added turret button

Assets/Prefabs/Turret.prefab.meta

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Assets/Scripts/Turret.cs

@@ -3,13 +3,10 @@ using System.Collections;
 
 public class Turret : MonoBehaviour {
 
-    public Transform target;
     public GameObject rocketPrefab;
+    private Transform target;
+    private Rocket currentRocket;
 
-    // Use this for initialization
-    void Start () {
-        InvokeRepeating("shoot", 1.0f, 2.0f);
-    }
     
     // Update is called once per frame
     void Update () {
@@ -26,7 +23,9 @@ public class Turret : MonoBehaviour {
 
     public void shoot()
     {
-        Rocket newRocket = (GameObject.Instantiate(rocketPrefab, transform.position, transform.rotation) as GameObject).GetComponent<Rocket>();
-        newRocket.setTarget(target);
+        if (currentRocket) return; // do not shoot another rocket when there is one already flying.
+
+        currentRocket = (GameObject.Instantiate(rocketPrefab, transform.position, transform.rotation) as GameObject).GetComponent<Rocket>();
+        currentRocket.setTarget(target);
     }
 }

Assets/Scripts/TurretButton.cs

+using UnityEngine;
+using System.Collections;
+
+public class TurretButton : MonoBehaviour {
+
+    public Turret cannon; // die entsprechende turret-cannon.
+
+    void OnCollisionEnter2D(Collision2D coll)
+    {
+        //soll nur von oben ausloesen:
+        if (coll.gameObject.tag == "Player" && coll.relativeVelocity.x<0.001f && coll.relativeVelocity.y>0.2f)
+        {
+            cannon.setTarget(coll.gameObject.transform);
+            cannon.shoot();
+        }
+    }
+}

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