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Routines |
| Prev: 61415 | Up: Map | Next: 61521 |
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Used when apply-horizontal-mirror flag is reset
Used by the routine at 61415.
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| 61418 | LD A,(23449) | Increase pixel row counter... | ||||||||||||
| 61421 | INC A | ... | ||||||||||||
| 61422 | AND 7 | ...and reset to zero if it exceeds 7... | ||||||||||||
| 61424 | LD (23449),A | ... | ||||||||||||
| 61427 | JR Z,61432 | If we have rolled over to a new character block then advance HL to next character block to be drawn and return | ||||||||||||
| 61429 | INC H | Increase display file address by 256 bytes (i.e. move to next pixel row down) | ||||||||||||
| 61430 | XOR A | Set A to zero | ||||||||||||
| 61431 | RET | Return | ||||||||||||
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This next section advances HL to next character block to be drawn
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| 61432 | LD A,(23450) | Load A with apply-horizontal-mirror and apply-vertical-mirror flags | ||||||||||||
| 61435 | AND 1 | If apply-vertical-mirror flag is set... | ||||||||||||
| 61437 | JP NZ,61494 | ...then skip ahead to 61494 | ||||||||||||
| 61440 | PUSH BC | Store BC | ||||||||||||
| 61441 | LD A,(23444) | Load x-coordinate of character block currently being drawn into A... | ||||||||||||
| 61444 | INC A | ...increase by one... | ||||||||||||
| 61445 | LD B,A | ...and load into B | ||||||||||||
| 61446 | LD A,(23410) | Load (x-coordinate + 1) of right of graphic being drawn into A | ||||||||||||
| 61449 | CP B | If both x-coordinates are the same (i.e. we have moved beyond graphic's right edge)... | ||||||||||||
| 61450 | JR Z,61466 | ...then jump to 61466 | ||||||||||||
| 61452 | LD A,B | Store increased x-coordinate at 23444... | ||||||||||||
| 61453 | LD (23444),A | ... | ||||||||||||
| 61456 | LD BC,(23444) | Load BC with coordinates of new character block to draw | ||||||||||||
| 61460 | CALL 63203 | Move virtual cursor (bitmap) to display file address for coordinates x=C, y=B and load address into HL | ||||||||||||
| 61463 | XOR A | Set A to zero | ||||||||||||
| 61464 | POP BC | Restore BC | ||||||||||||
| 61465 | RET | Return | ||||||||||||
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This next section advances HL to next character row to be drawn
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| 61466 | LD A,(23408) | Load A with x-coordinate of left of graphic to draw... | ||||||||||||
| 61469 | LD (23444),A | ...and set current x-coordinate to match | ||||||||||||
| 61472 | LD A,(23445) | Load current y-coordinate into C, increasing by one... | ||||||||||||
| 61475 | INC A | ... | ||||||||||||
| 61476 | LD C,A | ... | ||||||||||||
| 61477 | LD A,(23411) | Load (y-coordinate + 1) of bottom of graphic being drawn into A | ||||||||||||
| 61480 | CP C | If both y-coordinates are the same (i.e. we have moved beyond graphic's bottom edge)... | ||||||||||||
| 61481 | JR Z,61489 | ...then skip ahead to 61489 | ||||||||||||
| 61483 | LD A,C | Store increased y-coordinate at 23445... | ||||||||||||
| 61484 | LD (23445),A | ... | ||||||||||||
| 61487 | JR 61456 | 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 entry point is used by the routine at 61521.
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| 61489 | LD A,1 | Load A with 1 | ||||||||||||
| 61491 | OR A | Reset zero flag | ||||||||||||
| 61492 | POP BC | Restore BC | ||||||||||||
| 61493 | RET | 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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| 61494 | PUSH BC | Store BC | ||||||||||||
| 61495 | LD A,(23444) | Load x-coordinate of character block currently being drawn into A... | ||||||||||||
| 61498 | DEC A | ...decrease by one... | ||||||||||||
| 61499 | LD B,A | ...and load into B | ||||||||||||
| 61500 | LD A,(23408) | Load x-coordinate of left of graphic being drawn into A... | ||||||||||||
| 61503 | DEC A | ...and decrease by one | ||||||||||||
| 61504 | CP B | If both x-coordinates are the same (i.e. we have moved beyond graphic's left edge)... | ||||||||||||
| 61505 | JR Z,61514 | ...then jump to 61514 | ||||||||||||
| 61507 | LD A,B | Store decreased x-coordinate at 23444... | ||||||||||||
| 61508 | LD (23444),A | ... | ||||||||||||
| 61511 | JP 61456 | Move virtual cursor (bitmap) to display file address for coordinates x=C, y=B and load address into HL then return | ||||||||||||
| 61514 | LD A,(23410) | Load x-coordinate of right of graphic being drawn into A... | ||||||||||||
| 61517 | DEC A | ... | ||||||||||||
| 61518 | JP 61469 | Move current character position down one character row and return | ||||||||||||
| Prev: 61415 | Up: Map | Next: 61521 |