bugfix

packages/artplayer/src/player/flipMix.js

@@ -7,7 +7,7 @@ export default function flipMix(art, player) {
 
   Object.defineProperty(player, 'flip', {
     value: dir => {
-      const dirList = ['horizontal', 'vertical'];
+      const dirList = ['normal', 'horizontal', 'vertical'];
       errorHandle(dirList.includes(dir), `The 'angle' need to be one of '[horizontal, vertical]', but got ${dir}`);
       art.refs.$player.dataset.flip = dir;
     }