basic gravity working through effects

[physics.git] / src / Effects / Gravity.h

diff --git a/src/Effects/Gravity.h b/src/Effects/Gravity.h
index f6dd459..dc04726 100644 (file)
--- a/src/Effects/Gravity.h
+++ b/src/Effects/Gravity.h
@@ -9,11 +9,11 @@ class Gravity: public Effect
 {
   public:
     Gravity();
-    ~Gravity();
+    virtual ~Gravity();
 
-    Vector2 positionDelta(const PhysicsEntity*, float);
-    Vector2 velocityDelta(const PhysicsEntity*, float);
-    Vector2 forceDelta(const PhysicsEntity*, float);
+    Vector2 positionDelta(const PhysicsEntity*, float) const;
+    Vector2 velocityDelta(const PhysicsEntity*, float) const;
+    Vector2 forceDelta(const PhysicsEntity*, float) const;
 };
 
 #endif // GRAVITY_H