From 860d31d8fb5735da9ed347733ac017b81d4b8272 Mon Sep 17 00:00:00 2001
From: Arne Keller <arne.keller01@yahoo.de>
Date: Wed, 4 Mar 2020 20:17:03 +0100
Subject: [PATCH] Recompute train direction when needed

---
 src/edu/kit/informatik/model/Train.java       | 20 ++-----------------
 .../kit/informatik/model/TrainManager.java    |  2 --
 2 files changed, 2 insertions(+), 20 deletions(-)

diff --git a/src/edu/kit/informatik/model/Train.java b/src/edu/kit/informatik/model/Train.java
index 86631c6..2b9f573 100644
--- a/src/edu/kit/informatik/model/Train.java
+++ b/src/edu/kit/informatik/model/Train.java
@@ -31,10 +31,6 @@ public final class Train {
      * positions when moving the train.
      */
     private LinkedList<Vector2D> position;
-    /**
-     * Direction of the train head.
-     */
-    private Vector2D direction;
     /**
      * Set of rails this train occupies.
      */
@@ -197,7 +193,6 @@ public final class Train {
         }).collect(Collectors.toSet());
 
         this.position = positions;
-        this.direction = rawDirection.normalized();
         this.occupiedRails = occupiedRailsSet;
 
         return true;
@@ -207,7 +202,7 @@ public final class Train {
      * @return whether this train is placed on a rail network
      */
     public boolean isPlaced() {
-        return position != null && direction != null && occupiedRails != null;
+        return position != null && occupiedRails != null;
     }
 
     /**
@@ -250,7 +245,7 @@ public final class Train {
      */
     public Vector2D getDirection() {
         // make sure caller can not modify internal state
-        return new Vector2D(direction);
+        return position.get(0).subtract(position.get(1));
     }
 
     /**
@@ -341,22 +336,11 @@ public final class Train {
         } // else: only touching new rail
     }
 
-    /**
-     * Update the direction of this train.
-     *
-     * @param newDirection new direction of the train
-     */
-    public void setDirection(final Vector2D newDirection) {
-        // make sure the caller can not modify internal data afterwards
-        direction = new Vector2D(newDirection);
-    }
-
     /**
      * Remove this train from the rail network.
      */
     public void removeFromRails() {
         position = null;
-        direction = null;
         occupiedRails = null;
     }
 
diff --git a/src/edu/kit/informatik/model/TrainManager.java b/src/edu/kit/informatik/model/TrainManager.java
index 9ec9326..bb3cb9f 100644
--- a/src/edu/kit/informatik/model/TrainManager.java
+++ b/src/edu/kit/informatik/model/TrainManager.java
@@ -280,7 +280,6 @@ public final class TrainManager {
                 collisions.add(new HashSet<>(Arrays.asList(train)));
             } else {
                 train.moveTo(railNetwork, nextPosition);
-                train.setDirection(direction);
             }
         });
         getStaticCollisions(collisions);
@@ -306,7 +305,6 @@ public final class TrainManager {
                 collisions.add(new HashSet<>(Arrays.asList(train)));
             } else {
                 train.moveBackTo(railNetwork, nextPosition);
-                train.setDirection(front.subtract(train.getFrontPosition()));
             }
         });
         getStaticCollisions(collisions);