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Routines |
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The handler of DrawGraphic for a graphic that is flipped top to bottom. This is the same as DrawGraphic_Upright, except that it starts from the last row and works up using SubtractWidthFromAddress.
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| DrawGraphic_Flipped | 9ACB | POP BC | Restore the attribute and graphic ID from the stack. | |
| 9ACC | CALL GetBlendInstruction | Call GetBlendInstruction to get the instruction to mix the graphic with the screen. | ||
| 9ACF | LD ($9ADD),A | Write it over the instruction at 9ADD. | ||
| 9AD2 | CALL GetGraphicDetails | Call GetGraphicDetails to get the details of the graphic. | ||
| 9AD5 | CALL FindLastRow | Call FindLastRow to move on to the last row. | ||
| DrawGraphic_Flipped_Row | 9AD8 | PUSH BC | Stash the width and height on the stack. | |
| 9AD9 | PUSH DE | Stash the position in the graphic on the stack. | ||
| 9ADA | PUSH HL | Stash the screen address on the stack. | ||
| DrawGraphic_Flipped_Byte | 9ADB | LD A,(DE) | Fetch the next byte of the graphic. | |
| 9ADC | INC DE | Move DE on to the next byte. | ||
| 9ADD | NOP | This is replaced by an instruction that mixes A with the screen. | ||
| 9ADE | LD (HL),A | Write A to the screen. | ||
| 9ADF | INC L | Move HL on to the next byte. | ||
| 9AE0 | DJNZ DrawGraphic_Flipped_Byte | Decrease the width by one and loop back to DrawGraphic_Flipped_Byte until all of the bytes in the row have been drawn. | ||
| 9AE2 | POP HL | Restore the screen address from the stack. | ||
| 9AE3 | CALL ScreenPosition1PixelAbove | Call ScreenPosition1PixelAbove to move up a line. | ||
| 9AE6 | POP DE | Restore the position in the graphic from the stack. | ||
| 9AE7 | POP BC | Restore the width and height from the stack. | ||
| 9AE8 | CALL SubtractWidthFromAddress | Call SubtractWidthFromAddress to move back to the previous row of the graphic. | ||
| 9AEB | DEC C | Decrease the height by one and loop back to DrawGraphic_Flipped_Row until all of the rows have been done. | ||
| 9AEC | JR NZ,DrawGraphic_Flipped_Row | |||
| 9AEE | RET | Return. | ||
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