PHP conditional to check which category/subcategory I'm in

[btw6391]

Similar to something like <!-- IF !isTopicOrMain --> or <!-- IF !isEditing -->, is there some variable I can check in my .tpl file to see which category or subcategory I'm in?

I'm building out a custom composer that changes based on where the topic is being posted. For instance, it would know that I'm currently in the "NodeBB Plugins" category and display a particular part of my .tpl file, otherwise it wouldn't.