code: function (event) {
          if (this.released === false) {
              var x = event.gameScreenX + (event.width / 2);
              var y = event.gameScreenY + (event.height / 2);
              // pointerMove is a global on the viewport, so check for coordinates
              if (this.getBounds().containsPoint(x, y)) {
                  // if any direction is active, update it if necessary
                  if (this.cursors.left === true || this.cursors.right === true) {
                      this.checkDirection.call(this, x, y);
                  }
              } else {
                  // release keys/joypad if necessary
                  this.onRelease.call(this, event);
              }
          }
      }
docs: pointermove function