Fix inappropriate approximation of Math.exp

brouter-core/src/main/java/btools/router/KinematicPath.java

@@ -5,9 +5,6 @@
  */
 package btools.router;
 
-import btools.util.FastMath;
-
-
 final class KinematicPath extends OsmPath {
   private double ekin; // kinetic energy (Joule)
   private double totalTime;  // travel time (seconds)
@@ -57,7 +54,7 @@ protected double processWaySection(RoutingContext rc, double dist, double delta_
 
         double curveSpeed = aa > 10. ? 200. / aa : 20.;
         double distanceTime = dist / curveSpeed;
-        double decayFactor = FastMath.exp(-distanceTime / km.turnAngleDecayTime);
+        double decayFactor = Math.exp(-distanceTime / km.turnAngleDecayTime);
         floatingAngleLeft = (float) (floatingAngleLeft * decayFactor);
         floatingAngleRight = (float) (floatingAngleRight * decayFactor);
 

brouter-core/src/main/java/btools/router/StdPath.java

@@ -5,8 +5,6 @@
  */
 package btools.router;
 
-import btools.util.FastMath;
-
 final class StdPath extends OsmPath {
   /**
    * The elevation-hysteresis-buffer (0-10 m)
@@ -200,7 +198,7 @@ private double calcIncline(double dist) {
     } else if (elevation_buffer < -min_delta) {
       shift = min_delta;
     }
-    double decayFactor = FastMath.exp(-dist / 100.);
+    double decayFactor = Math.exp(-dist / 100.);
     float new_elevation_buffer = (float) ((elevation_buffer + shift) * decayFactor - shift);
     double incline = (elevation_buffer - new_elevation_buffer) / dist;
     elevation_buffer = new_elevation_buffer;
@@ -227,7 +225,7 @@ protected void computeKinematic(RoutingContext rc, double dist, double delta_h,
     double f_roll = rc.totalMass * GRAVITY * (rc.defaultC_r + incline);
     if (rc.footMode) {
       // Use Tobler's hiking function for walking sections
-      speed = rc.maxSpeed * FastMath.exp(-3.5 * Math.abs(incline + 0.05));
+      speed = rc.maxSpeed * Math.exp(-3.5 * Math.abs(incline + 0.05));
     } else if (rc.bikeMode) {
       speed = solveCubic(rc.S_C_x, f_roll, rc.bikerPower);
       speed = Math.min(speed, maxSpeed);