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Routines |
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Used by the routine at PopulateRoomBuffer.
Sets the room data pointer for the current room.
The room data is stored as a series of blocks from Room01, separated by 0 terminators. This routine scans through the data to find the block matching the *CurrentRoom.
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| FindRoomData | 24518 | LD A,(24517) | D=*CurrentRoom. | |
| 24521 | LD D,A | |||
| 24522 | LD E,1 | E=1 (start searching from room 1). | ||
| 24524 | CP E | Return if the current room is 1 (the data pointer already defaults to the first room). | ||
| 24525 | RET Z | |||
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Scan through the room data blocks. Each block is terminated by 0 so count terminators to find the Nth room.
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| 24526 | LD HL,33706 | HL=33706 (start of room data + 1 for no real reason). | ||
| FindRoomData_ScanLoop | 24529 | LD A,(HL) | A=*HL. | |
| 24530 | INC HL | Advance the data pointer. | ||
| 24531 | OR A | Jump to FindRoomData_FoundTerminator if a 0 terminator was found. | ||
| 24532 | JR Z,FindRoomData_FoundTerminator | |||
| 24534 | JR FindRoomData_ScanLoop | Jump to FindRoomData_ScanLoop to keep scanning. | ||
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Found a block terminator so check if we've reached the target room.
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| FindRoomData_FoundTerminator | 24536 | INC E | Increment the room counter in E. | |
| 24537 | LD A,E | Jump to Raise_Table_Error if the room counter has exceeded 17 (maximum number of rooms/room not found). | ||
| 24538 | CP 17 | |||
| 24540 | JR NC,Raise_Table_Error | |||
| 24542 | CP D | Jump to FindRoomData_Found if the room counter matches the target room number. | ||
| 24543 | JR Z,FindRoomData_Found | |||
| 24545 | JR FindRoomData_ScanLoop | Otherwise, jump to FindRoomData_ScanLoop to keep scanning. | ||
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The target room was found so store the pointer to its data.
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| FindRoomData_Found | 24547 | LD (24515),HL | Write HL to *PointerRoomData. | |
| 24550 | RET | Return. | ||
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