Defines starting with `f' in src

• FASTDARK src/p_spec.h:179
• FATSPREAD src/p_enemy.c:1350
• FB src/wi_stuff.c:285
• FLOORSPEED src/p_spec.h:601
• FRICTION src/p_mobj.c:113
• FUZZOFF src/r_draw.c:261
• FUZZTABLE src/r_draw.c:260