if (burgId) return [burgs[burgId].x, burgs[burgId].y];
+    return [x, y];
+  });
+
   for (const route of pack.routes) {
     const {i, group} = route;
     lineGen.curve(ROUTE_CURVES[group] || ROUTE_CURVES.default);
-    const routePoints = getRoutePoints(route);
+    const routePoints = getRoutePoints(route, points);
     const path = round(lineGen(routePoints), 1);
 
     if (!routePaths[group]) routePaths[group] = [];
@@ -1666,49 +1673,42 @@ function drawRoutes() {
 const ROUTES_SHARP_ANGLE = 135;
 const ROUTES_VERY_SHARP_ANGLE = 115;
 
-function getRoutePoints({points, cells: cellIds, group}) {
-  if (points) return points;
-  const {cells, burgs} = pack;
+function getRoutePoints(route, points) {
+  if (route.points) return route.points;
+  const routePoints = route.cells.map(cellId => points[cellId]);
 
-  const routePoints = cellIds.map(cellId => {
-    const burgId = cells.burg[cellId];
-    if (burgId) {
-      const {x, y} = burgs[burgId];
-      return [x, y];
+  if (route.group !== "searoutes2") {
+    for (let i = 1; i < route.cells.length - 1; i++) {
+      const cellId = route.cells[i];
+      if (pack.cells.burg[cellId]) continue;
+
+      const [prevX, prevY] = routePoints[i - 1];
+      const [currX, currY] = routePoints[i];
+      const [nextX, nextY] = routePoints[i + 1];
+
+      const dAx = prevX - currX;
+      const dAy = prevY - currY;
+      const dBx = nextX - currX;
+      const dBy = nextY - currY;
+      const angle = Math.abs((Math.atan2(dAx * dBy - dAy * dBx, dAx * dBx + dAy * dBy) * 180) / Math.PI);
+
+      if (angle < ROUTES_SHARP_ANGLE) {
+        const middleX = (prevX + nextX) / 2;
+        const middleY = (prevY + nextY) / 2;
+        let newX, newY;
+
+        if (angle < ROUTES_VERY_SHARP_ANGLE) {
+          newX = rn((currX + middleX * 2) / 3, 2);
+          newY = rn((currY + middleY * 2) / 3, 2);
+        } else {
+          newX = rn((currX + middleX) / 2, 2);
+          newY = rn((currY + middleY) / 2, 2);
         }
 
-    return cells.p[cellId];
-  });
-
-  if (group !== "searoutes") {
-    for (let i = 1; i < cellIds.length - 1; i++) {
-      const cellId = cellIds[i];
-      if (cells.burg[cellId]) continue;
-
-      const prev = routePoints[i - 1];
-      const that = routePoints[i];
-      const next = routePoints[i + 1];
-
-      const dAx = prev[0] - that[0];
-      const dAy = prev[1] - that[1];
-      const dBx = next[0] - that[0];
-      const dBy = next[1] - that[1];
-      const angle = (Math.atan2(dAx * dBy - dAy * dBx, dAx * dBx + dAy * dBy) * 180) / Math.PI;
-
-      if (Math.abs(angle) < ROUTES_SHARP_ANGLE) {
-        const middleX = (prev[0] + next[0]) / 2;
-        const middleY = (prev[1] + next[1]) / 2;
-
-        if (Math.abs(angle) < ROUTES_VERY_SHARP_ANGLE) {
-          const newX = (that[0] + middleX * 2) / 3;
-          const newY = (that[1] + middleY * 2) / 3;
+        if (findCell(newX, newY) === cellId) {
           routePoints[i] = [newX, newY];
-          continue;
+          points[cellId] = routePoints[i]; // change cell coordinate for all routes
         }
-
-        const newX = (that[0] + middleX) / 2;
-        const newY = (that[1] + middleY) / 2;
-        routePoints[i] = [newX, newY];
       }
     }
   }

modules/ui/routes-editor.js

@@ -20,7 +20,7 @@ function editRoute(id) {
 
   updateRouteData();
 
-  drawControlPoints(getRoutePoints(getRoute()));
+  drawControlPoints(getPoints());
   drawCells();
 
   $("#routeEditor").dialog({
@@ -49,6 +49,17 @@ function editRoute(id) {
     return route;
   }
 
+  function getPoints() {
+    const {cells, burgs} = pack;
+    let points = cells.p.map(([x, y], cellId) => {
+      const burgId = cells.burg[cellId];
+      if (burgId) return [burgs[burgId].x, burgs[burgId].y];
+      return [x, y];
+    });
+
+    return getRoutePoints(getRoute(), points);
+  }
+
   function updateRouteData() {
     const route = getRoute();