[Help] understand how the client shows the interface

[ADMTec]

hello, I was wondering if someone could explain to me how the MuOnline client does to read the interface images and assemble them ?? because I saw that many of the images of the new interface are DDS files after being converted and contain various parts of the interface in different positions!


as I couldn't find any source of main.exe from seasons above 8 I can't study the source to understand the same