From 480977ec464697195ce1a9caca99a0a2a91e845c Mon Sep 17 00:00:00 2001
From: quaelnix <122357328+quaelnix@users.noreply.github.com>
Date: Wed, 8 Feb 2023 22:01:09 +0100
Subject: [PATCH] Fix regression in travel time computation

abrensch@17be365 introduced a bug that causes a negative bias in the calculated incline each time the elevation buffer is reset, which results in an additional misestimation of the travel time when via points are added.
---
 brouter-core/src/main/java/btools/router/StdPath.java | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/brouter-core/src/main/java/btools/router/StdPath.java b/brouter-core/src/main/java/btools/router/StdPath.java
index b890c27..71ed848 100644
--- a/brouter-core/src/main/java/btools/router/StdPath.java
+++ b/brouter-core/src/main/java/btools/router/StdPath.java
@@ -177,13 +177,11 @@ final class StdPath extends OsmPath {
 
   private double calcIncline(double dist) {
     double min_delta = 3.;
-    double shift;
+    double shift = 0.;
     if (elevation_buffer > min_delta) {
       shift = -min_delta;
-    } else if (elevation_buffer < min_delta) {
-      shift = -min_delta;
-    } else {
-      return 0.;
+    } else if (elevation_buffer < -min_delta) {
+      shift = min_delta;
     }
     double decayFactor = FastMath.exp(-dist / 100.);
     float new_elevation_buffer = (float) ((elevation_buffer + shift) * decayFactor - shift);