Would like to check if lasso selection of the map component be a filter? Meaning to say that I can mark an area to only show the data at that particular piece of land as my "format" so that even if i upload new source to this file, I'm able to view data from the marked up area.
Lasso selection can work as action filter during user interaction.
The manual selection is temporary.
So if you want to save the selection, custom view is the feature to use.
Assume that you have a Tableau Server.