Revert "Speed up path simplification with path details/instructions (#…

…1782)"

This reverts commit 2ebac80

api/src/main/java/com/graphhopper/util/PointList.java

@@ -565,7 +565,7 @@ public void parse2DJSON(String str) {
             if (latlon.trim().length() == 0)
                 continue;
 
-            String[] ll = latlon.split(",");
+            String ll[] = latlon.split(",");
             String lat = ll[1].replace("]", "").trim();
             add(Double.parseDouble(lat), Double.parseDouble(ll[0].trim()), Double.NaN);
         }

api/src/main/java/com/graphhopper/util/ShallowImmutablePointList.java

@@ -57,10 +57,6 @@ public boolean isEmpty() {
         return size() == 0;
     }
 
-    public String getIntervalString() {
-        return "[" + fromOffset + ", " + toOffset + "]";
-    }
-
     @Override
     public double getLatitude(int index) {
         if (index > getSize())

core/src/main/java/com/graphhopper/util/DouglasPeucker.java

@@ -64,22 +64,16 @@ public int simplify(PointList points) {
         return simplify(points, 0, points.size() - 1);
     }
 
-    public int simplify(PointList points, int fromIndex, int lastIndex) {
-        return simplify(points, fromIndex, lastIndex, true);
-    }
-
     /**
      * Simplifies a part of the <code>points</code>. The <code>fromIndex</code> and <code>lastIndex</code>
      * are guaranteed to be kept.
      *
      * @param points    The PointList to simplify
-     * @param fromIndex Start index to simplify, should be <= <code>lastIndex</code>
+     * @param fromIndex Start index to simplify, should be >= <code>lastIndex</code>
      * @param lastIndex Simplify up to this index
-     * @param compress  Whether or not the <code>points</code> shall be compressed or not, if set to false no points
-     *                  are actually removed, but instead their lat/lon/ele is only set to NaN
      * @return The number of removed points
      */
-    public int simplify(PointList points, int fromIndex, int lastIndex, boolean compress) {
+    public int simplify(PointList points, int fromIndex, int lastIndex) {
         int removed = 0;
         int size = lastIndex - fromIndex;
         if (approx) {
@@ -95,12 +89,43 @@ public int simplify(PointList points, int fromIndex, int lastIndex, boolean comp
             removed = subSimplify(points, fromIndex, lastIndex);
         }
 
-        if (removed > 0 && compress)
-            removeNaN(points);
+        if (removed > 0)
+            compressNew(points, removed);
 
         return removed;
     }
 
+    /**
+     * compress list: move points into EMPTY slots
+     */
+    void compressNew(PointList points, int removed) {
+        int freeIndex = -1;
+        for (int currentIndex = 0; currentIndex < points.getSize(); currentIndex++) {
+            if (Double.isNaN(points.getLatitude(currentIndex))) {
+                if (freeIndex < 0)
+                    freeIndex = currentIndex;
+
+                continue;
+            } else if (freeIndex < 0) {
+                continue;
+            }
+
+            points.set(freeIndex, points.getLatitude(currentIndex), points.getLongitude(currentIndex), points.getElevation(currentIndex));
+            points.set(currentIndex, Double.NaN, Double.NaN, Double.NaN);
+            // find next free index
+            int max = currentIndex;
+            int searchIndex = freeIndex + 1;
+            freeIndex = currentIndex;
+            for (; searchIndex < max; searchIndex++) {
+                if (Double.isNaN(points.getLatitude(searchIndex))) {
+                    freeIndex = searchIndex;
+                    break;
+                }
+            }
+        }
+        points.trimToSize(points.getSize() - removed);
+    }
+
     // keep the points of fromIndex and lastIndex
     int subSimplify(PointList points, int fromIndex, int lastIndex) {
         if (lastIndex - fromIndex < 2) {
@@ -142,18 +167,4 @@ int subSimplify(PointList points, int fromIndex, int lastIndex) {
         return counter;
     }
 
-    /**
-     * Fills all entries of the point list that are NaN with the subsequent values (and therefore shortens the list)
-     */
-    static void removeNaN(PointList pointList) {
-        int curr = 0;
-        for (int i = 0; i < pointList.size(); i++) {
-            if (!Double.isNaN(pointList.getLatitude(i))) {
-                pointList.set(curr, pointList.getLatitude(i), pointList.getLongitude(i), pointList.getElevation(i));
-                curr++;
-            }
-        }
-        pointList.trimToSize(curr);
-    }
-
 }

core/src/main/java/com/graphhopper/util/PathMerger.java

@@ -56,7 +56,7 @@ public class PathMerger {
     private DouglasPeucker douglasPeucker = DP;
     private boolean calcPoints = true;
     private PathDetailsBuilderFactory pathBuilderFactory;
-    private List<String> requestedPathDetails = Collections.emptyList();
+    private List<String> requestedPathDetails = Collections.EMPTY_LIST;
     private double favoredHeading = Double.NaN;
 
     public PathMerger(Graph graph, Weighting weighting) {
@@ -117,7 +117,7 @@ public void doWork(PathWrapper altRsp, List<Path> paths, EncodingManager encodin
                 if (!il.isEmpty()) {
                     fullInstructions.addAll(il);
 
-                    // for all paths except the last replace the FinishInstruction with a ViaInstruction
+                    // for all paths except the last replace the FinishInstruction with a ViaInstructionn
                     if (pathIndex + 1 < paths.size()) {
                         ViaInstruction newInstr = new ViaInstruction(fullInstructions.get(fullInstructions.size() - 1));
                         newInstr.setViaCount(pathIndex + 1);
@@ -167,7 +167,8 @@ public void doWork(PathWrapper altRsp, List<Path> paths, EncodingManager encodin
                 setTime(fullTimeInMillis);
 
         if (allFound && simplifyResponse && (calcPoints || enableInstructions)) {
-            PathSimplification.simplify(altRsp, douglasPeucker, enableInstructions);
+            PathSimplification ps = new PathSimplification(altRsp, douglasPeucker, enableInstructions);
+            ps.simplify();
         }
     }