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Routines |
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Used by the routines at ObjectPlacement_SpecialTerrain, InitialiseLevel, ContextualRandomNumber, 28829, InitialiseNewLevel and DemoModeInput.
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Random numbers are just data pulled from addresses between 30976-31487 (sequentially).
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| GetRandomNumber | 25600 | PUSH HL | Stash HL on the stack. | |||||
| 25601 | LD HL,(30750) | HL=*RandomNumberSeed. | ||||||
| 25604 | LD A,(HL) | A=*HL. | ||||||
| 25605 | INC L | Increment L by one. | ||||||
| 25606 | JR NZ,UpdateRandomNumberSeed | Jump to UpdateRandomNumberSeed if L is not zero. | ||||||
| 25608 | INC H | Increment H by one. | ||||||
| 25609 | BIT 2,H | Jump to UpdateRandomNumberSeed if bit 2 of H is not set. | ||||||
| 25611 | JR Z,UpdateRandomNumberSeed | |||||||
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Bit 2 is set, this means that H has reached 124 so pull the range back down to 121.
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| 25613 | LD H,121 | H=121. | ||||||
| UpdateRandomNumberSeed | 25615 | LD (30750),HL | Write HL to *RandomNumberSeed. | |||||
| 25618 | POP HL | Restore HL from the stack. | ||||||
| 25619 | RET | Return. | ||||||
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