Mario: detect left/right collision

mario/mario_visitor.hpp

@@ -23,6 +23,12 @@ public:
     virtual void fromId( uint64_t id ) override {
         from = id;
     }
+    bool canGoLeft() {
+        return !left;
+    }
+    bool canGoRight() {
+        return !right;
+    }
 
 private:
     bool onGround = false;
@@ -30,6 +36,8 @@ private:
     bool stop = false;
     double newX;
     uint64_t from = -1;
+    bool left = false;
+    bool right = false;
 };
 
 #endif