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Routines |
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This waves the morale flag up and down.
Used by the routines at main_loop and menu_screen.
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| wave_morale_flag | A035 | LD HL,$A12F | Point HL at the game counter | |
| A038 | INC (HL) | Increment the game counter in-place | ||
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Wave the flag on every other turn.
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| A039 | LD A,(HL) | Now fetch the game counter | ||
| A03A | AND $01 | Is its bottom bit set? | ||
| A03C | RET NZ | Return if so | ||
| A03D | PUSH HL | Save the game counter pointer | ||
| A03E | LD A,($A13C) | Fetch morale | ||
| A041 | LD HL,$A140 | Point HL at currently displayed morale | ||
| A044 | CP (HL) | Is the currently displayed morale different to the actual morale? | ||
| A045 | JR Z,wave_morale_flag_2 | It's equal - jump straight to wiggling the flag | ||
| A047 | JP NC,wave_morale_flag_0 | Actual morale exceeds displayed morale - jump to the increasing case | ||
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Decreasing morale.
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| A04A | DEC (HL) | Decrement displayed morale | ||
| A04B | LD HL,($A141) | Get the current screen address of the morale flag | ||
| A04E | CALL next_scanline_down | Given a screen address, return the same position on the next scanline down | ||
| A051 | JR wave_morale_flag_1 | Jump over increasing morale block | ||
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Increasing morale.
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| wave_morale_flag_0 | A053 | INC (HL) | Increment displayed morale | |
| A054 | LD HL,($A141) | Get the current screen address of the morale flag | ||
| A057 | CALL next_scanline_up | Given a screen address, returns the same position on the next scanline up | ||
| wave_morale_flag_1 | A05A | LD ($A141),HL | Set the screen address of the morale flag | |
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Wiggle and draw the flag.
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| wave_morale_flag_2 | A05D | LD DE,$DA6B | Point DE at bitmap_flag_down | |
| A060 | POP HL | Restore the game counter pointer | ||
| A061 | BIT 1,(HL) | Is bit 1 set? | ||
| A063 | JR Z,wave_morale_flag_3 | Skip next instruction if not | ||
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Note that the last three rows of the bitmap_flag_up bitmap overlap with the first three of the bitmap_flag_down bitmap.
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| A065 | LD DE,$DA29 | Point DE at bitmap_flag_up | ||
| wave_morale_flag_3 | A068 | LD HL,($A141) | Get the screen address of the morale flag | |
| A06B | LD BC,$0319 | Plot the flag always at 24x25 pixels in size | ||
| A06E | JP plot_bitmap | Exit via plot_bitmap | ||
| Prev: A01A | Up: Map | Next: A071 |