fix: overlay 离线版链接处理

src/sdk/cover/index.js

@@ -2722,7 +2722,7 @@ function load4dkkMedias(model){//加载四维看看的一些媒体物品
                     //prop.url =  location.origin + '/oss/scene_view_data/'+ model.props.raw.num + '/user/'+prop.url,
                     prop.url = sceneJsonPath.replace('data/scene.json','user/'+prop.url)  //offline different
 
-                    if(!prop.url.substr(0,5).includes('http')) prop.url = location.origin + prop.url
+                    if(!prop.url.substr(0,5).includes('http')) prop.url = Potree.Common.joinUrl(location.origin, prop.url)