code: function (action /*, keyCode, edge */) {
  
          // navigate the map :)
          if (action === "left") {
              me.game.viewport.move(-(me.levelDirector.getCurrentLevel().tilewidth / 2), 0);
  
          } else if (action === "right") {
              me.game.viewport.move(me.levelDirector.getCurrentLevel().tilewidth / 2, 0);
          }
  
          if (action === "up") {
              me.game.viewport.move(0, -(me.levelDirector.getCurrentLevel().tileheight / 2));
  
          } else if (action === "down") {
              me.game.viewport.move(0, me.levelDirector.getCurrentLevel().tileheight / 2);
          }
  
          if (action === "enter") {
              me.game.viewport.shake(16, 500);
          }
  
          // force redraw
          me.game.repaint();
  
      }
docs: update function