Mario: prepartations for multiple moving objects

mario/visitors/bounce_visitor.cpp

@@ -0,0 +1,17 @@
+#include "bounce_visitor.hpp"
+#include "../../sdlpp/sdlpp_renderobject.hpp"
+#include "../objectids.hpp"
+
+void BounceVisitor::visit( const SDLPP::RenderObject &obj ) {
+    auto id = obj.getId();
+    switch ( id ) {
+    case FLOOR_ID:
+    case BRICK_ID:
+    case BRICK_TOP_ID:
+        if(from == BOUNCE_COLLISION) {
+            hits += 1;
+        }
+    default:
+        break;
+    }
+}