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Routines |
| Prev: D651 | Up: Map | Next: D6A4 |
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The previous routine has determined that it's time for a warlock to appear in the room.
As long as this level's warlock hasn't been destroyed, the routine sets the warlock's screen position, movement direction, and speed.
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| D67B | LD A,B | Get warlock number (between 1 and 7 from table at 6C7C) | ||||||
| D67C | CALL $E16A | Set up warlock data in working buffer at EB43 | ||||||
| D67F | LD HL,$EAF6 | Get address holding the room's vertical pixel position | ||||||
| D682 | INC HL | Held in next (high) byte, so advance one address | ||||||
| D683 | LD A,(HL) | Get the room position byte (top of room) | ||||||
| D684 | ADD A,$1C | Add 28 pixels - the warlock's vertical position remains the same, even as it floats across the screen between the side and back walls | ||||||
| D686 | LD ($EB4A),A | Store this value as the warlock's vertical pixel position | ||||||
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Determine warlock's (horizontal) speed and direction. Values can be between -3 and +4. A value of 0 means the warlock stays in one place.
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| D689 | AND $07 | The A register contains the vertical room pixel position, used here to provide the variety for the warlock's movement. Keep bits 0-2 (values 0-7) | ||||||
| D68B | SUB $03 | Subtract 3, to give a possible values of -3 to +4 (negative numbers = left, positive numbers = right) | ||||||
| D68D | LD ($EB4C),A | Store as warlock's (horizontal) speed (and direction) | ||||||
| D690 | LD HL,($EB44) | Address pointer to this warlock's data set (at 6C7C) | ||||||
| D693 | INC HL | |||||||
| D694 | LD A,(HL) | Get the second byte of the warlock's data set | ||||||
| D695 | CP $00 | |||||||
| D697 | JR NZ,$D6CF | The second byte tells us if the warlock is still alive on this level. If this byte ISN'T 0, it means Maroc has destroyed it, so jump out of the routine here if this is the case | ||||||
| D699 | INC HL | Move the address pointer along to the sixth byte of the warlock's data set. | ||||||
| D69A | INC HL | |||||||
| D69B | INC HL | |||||||
| D69C | INC HL | |||||||
| D69D | LD A,(HL) | This is this warlock's "aggression" stat, which affects - the likelihood of it appearing - the frequency of missiles being fired |
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| D69E | LD ($EBAD),A | Store in warlock active data buffer | ||||||
| D6A1 | JP $D6B0 | |||||||
| Prev: D651 | Up: Map | Next: D6A4 |