This fixes how removing certain flags (such as FF_EXISTS) from FOFs can cause HOMs on walls bordering their target sectors. Also fixes how the force-FOF-to-vanish linedef special can leave behind the FOF's shadow
This is not how you use pushlstring! This is actually sending uninitialized memory to Lua, which is making scripts have inconsistent results (duh?)
c/o JTE: "Tell Red they're a doofus."
tmthing must not be set outside of P_MapStart and P_MapEnd
or the game will fail a sanity check which ensures that
mobj references are not persistent across frames and crash.
Angles now go from 0 to 0xFFFF (360 degrees == FRACUNIT) instead
of using a full UINT32. Lua only has one number type, so signedness
gets in the way of using angle_t directly. This handling of angles
matches up with how ZDoom ACS scripting and the like does it.
I also changed all the integer casts and pushes of fixed_t to
their own macro in preperation for possible future seperation.
