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Routines |
| Prev: 61418 | Up: Map | Next: 61625 |
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Used when apply-horizontal-mirror flag is set
Used by the routine at 61415.
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| 61521 | LD A,(23449) | Increase pixel row counter... | ||||||||||||
| 61524 | DEC A | ... | ||||||||||||
| 61525 | AND 7 | ...and reset to 7 if it falls below zero... | ||||||||||||
| 61527 | LD (23449),A | ... | ||||||||||||
| 61530 | CP 7 | If new value of pixel row counter is 7 (i.e. we have rolled over to a new character block)... | ||||||||||||
| 61532 | JR Z,61537 | ...then advance HL to next character block to be drawn and return | ||||||||||||
| 61534 | DEC H | Decrease display file address by 256 bytes (i.e. move to next pixel row up) | ||||||||||||
| 61535 | XOR A | Set A to zero | ||||||||||||
| 61536 | RET | Return | ||||||||||||
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This next section advances HL to next character block to be drawn
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| 61537 | LD A,(23450) | Load A with apply-horizontal-mirror and apply-vertical-mirror flags | ||||||||||||
| 61540 | AND 1 | If apply-vertical-mirror flag is set... | ||||||||||||
| 61542 | JP NZ,61598 | ...then skip ahead to 61598 | ||||||||||||
| 61545 | PUSH BC | Store BC | ||||||||||||
| 61546 | LD A,(23444) | Load x-coordinate of character block currently being drawn into A... | ||||||||||||
| 61549 | INC A | ...increase by one... | ||||||||||||
| 61550 | LD B,A | ...and load into B | ||||||||||||
| 61551 | LD A,(23410) | Load (x-coordinate + 1) of right of graphic being drawn into A | ||||||||||||
| 61554 | CP B | If both x-coordinates are the same (i.e. we have moved beyond graphic's right edge)... | ||||||||||||
| 61555 | JR Z,61575 | ...then jump to 61575 | ||||||||||||
| 61557 | LD A,B | Store increased x-coordinate at 23444... | ||||||||||||
| 61558 | LD (23444),A | ... | ||||||||||||
| 61561 | LD BC,(23444) | Load BC with coordinates of new character block to draw | ||||||||||||
| 61565 | CALL 63203 | Move virtual cursor (bitmap) to display file address for coordinates x=C, y=B and load address into HL | ||||||||||||
| 61568 | LD A,7 | Advance HL down seven pixel rows to bottom of character block... | ||||||||||||
| 61570 | ADD A,H | ... | ||||||||||||
| 61571 | LD H,A | ... | ||||||||||||
| 61572 | XOR A | Set A to zero | ||||||||||||
| 61573 | POP BC | Restore BC | ||||||||||||
| 61574 | RET | Return | ||||||||||||
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This next section advances HL to next character row to be drawn
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| 61575 | LD A,(23408) | Load A with x-coordinate of left of graphic to draw... | ||||||||||||
| 61578 | LD (23444),A | ...and set current x-coordinate to match | ||||||||||||
| 61581 | LD A,(23445) | Load current y-coordinate into C, decreasing by one... | ||||||||||||
| 61584 | DEC A | ... | ||||||||||||
| 61585 | LD C,A | ... | ||||||||||||
| 61586 | LD A,(23409) | Load y-coordinate of top of graphic being drawn into A | ||||||||||||
| 61589 | CP C | If both y-coordinates are the same (i.e. we have moved beyond graphic's top edge)... | ||||||||||||
| 61590 | JR Z,61489 | ...then jump to 61489 (load A with 1, reset zero flag and return) | ||||||||||||
| 61592 | LD A,C | Store increased y-coordinate at 23445... | ||||||||||||
| 61593 | LD (23445),A | ... | ||||||||||||
| 61596 | JR 61561 | Move virtual cursor (bitmap) to display file address for coordinates x=C, y=B and load address into HL then return | ||||||||||||
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This next section advances HL to next character block to be drawn where the apply-vertical-mirror flag is set
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| 61598 | PUSH BC | Store BC | ||||||||||||
| 61599 | LD A,(23444) | Load x-coordinate of character block currently being drawn into A... | ||||||||||||
| 61602 | DEC A | ...decrease by one... | ||||||||||||
| 61603 | LD B,A | ...and load into B | ||||||||||||
| 61604 | LD A,(23408) | Load x-coordinate of left of graphic being drawn into A... | ||||||||||||
| 61607 | DEC A | ...and decrease by one | ||||||||||||
| 61608 | CP B | If both x-coordinates are the same (i.e. we have moved beyond graphic's left edge)... | ||||||||||||
| 61609 | JR Z,61618 | ...then jump to 61618 | ||||||||||||
| 61611 | LD A,B | Store decreased x-coordinate at 23444... | ||||||||||||
| 61612 | LD (23444),A | ... | ||||||||||||
| 61615 | JP 61561 | Move virtual cursor (bitmap) to display file address for coordinates x=C, y=B and load address into HL then return | ||||||||||||
| 61618 | LD A,(23410) | Load x-coordinate of right of graphic being drawn into A... | ||||||||||||
| 61621 | DEC A | ... | ||||||||||||
| 61622 | JP 61578 | Move current character position down one character row and return | ||||||||||||
| Prev: 61418 | Up: Map | Next: 61625 |