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Routines |
| Prev: 44504 | Up: Map | Next: 44801 |
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Works out the area of attribute cells that is covered by the sprite that has just been drawn, as a width and height in cells, and fills it with the attribute at 44803 by calling FillAttributes.
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| SetObjectAttributes | 44696 | LD A,(41432) | The rows of the sprite. | |
| 44699 | DEC A | Step A back. | ||
| 44700 | RET M | Return if the sign flag is set. | ||
| 44701 | LD D,A | D=A. | ||
| 44702 | LD HL,(41429) | Fetch the word at 41429 into HL. | ||
| 44705 | LD A,(23593) | The width of the sprite in bytes. | ||
| 44708 | LD B,A | B=A. | ||
| 44709 | LD A,(41722) | The sprite reaches past the right of the screen. | ||
| 44712 | AND A | Jump to SetObjectAttributes_Width if A is zero. | ||
| 44713 | JR Z,SetObjectAttributes_Width | |||
| 44715 | LD A,L | A=L. | ||
| 44716 | ADD A,B | A gains B. | ||
| 44717 | SUB 164 | Subtract 164 from A. | ||
| 44719 | LD L,8 | L=8. | ||
| 44721 | JR SetObjectAttributes_Cells | Jump to SetObjectAttributes_Cells. | ||
| SetObjectAttributes_Width | 44723 | LD A,L | A=L. | |
| 44724 | CP 8 | Jump to SetObjectAttributes_Right if A is 8 or more. | ||
| 44726 | JR NC,SetObjectAttributes_Right | |||
| 44728 | ADD A,8 | Add 8 to A. | ||
| 44730 | LD L,A | L=A. | ||
| 44731 | LD A,B | A=B. | ||
| 44732 | SUB 8 | Subtract 8 from A. | ||
| 44734 | LD B,A | B=A. | ||
| SetObjectAttributes_Right | 44735 | LD A,L | A=L. | |
| 44736 | ADD A,23 | Add 23 to A. | ||
| 44738 | ADD A,B | A gains B. | ||
| 44739 | JR NC,SetObjectAttributes_Aligned | Jump to SetObjectAttributes_Aligned if the carry flag is clear. | ||
| 44741 | LD A,238 | A=238. | ||
| 44743 | SUB L | Subtract L from A. | ||
| 44744 | JR SetObjectAttributes_Cells | Jump to SetObjectAttributes_Cells. | ||
| SetObjectAttributes_Aligned | 44746 | LD A,L | A=L. | |
| 44747 | AND %00000111 | Keep the bits of A that are set in 7. | ||
| 44749 | JR Z,SetObjectAttributes_Sum | Jump to SetObjectAttributes_Sum if the zero flag is set. | ||
| 44751 | LD A,B | A=B. | ||
| 44752 | ADD A,8 | Add 8 to A. | ||
| 44754 | LD B,A | B=A. | ||
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This entry point is used by the routine at DrawShot.
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| SetObjectAttributes_Sum | 44755 | LD A,L | A=L. | |
| 44756 | ADD A,B | A gains B. | ||
| 44757 | SUB L | Subtract L from A. | ||
| SetObjectAttributes_Cells | 44758 | SRL A | Shift A right. | |
| 44760 | SRL A | Shift A right. | ||
| 44762 | SRL A | Shift A right. | ||
| 44764 | LD (44801),A | Update the attribute area. | ||
| 44767 | DEC A | Step A back. | ||
| 44768 | RET M | Return if the sign flag is set. | ||
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This entry point is used by the routine at SetPairAttributes.
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| SetObjectAttributes_Height | 44769 | LD A,H | A=H. | |
| 44770 | SUB D | Subtract D from A. | ||
| 44771 | SUB 7 | Subtract 7 from A. | ||
| 44773 | LD E,A | E=A. | ||
| 44774 | CP 23 | Jump to SetObjectAttributes_Rows if A is 23 or more. | ||
| 44776 | JR NC,SetObjectAttributes_Rows | |||
| 44778 | LD E,23 | E=23. | ||
| SetObjectAttributes_Rows | 44780 | LD A,H | A=H. | |
| 44781 | OR %00000111 | Set the bits of A that are set in 7. | ||
| 44783 | SUB E | Subtract E from A. | ||
| 44784 | SRL A | Shift A right. | ||
| 44786 | SRL A | Shift A right. | ||
| 44788 | SRL A | Shift A right. | ||
| 44790 | LD (44802),A | The height of the attribute area. | ||
| 44793 | DEC A | Step A back. | ||
| 44794 | RET M | Return if the sign flag is set. | ||
| 44795 | LD DE,44801 | The attribute area. | ||
| 44798 | JP FillAttributes | Jump to FillAttributes. | ||
| Prev: 44504 | Up: Map | Next: 44801 |