| Routines

F4FA: Open the lip of the speech bubble

Used by the routine at 734E. Removes the solid line above the lip of the speech bubble, thus 'opening' it.
Input
DE | Coordinates of the speech bubble lip
F4FA | LD A,E | UDG references 0xF8-0xFF correspond to the 8 UDGs that make up the bottom half of the speech bubble; set E to the reference of the UDG that is above the lip
F4FB | AND $07
F4FD | ADD A,$F8
F4FF | LD E,A
F500 | LD C,$03 | We need to adjust the UDGs for each third of the skool
F502 | LD H,$7F |
F504 | LD B,$08 | 8 UDGs make up the bottom half of the speech bubble
F506 | LD A,H | Point HL at the bottom pixel row of the UDG for the bottom-left corner of the speech bubble
F507 | ADD A,B
F508 | LD H,A
F509 | LD A,E
F50A | LD L,$F8
F50C | LD (HL),$7E | Open the bottom edge (0x81=10000001) of this speech bubble UDG if the lip is underneath, or close it (0x7E=01111110) otherwise
F50E | CP L
F50F | JR NZ,$F513
F511 | LD (HL),$81
F513 | INC L | Move HL to the next UDG along the bottom of the speech bubble
F514 | DJNZ $F50C | Jump back until the lip is open and the others are closed
F516 | DEC C | Next third of the skool
F517 | JR NZ,$F504 | Jump back until the UDGs for each third of the skool have been modified
F519 | JP $72D2 | Update the SRB for the middle 6 UDG columns of the bubble