0x4 Face Type Flag
Although the purpose of the 0x4 flag is unknown, it is used in almost every level. Both
JED and JkEdit assign the 0x4 flag to every visible surface. This is apparently
not what the flag was intended for. In the LEC levels that use this flag, you can almost
see a pattern in the surfaces that use it, but not every surface does use it. And in LEC
levels, this flag is sometimes assigned to adjoins.
Notably, the two SP narshaada levels do not use the 0x4 flag. So either the flag does
something and it's not important, or the flag has been abandoned.
The 0x4 Face Type Flag is cleared from every surface before startup.