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Routines |
| Prev: 44358 | Up: Map | Next: 44478 |
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Sets up the drawing of the new sprite of an object. Finds the sprite from its type and state, and its position on the screen (which frees the slot if it is off screen). If the object is exploding (bit 3 of offset 23), the explosion count in the bottom three bits is increased and the slot is freed when it reaches eight; the count is also used as the dissolve step in 41730. The attribute of the sprite is taken from offset 13, which holds two colours; the choice between them depends on bit 0 of the frame counter at FrameCounter.
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| PrepareDraw | 44360 | LD (44358),IX | Update the current object. | |||||
| 44364 | XOR A | Clear A. | ||||||
| 44365 | LD (41730),A | No dissolve yet. | ||||||
| 44368 | CALL FetchFrameSprite | Call FetchFrameSprite. | ||||||
| 44371 | PUSH DE | Stash DE on the stack. | ||||||
| 44372 | CALL FindObjectScreenPosition | Call FindObjectScreenPosition. | ||||||
| 44375 | POP DE | Bring DE back off the stack. | ||||||
| 44376 | BIT 3,(IX+23) | Jump to PrepareDraw_Colour if bit 3 of offset 23 of IX is clear. | ||||||
| 44380 | JR Z,PrepareDraw_Colour | |||||||
| 44382 | LD A,(IX+23) | The second set of flags. | ||||||
| 44385 | AND %00000111 | Keep the bits of A that are set in 7. | ||||||
| 44387 | INC A | Advance A. | ||||||
| 44388 | LD B,A | B=A. | ||||||
| 44389 | CP 8 | Jump to PrepareDraw_Attributes if A is not 8. | ||||||
| 44391 | JR NZ,PrepareDraw_Attributes | |||||||
| 44393 | LD (IX+0),255 | Store 255 at offset 0 of IX. | ||||||
| 44397 | RES 7,(IX+16) | Reset bit 7 of offset 16 of IX. | ||||||
| 44401 | JR PrepareDraw_Colour | Jump to PrepareDraw_Colour. | ||||||
| PrepareDraw_Attributes | 44403 | LD A,(IX+23) | The second set of flags. | |||||
| 44406 | AND %11110000 | Keep the bits of A that are set in 240. | ||||||
| 44408 | OR B | Set the bits of A that are set in B. | ||||||
| 44409 | OR %00001000 | Set the bits of A that are set in 8. | ||||||
| 44411 | LD (IX+23),A | Write the second set of flags. | ||||||
| 44414 | LD A,B | A=B. | ||||||
| 44415 | OR %10000000 | Set the bits of A that are set in 128. | ||||||
| 44417 | LD (41730),A | The dissolve step of the explosion. | ||||||
| PrepareDraw_Colour | 44420 | LD A,(IX+16) | The flags. | |||||
| 44423 | LD (23601),A | Update the contact flags. | ||||||
| 44426 | BIT 7,A | Return if bit 7 of A is clear. | ||||||
| 44428 | RET Z | |||||||
| 44429 | LD C,(IX+13) | The attribute. | ||||||
| 44432 | LD A,(39524) | The frame counter. | ||||||
| 44435 | AND %00000001 | Keep the bits of A that are set in 1. | ||||||
| 44437 | JR Z,PrepareDraw_Colour2 | Jump to PrepareDraw_Colour2 if the zero flag is set. | ||||||
| 44439 | LD A,C | A=C. | ||||||
| 44440 | AND %00001000 | Keep the bits of A that are set in 8. | ||||||
| 44442 | ADD A,A | Double A. | ||||||
| 44443 | ADD A,A | Double A. | ||||||
| 44444 | ADD A,A | Double A. | ||||||
| 44445 | LD B,A | B=A. | ||||||
| 44446 | LD A,C | A=C. | ||||||
| 44447 | AND %00000111 | Keep the bits of A that are set in 7. | ||||||
| 44449 | JR PrepareDraw_Attribute | Jump to PrepareDraw_Attribute. | ||||||
| PrepareDraw_Colour2 | 44451 | LD A,C | A=C. | |||||
| 44452 | AND %01110000 | Keep the bits of A that are set in 112. | ||||||
| 44454 | SRL A | Shift A right. | ||||||
| 44456 | SRL A | Shift A right. | ||||||
| 44458 | SRL A | Shift A right. | ||||||
| 44460 | SRL A | Shift A right. | ||||||
| 44462 | LD B,A | B=A. | ||||||
| 44463 | LD A,C | A=C. | ||||||
| 44464 | AND %10000000 | Keep the bits of A that are set in 128. | ||||||
| 44466 | SRL A | Shift A right. | ||||||
| PrepareDraw_Attribute | 44468 | OR B | Set the bits of A that are set in B. | |||||
| 44469 | LD (44803),A | The attribute of the sprite. | ||||||
| 44472 | CALL ClipSecondSprite | Call ClipSecondSprite. | ||||||
| 44475 | JP SelectDrawSprite | Jump to SelectDrawSprite. | ||||||
| Prev: 44358 | Up: Map | Next: 44478 |