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Routines |
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Tests a row against the view, using the position in the alternate registers. A row on the drawable page, with its column below C1 is drawn by TestBlockRow_Draw when it is before the patched row, or by DrawShortRow when it is on that row. A row past it is left undrawn.
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| TestBlockRow | C717 | PUSH HL | Take the position from the alternate registers. | |||||||
| C718 | PUSH DE | |||||||||
| C719 | EXX | |||||||||
| C71A | POP DE | |||||||||
| C71B | POP HL | |||||||||
| C71C | LD A,H | Return unless the row is on the drawable page. | ||||||||
| C71D | CP $80 | |||||||||
| C71F | RET NZ | |||||||||
| C720 | LD A,L | Return when the column is past C0. | ||||||||
| C721 | CP $C1 | |||||||||
| C723 | RET NC | |||||||||
| C724 | LD A,D | Return unless the other address is on the same page. | ||||||||
| C725 | CP $80 | |||||||||
| C727 | RET NZ | |||||||||
| C728 | LD A,E | A row on the patched position is the short row. | ||||||||
| C729 | SUB $00 | |||||||||
| C72B | JR Z,DrawShortRow | |||||||||
| C72D | RET NC | A row past that position is left undrawn. | ||||||||
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Continue on to TestBlockRow_Draw.
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| Prev: C704 | Up: Map | Next: C72E |