How to determine subcategory in vBulletin

[SiteTalkZone]

I create a structure forum on my host as following:

1. Main Category 
          1.1 - Forum
                    1.1.1 - Forum
                    1.1.2 - Category
          1.2 - Category
                    1.2.1 - Forum
                    1.2.2 - Category

When I display the forum, icon of category and icon of forum is same as together.

I found and customize template for displaying forum and use bit cancontainthreads: $foruminfo[cancontainthreads] to check which forum is act as forum or act as category.

However, it seems to effect to level 1.1 & 1.2 (in above structure).
I tried to edit icon's link in forumhome_subforumbit_nopost (for category) and forumhome_subforumbit_post (for forum) but it's nothing to change.

So how to determine which sub-forum (level 1.1.1, 1.1.2, 1.2.1, 1.2.2) is act as forum or act as category.


Thanks!