Add some stats & fix bird being able to go out of screen at the top

GameScreen.java

@@ -6,22 +6,37 @@ class GameScreen
     private final List<Drawable> _drawables;
     private final Bird _bird;
     private final Welt _welt;
+    private double _totalTime;
+    private int _try;
 
     public GameScreen()
     {
         _drawables = new ArrayList<Drawable>();
         _bird = new Bird(this);
         _welt = new Welt(this);
+        _totalTime = 0;
+        _try = 1;
     }
 
+    /*
+     * Elapsed time is expected to be in ms
+     */
     public void update(double elapsed)
     {
         _bird.update(elapsed);
         _welt.update(elapsed);
+        _totalTime += elapsed;
+        System.out.print("\r" + _try + " - Time survived: " + (int)(_totalTime * 1e-3) + "s, " +
+                "speed: " + (int)_welt.getSpeed() + "px/s");
 
-        if (_welt.checkCollision(_bird.getRect()) ||
+        Rectangle birdRect = _bird.getRect();
-                _bird.getRect().getY() + _bird.getRect().getHeight() > TurtleWelt.HEIGHT)
+        if (_welt.checkCollision(_bird.getRect())
+                || birdRect.getY() + birdRect.getHeight() > TurtleWelt.HEIGHT
+                || birdRect.getY() + birdRect.getHeight() < 0)
         {
+            System.out.print("\n");
+            ++_try;
+            _totalTime = 0;
             _bird.reset();
             _welt.reset();
         }

Welt.java

@@ -83,4 +83,9 @@ class Welt implements Drawable
             }
         }
     }
+
+    public double getSpeed()
+    {
+        return _speed;
+    }
 }