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Routines |
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Used by the routine at Update_Task_Three_Entities.
Update Task Three Helpers for the current Thing Upstairs task.
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| Update_Task_Three_Helpers | C65C | LD IX,$8F13 | Point IX at the first Slimies entity (StateData_Complex_03). | |
| C660 | LD DE,$000E | Each entity record is 000E bytes long, then load that length into DE. | ||
| C663 | LD B,$04 | Load B with 04 as a loop counter. | ||
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Scan each upstairs helper: skip inactive / low slots, then randomly wander, climb, or drop a room.
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| Update_Task_Three_Helpers_Scan | C665 | PUSH BC | Stash BC on the stack. | |
| C666 | LD A,(IX+$01) | Load A with the current entity's flags byte 1. | ||
| C669 | AND %11100000 | Keep only the top bits E0 of the flag/coordinate in A. | ||
| C66B | JR NZ,Update_Task_Three_Helpers_AdvanceSlot | If the result was non-zero, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C66D | LD A,(IX+$06) | Load A with the current entity's y-extent. | ||
| C670 | CP $22 | Is the current entity's y-extent less than 22? If so, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C672 | JR C,Update_Task_Three_Helpers_AdvanceSlot | |||
| C674 | BIT 7,(IX+$00) | Is bit 07 of the current entity's entity type set? If not, call Update_Task_Three_Helpers_MaybeSetFlagBit2. | ||
| C678 | CALL Z,Update_Task_Three_Helpers_MaybeSetFlagBit2 | |||
| C67B | LD A,$15 | Load A with 15. | ||
| C67D | CALL PseudoRandom | Call PseudoRandom to pick a pseudo-random value. | ||
| C680 | OR A | Is 15 zero? If so, jump to Update_Task_Three_Helpers_ClearTypeBit7. | ||
| C681 | JR Z,Update_Task_Three_Helpers_ClearTypeBit7 | |||
| C683 | CP $06 | Is 15 less than 06? If so, jump to Update_Task_Three_Helpers_TryMoveLeft. | ||
| C685 | JR C,Update_Task_Three_Helpers_TryMoveLeft | |||
| C687 | CP $0B | Is 15 less than 0B? If so, jump to Update_Task_Three_Helpers_TryMoveRight. | ||
| C689 | JR C,Update_Task_Three_Helpers_TryMoveRight | |||
| C68B | CP $10 | Is 15 less than 10? If so, jump to Update_Task_Three_Helpers_MoveRoomDown. | ||
| C68D | JR C,Update_Task_Three_Helpers_MoveRoomDown | |||
| C68F | LD A,(IX+$04) | Load A with the current entity's room index. | ||
| C692 | CP $05 | Is the current entity's room index equal to 05? If so, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C694 | JR Z,Update_Task_Three_Helpers_AdvanceSlot | |||
| C696 | INC (IX+$05) | Move this entity one character down. | ||
| C699 | INC (IX+$06) | |||
| C69C | INC (IX+$04) | Advance this entity into the next room. | ||
| C69F | JR Update_Task_Three_Helpers_AdvanceSlot | Jump to Update_Task_Three_Helpers_AdvanceSlot to advance to the next helper entity. | ||
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Move this helper up one room (unless already in room 01).
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| Update_Task_Three_Helpers_MoveRoomDown | C6A1 | LD A,(IX+$04) | Load A with the current entity's room index. | |
| C6A4 | CP $01 | Is the current entity's room index equal to 01? If so, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C6A6 | JR Z,Update_Task_Three_Helpers_AdvanceSlot | |||
| C6A8 | DEC (IX+$05) | Move this entity one character up. | ||
| C6AB | DEC (IX+$06) | |||
| C6AE | DEC (IX+$04) | Move this entity back one room. | ||
| C6B1 | JR Update_Task_Three_Helpers_AdvanceSlot | Jump to Update_Task_Three_Helpers_AdvanceSlot to advance to the next helper entity. | ||
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Try a left wander step, respecting the high-X and low-X bounds.
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| Update_Task_Three_Helpers_TryMoveLeft | C6B3 | LD A,(IX+$07) | Load A with the current entity's x-coordinate. | |
| C6B6 | CP $E0 | Is the current entity's x-coordinate less than E0? If so, jump to Update_Task_Three_Helpers_LeftBoundCheck. | ||
| C6B8 | JR C,Update_Task_Three_Helpers_LeftBoundCheck | |||
| C6BA | CP $E4 | Is the current entity's x-coordinate less than E4? If so, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C6BC | JR C,Update_Task_Three_Helpers_AdvanceSlot | |||
| C6BE | JR Update_Task_Three_Helpers_DecX | Jump to Update_Task_Three_Helpers_DecX to decrease the helper's x-coordinate. | ||
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Left-bound check: below 43 step right instead of left.
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| Update_Task_Three_Helpers_LeftBoundCheck | C6C0 | CP $43 | Is the current entity's x-coordinate less than 43? If so, jump to Update_Task_Three_Helpers_IncX. | |
| C6C2 | JR C,Update_Task_Three_Helpers_IncX | |||
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Nudge the helper one character left.
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| Update_Task_Three_Helpers_DecX | C6C4 | DEC (IX+$07) | Move this entity one character left. | |
| C6C7 | DEC (IX+$08) | |||
| C6CA | JR Update_Task_Three_Helpers_AdvanceSlot | Jump to Update_Task_Three_Helpers_AdvanceSlot to advance to the next helper entity. | ||
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Try a right wander step, respecting the high-X and mid-X bounds.
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| Update_Task_Three_Helpers_TryMoveRight | C6CC | LD A,(IX+$07) | Load A with the current entity's x-coordinate. | |
| C6CF | CP $E0 | Is the current entity's x-coordinate less than E0? If so, jump to Update_Task_Three_Helpers_RightBoundCheck. | ||
| C6D1 | JR C,Update_Task_Three_Helpers_RightBoundCheck | |||
| C6D3 | CP $FB | Is the current entity's x-coordinate less than FB? If not, jump to Update_Task_Three_Helpers_AdvanceSlot. | ||
| C6D5 | JR NC,Update_Task_Three_Helpers_AdvanceSlot | |||
| C6D7 | JR Update_Task_Three_Helpers_IncX | Jump to Update_Task_Three_Helpers_IncX to increase the helper's x-coordinate. | ||
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Right-bound check: at or beyond BB step left instead of right.
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| Update_Task_Three_Helpers_RightBoundCheck | C6D9 | CP $BB | Is the current entity's x-coordinate less than BB? If not, jump to Update_Task_Three_Helpers_DecX. | |
| C6DB | JR NC,Update_Task_Three_Helpers_DecX | |||
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Nudge the helper one character right.
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| Update_Task_Three_Helpers_IncX | C6DD | INC (IX+$07) | Move this entity one character right. | |
| C6E0 | INC (IX+$08) | |||
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Advance to the next helper slot and loop until all 04 are done.
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| Update_Task_Three_Helpers_AdvanceSlot | C6E3 | ADD IX,DE | Advance IX to the next entity record. | |
| C6E5 | POP BC | Restore BC from the stack. | ||
| C6E6 | DEC B | Step the loop counter in B back by one. | ||
| C6E7 | JP NZ,Update_Task_Three_Helpers_Scan | If the result was non-zero, jump to Update_Task_Three_Helpers_Scan. | ||
| C6EA | RET | Return. | ||
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Clear type bit 07 (end the 'loose' pose) and advance.
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| Update_Task_Three_Helpers_ClearTypeBit7 | C6EB | RES 7,(IX+$00) | Reset bit 07 of the current entity's entity type. | |
| C6EF | JR Update_Task_Three_Helpers_AdvanceSlot | Jump to Update_Task_Three_Helpers_AdvanceSlot to advance to the next helper entity. | ||
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When X is below E0, clear type bit 07 and raise SlimyLoose on TaskThreeFlags.
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| Update_Task_Three_Helpers_MaybeSetFlagBit2 | C6F1 | LD A,(IX+$07) | Load A with the current entity's x-coordinate. | |
| C6F4 | CP $E0 | Is the current entity's x-coordinate less than E0? If not, jump to Update_Task_Three_Helpers_MaybeSetTypeBit7. | ||
| C6F6 | JR NC,Update_Task_Three_Helpers_MaybeSetTypeBit7 | |||
| C6F8 | RES 7,(IX+$00) | Reset bit 07 of the current entity's entity type. | ||
| C6FC | LD HL,$72B6 | Point HL at the task-three flags (TaskThreeFlags). | ||
| C6FF | SET 2,(HL) | Set SlimyLoose (bit 02 of TaskThreeFlags. D907 skips that line while set). | ||
| C701 | RET | Return. | ||
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Rarely set type bit 07 so this helper can enter the SlimyLoose path.
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| Update_Task_Three_Helpers_MaybeSetTypeBit7 | C702 | LD A,$0A | Load A with 0A. | |
| C704 | CALL PseudoRandom | Call PseudoRandom to pick a pseudo-random value. | ||
| C707 | OR A | Is the random result in A zero? If not, return. | ||
| C708 | RET NZ | |||
| C709 | SET 7,(IX+$00) | Set bit 07 of the current entity's entity type. | ||
| C70D | RET | Return. | ||
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