Routines
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39657: Place Flame
Used by the routine at SpawnFlame.
Chooses a position for a new flame. Depending on bit 0 of the counter at GameTimer the flame is either placed in the same column as the player (with a position from the frame counter for its row, see ChoosePosition_SetY) or in the same row as the player (see PlaceFlame_InRow). It then finishes by checking the position, see ChoosePosition_Test.
Input
IX Flame record
Output
F Carry flag set if the position is unsuitable
PlaceFlame 39657 LD A,(38547) Fetch the low byte of the game timer from GameTimer.
39660 AND %00000001 Keep only bit 0.
39662 JR NZ,PlaceFlame_InRow Jump to PlaceFlame_InRow if the flame is to appear in the same row as the player.
Use the same X position as the player.
39664 LD A,(38661) Fetch the X position of the player from 38661.
39667 LD (IX+3),A Set the X position of the flame.
39670 LD E,A Copy the X position to E.
39671 JR ChoosePosition_SetY Jump to ChoosePosition_SetY to choose the Y position.
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