I can't find this file. I expected it would be a text file, since what I want is to set the size of the frame, nor the appearance of the model or the texture. Just the size.
-mapitems.gfx is in your ck2 directory/interface/ or do a search
-it is a text file. you can open it with notepad and such.
-it contains the size values for every "shield type" -arranged by religion and by tier.
in my Coa mod linked in my sig you can this file with increased size for county-level and duchy-level ; decreased size for muslim empires.