| Routines

26068: Check whether a character is beside a chair

Used by the routines at 26263, 31092 and 62460. The value returned in A is as follows:
A | Meaning
--- | ---
0 | Character is facing left and standing beside a chair
3 | Character must walk to the next chair to the left
4 | Character must walk to the rightmost chair
255 | Character is not in a classroom
Input
H | Character number (183-210)
26068 | LD L,2 | Point HL at byte 2 of the character's buffer
26070 | LD A,(HL) | A=character's y-coordinate
26071 | LD DE,54066 | The table at 54066 contains the x-coordinates of the left ends of the classrooms
26074 | LD B,3 | There are three sets of chairs on the top floor
26076 | CP B | Is the character on the top floor?
26077 | JR Z,26086 | Jump if so
26079 | DEC B | B=2 (two sets of chairs on the middle floor)
26080 | CP 10 | Is the character on the middle floor?
26082 | JR NZ,26101 | Jump if not
26084 | LD E,53 | DE=54069
26086 | DEC L |
26087 | LD A,(HL) | A=character's x-coordinate
26088 | EX DE,HL | HL=54066 if the character is on the top floor, 54069 if he's on the middle floor
26089 | CP (HL) | Is the character to the left of this classroom?
26090 | JR C,26097 | Jump if so
26092 | INC H | Point HL at the x-coordinate of the right end of the classroom (in the table at 54322)
26093 | CP (HL) | Is the character in this classroom?
26094 | JR C,26104 | Jump if so
26096 | DEC H |
26097 | INC L |
26098 | DJNZ 26089 |
26100 | EX DE,HL |
26101 | LD A,255 | Signal: the character is not in a classroom
26103 | RET |
The character is in a classroom. But is he beside a chair?
26104 | INC H | Point HL at the x-coordinate of the leftmost seat in the classroom (in the table at 54578)
26105 | CP (HL) | Is the character to the right of the leftmost chair?
26106 | JR NC,26112 | Jump if so
26108 | LD A,4 | Signal: the character must walk to the rightmost chair
26110 | EX DE,HL |
26111 | RET |
26112 | INC H | Point HL at the x-coordinate of the rightmost seat in the classroom (in the table at 54834)
26113 | CP (HL) | Is the character to the left of the rightmost chair?
26114 | JR C,26120 | Jump if so
26116 | LD A,3 | Signal: the character must walk to the next chair to the left
26118 | EX DE,HL |
26119 | RET |
The character is between the leftmost and rightmost chairs in the classroom.
26120 | DEC E | E=0
26121 | LD A,(DE) | A=character's animatory state
26122 | INC E | E=1
26123 | RLCA |
26124 | JR C,26108 | Jump if the character is facing right
26126 | LD A,(DE) | A=character's x-coordinate
26127 | XOR (HL) | The chairs in a classroom have either all odd or all even x-coordinates; is the character standing beside one?
26128 | RRCA
26129 | JR NC,26116 | Jump if not
26131 | EX DE,HL |
26132 | XOR A | Signal: the character is facing left and standing beside a chair
26133 | RET |
The contents of the classroom/chairs location tables are as follows:
Room | Chairs
--- | ---
0 | 23 | 11 | 22 | Blue Room
40 | 63 | 50 | 61 | Yellow Room
159 | 180 | 168 | 179 | Top-floor room in the girls' skool
30 | 54 | 40 | 53 | Science Lab
159 | 179 | 167 | 178 | Middle-floor room in the girls' skool